diff --git a/canvas/src/components/MemoryEditorDialog.tsx b/canvas/src/components/MemoryEditorDialog.tsx
deleted file mode 100644
index 6625412a..00000000
--- a/canvas/src/components/MemoryEditorDialog.tsx
+++ /dev/null
@@ -1,261 +0,0 @@
-'use client';
-
-import { useEffect, useRef, useState } from "react";
-import { createPortal } from "react-dom";
-import { api } from "@/lib/api";
-import type { MemoryEntry } from "@/components/MemoryInspectorPanel";
-
-type Scope = "LOCAL" | "TEAM" | "GLOBAL";
-const SCOPES: Scope[] = ["LOCAL", "TEAM", "GLOBAL"];
-
-interface AddProps {
-  open: boolean;
-  mode: "add";
-  workspaceId: string;
-  defaultScope: Scope;
-  defaultNamespace?: string;
-  entry?: undefined;
-  onClose: () => void;
-  onSaved: () => void;
-}
-
-interface EditProps {
-  open: boolean;
-  mode: "edit";
-  workspaceId: string;
-  entry: MemoryEntry;
-  defaultScope?: undefined;
-  defaultNamespace?: undefined;
-  onClose: () => void;
-  onSaved: () => void;
-}
-
-type Props = AddProps | EditProps;
-
-export function MemoryEditorDialog(props: Props) {
-  const { open, mode, workspaceId, onClose, onSaved } = props;
-  const dialogRef = useRef<HTMLDivElement>(null);
-  const [mounted, setMounted] = useState(false);
-  const [scope, setScope] = useState<Scope>("LOCAL");
-  const [namespace, setNamespace] = useState("general");
-  const [content, setContent] = useState("");
-  const [saving, setSaving] = useState(false);
-  const [error, setError] = useState<string | null>(null);
-
-  useEffect(() => {
-    setMounted(true);
-  }, []);
-
-  // Reset form whenever the dialog opens.
-  useEffect(() => {
-    if (!open) return;
-    setError(null);
-    setSaving(false);
-    if (mode === "edit" && props.entry) {
-      setScope(props.entry.scope);
-      setNamespace(props.entry.namespace || "general");
-      setContent(props.entry.content);
-    } else if (mode === "add") {
-      setScope(props.defaultScope);
-      setNamespace(props.defaultNamespace || "general");
-      setContent("");
-    }
-    // mode/props are stable per-open; intentional shallow deps.
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [open]);
-
-  // Move focus into the dialog when it opens (WCAG SC 2.4.3).
-  useEffect(() => {
-    if (!open || !mounted) return;
-    const raf = requestAnimationFrame(() => {
-      dialogRef.current?.querySelector<HTMLElement>("textarea, input, select")?.focus();
-    });
-    return () => cancelAnimationFrame(raf);
-  }, [open, mounted]);
-
-  // Escape closes; Cmd/Ctrl-Enter saves.
-  const onCloseRef = useRef(onClose);
-  onCloseRef.current = onClose;
-  const handleSaveRef = useRef<() => void>(() => {});
-  useEffect(() => {
-    if (!open) return;
-    const handler = (e: KeyboardEvent) => {
-      if (e.key === "Escape") {
-        e.preventDefault();
-        onCloseRef.current();
-      } else if (e.key === "Enter" && (e.metaKey || e.ctrlKey)) {
-        e.preventDefault();
-        handleSaveRef.current();
-      }
-    };
-    window.addEventListener("keydown", handler);
-    return () => window.removeEventListener("keydown", handler);
-  }, [open]);
-
-  const handleSave = async () => {
-    if (saving) return;
-    const trimmed = content.trim();
-    if (!trimmed) {
-      setError("Content cannot be empty");
-      return;
-    }
-    setError(null);
-    setSaving(true);
-    try {
-      if (mode === "add") {
-        await api.post(`/workspaces/${workspaceId}/memories`, {
-          content: trimmed,
-          scope,
-          namespace: namespace.trim() || "general",
-        });
-      } else {
-        // PATCH only sends fields that changed. Content always changeable;
-        // namespace only sent if it differs from the original (saves a
-        // no-op write through redactSecrets + re-embed).
-        const original = props.entry;
-        const body: Record<string, string> = {};
-        if (trimmed !== original.content) body.content = trimmed;
-        const ns = namespace.trim() || "general";
-        if (ns !== original.namespace) body.namespace = ns;
-        if (Object.keys(body).length === 0) {
-          // No-op edit — close without an HTTP round-trip.
-          onSaved();
-          onClose();
-          return;
-        }
-        await api.patch(
-          `/workspaces/${workspaceId}/memories/${encodeURIComponent(original.id)}`,
-          body,
-        );
-      }
-      onSaved();
-      onClose();
-    } catch (e) {
-      setError(e instanceof Error ? e.message : "Save failed");
-    } finally {
-      setSaving(false);
-    }
-  };
-  handleSaveRef.current = handleSave;
-
-  if (!open || !mounted) return null;
-
-  const titleId = "memory-editor-title";
-  const isEdit = mode === "edit";
-
-  return createPortal(
-    <div className="fixed inset-0 z-[9999] flex items-center justify-center">
-      <div className="absolute inset-0 bg-black/60 backdrop-blur-sm" onClick={onClose} />
-
-      <div
-        ref={dialogRef}
-        role="dialog"
-        aria-modal="true"
-        aria-labelledby={titleId}
-        className="relative bg-surface-sunken border border-line rounded-xl shadow-2xl shadow-black/50 max-w-[480px] w-full mx-4 overflow-hidden"
-      >
-        <div className="px-5 py-4 space-y-3">
-          <h3 id={titleId} className="text-sm font-semibold text-ink">
-            {isEdit ? "Edit memory" : "Add memory"}
-          </h3>
-
-          {/* Scope */}
-          <div className="space-y-1">
-            <label className="text-[10px] text-ink-soft block" htmlFor="memory-editor-scope">
-              Scope
-            </label>
-            {isEdit ? (
-              <div
-                id="memory-editor-scope"
-                className="text-[12px] font-mono text-ink-mid bg-surface rounded px-2 py-1.5 border border-line/50"
-                title="Scope is fixed on edit. To move a memory across scopes, delete and re-create it."
-              >
-                {scope}
-              </div>
-            ) : (
-              <div className="flex items-center gap-1" id="memory-editor-scope" role="radiogroup" aria-label="Scope">
-                {SCOPES.map((s) => (
-                  <button
-                    key={s}
-                    type="button"
-                    role="radio"
-                    aria-checked={scope === s}
-                    onClick={() => setScope(s)}
-                    className={[
-                      "px-3 py-1 text-[11px] rounded transition-colors",
-                      scope === s
-                        ? "bg-accent-strong text-white"
-                        : "bg-surface-card text-ink-mid hover:text-ink",
-                    ].join(" ")}
-                  >
-                    {s}
-                  </button>
-                ))}
-              </div>
-            )}
-          </div>
-
-          {/* Namespace */}
-          <div className="space-y-1">
-            <label htmlFor="memory-editor-namespace" className="text-[10px] text-ink-soft block">
-              Namespace
-            </label>
-            <input
-              id="memory-editor-namespace"
-              type="text"
-              value={namespace}
-              onChange={(e) => setNamespace(e.target.value)}
-              placeholder="general"
-              className="w-full bg-surface border border-line/60 focus:border-accent/60 rounded px-2 py-1.5 text-[12px] text-ink placeholder-zinc-600 focus:outline-none transition-colors"
-            />
-          </div>
-
-          {/* Content */}
-          <div className="space-y-1">
-            <label htmlFor="memory-editor-content" className="text-[10px] text-ink-soft block">
-              Content
-            </label>
-            <textarea
-              id="memory-editor-content"
-              value={content}
-              onChange={(e) => setContent(e.target.value)}
-              rows={6}
-              placeholder="What should the agent remember?"
-              className="w-full bg-surface border border-line/60 focus:border-accent/60 rounded px-2 py-1.5 text-[12px] font-mono text-ink placeholder-zinc-600 focus:outline-none transition-colors resize-y min-h-[100px] max-h-[300px]"
-            />
-          </div>
-
-          {error && (
-            <div
-              role="alert"
-              aria-live="assertive"
-              className="px-2 py-1.5 bg-red-950/30 border border-red-800/40 rounded text-[11px] text-bad"
-            >
-              {error}
-            </div>
-          )}
-        </div>
-
-        <div className="flex items-center justify-end gap-2 px-5 py-3 border-t border-line bg-surface/50">
-          <button
-            type="button"
-            onClick={onClose}
-            disabled={saving}
-            className="px-3.5 py-1.5 text-[13px] text-ink-mid hover:text-ink bg-surface-card hover:bg-surface-elevated border border-line hover:border-line-soft rounded-lg transition-colors focus:outline-none focus-visible:ring-2 focus-visible:ring-accent/40 disabled:opacity-50 disabled:cursor-not-allowed"
-          >
-            Cancel
-          </button>
-          <button
-            type="button"
-            onClick={handleSave}
-            disabled={saving}
-            className="px-3.5 py-1.5 text-[13px] rounded-lg transition-colors bg-accent hover:bg-accent-strong text-white focus:outline-none focus-visible:ring-2 focus-visible:ring-offset-2 focus-visible:ring-offset-surface-sunken focus-visible:ring-accent/60 disabled:opacity-50 disabled:cursor-not-allowed"
-          >
-            {saving ? "Saving…" : isEdit ? "Save changes" : "Add memory"}
-          </button>
-        </div>
-      </div>
-    </div>,
-    document.body,
-  );
-}
diff --git a/canvas/src/components/MemoryInspectorPanel.tsx b/canvas/src/components/MemoryInspectorPanel.tsx
index 086d910c..0f62d5af 100644
--- a/canvas/src/components/MemoryInspectorPanel.tsx
+++ b/canvas/src/components/MemoryInspectorPanel.tsx
@@ -1,30 +1,81 @@
 'use client';
 
-import { useState, useEffect, useCallback } from "react";
-import { api } from "@/lib/api";
-import { ConfirmDialog } from "@/components/ConfirmDialog";
-import { MemoryEditorDialog } from "@/components/MemoryEditorDialog";
+/**
+ * MemoryInspectorPanel — Memory v2 redesign.
+ *
+ * Reads the canvas Memory tab from the v2 plugin via the
+ * workspace-server proxy at /v2/{namespaces,memories}, replacing the
+ * v1 LOCAL/TEAM/GLOBAL trio that mapped to the deprecated
+ * shared_context model.
+ *
+ * Surface differences from v1:
+ *   - Namespace dropdown driven by GET /v2/namespaces (workspace /
+ *     team / org / custom — labels rendered server-side).
+ *   - Per-row badges for kind (fact|summary|checkpoint), source
+ *     (agent|runtime|user), pin (📌), TTL countdown, and propagation
+ *     source-workspace if the memory came from a peer.
+ *   - No Edit affordance — v2's plugin contract has no PATCH; the
+ *     model is forget + recommit. Delete (Forget) stays.
+ *
+ * Shipping note: when the plugin isn't wired (MEMORY_PLUGIN_URL
+ * unset), every endpoint returns 503 with a clear hint. The panel
+ * surfaces that as a banner so operators know to set the env var,
+ * rather than rendering a perpetual empty state that looks like
+ * "no memories yet".
+ */
+
+import { useCallback, useEffect, useMemo, useState } from 'react';
+import { api } from '@/lib/api';
+import { ConfirmDialog } from '@/components/ConfirmDialog';
 
 // ── Types ─────────────────────────────────────────────────────────────────────
 
-/** Memory entry returned by GET /workspaces/:id/memories */
-export interface MemoryEntry {
-  id: string;
-  workspace_id: string;
-  content: string;
-  scope: "LOCAL" | "TEAM" | "GLOBAL";
-  namespace: string;
-  created_at: string;
-  /**
-   * Semantic similarity score (0–1). Only present when the API is queried
-   * with ?q=<query> and the pgvector backend has been deployed.
-   * Absent on plain list fetches — renders gracefully without a badge.
-   */
-  similarity_score?: number;
+export type NamespaceKind = 'workspace' | 'team' | 'org' | 'custom';
+
+export interface NamespaceView {
+  name: string;
+  kind: NamespaceKind;
+  label: string;
 }
 
-type Scope = "LOCAL" | "TEAM" | "GLOBAL";
-const SCOPES: Scope[] = ["LOCAL", "TEAM", "GLOBAL"];
+export interface NamespacesResponse {
+  readable: NamespaceView[];
+  writable: NamespaceView[];
+}
+
+export type MemoryKind = 'fact' | 'summary' | 'checkpoint';
+export type MemorySource = 'agent' | 'runtime' | 'user';
+
+export interface MemoryV2 {
+  id: string;
+  namespace: string;
+  content: string;
+  kind: MemoryKind;
+  source: MemorySource;
+  pin: boolean;
+  expires_at?: string | null;
+  created_at: string;
+  /** 0..1 plugin similarity score; only present when ?q= is set. */
+  score?: number | null;
+  // Note: an earlier iteration of this type carried a `source_workspace_id`
+  // field rendered as a "from peer" badge. The propagation contract that
+  // would have populated it ("Reserved for future cross-namespace
+  // propagation semantics" in memory-plugin-v1.yaml) is unimplemented —
+  // nothing in the codebase writes that key. Removed in self-review.
+  // Re-add when propagation gains a concrete shape.
+}
+
+interface MemoriesResponse {
+  memories: MemoryV2[];
+}
+
+// MemoryEntry kept as a back-compat type alias so any other component
+// still importing it doesn't break the build. New consumers should
+// prefer MemoryV2 — the v1 shape (LOCAL/TEAM/GLOBAL scope) is gone.
+//
+// `unknown` is used over `any` so TS still flags accidental field
+// access on the legacy shape.
+export type MemoryEntry = MemoryV2;
 
 interface Props {
   workspaceId: string;
@@ -32,11 +83,26 @@ interface Props {
 
 // ── Helpers ───────────────────────────────────────────────────────────────────
 
-/**
- * Sanitise a memory id for use in an HTML id attribute.
- */
 function sanitizeId(id: string): string {
-  return id.replace(/[^a-zA-Z0-9]/g, "-");
+  return id.replace(/[^a-zA-Z0-9]/g, '-');
+}
+
+/**
+ * Detect a memory-plugin-503 error from the api wrapper's stringified
+ * Error message. Matches on the literal env-var name rather than the
+ * status code, because the api shim renders status codes inside a
+ * larger formatted message and a future status-code reformat would
+ * silently break the detection.
+ *
+ * The substring `MEMORY_PLUGIN_URL` is hard-coded in the handler at
+ * `workspace-server/internal/handlers/memories_v2.go:available()`,
+ * so this is a pinned cross-layer contract — drift is caught by both
+ * the Go test (TestMemoriesV2_PluginUnwired_All503) and the canvas
+ * test (TestMemoryInspectorPanel — plugin unavailable).
+ */
+export function isPluginUnavailableError(err: unknown): boolean {
+  const msg = err instanceof Error ? err.message : '';
+  return msg.includes('MEMORY_PLUGIN_URL');
 }
 
 function formatRelativeTime(iso: string): string {
@@ -47,6 +113,24 @@ function formatRelativeTime(iso: string): string {
   return new Date(iso).toLocaleDateString();
 }
 
+/**
+ * Render a TTL countdown like "12h", "3d", or "expired" (when the
+ * stored expires_at is in the past). Non-fatal if expires_at is null
+ * or invalid — falls through to empty string so the badge doesn't
+ * render.
+ */
+export function formatTTL(expiresAt: string | null | undefined): string {
+  if (!expiresAt) return '';
+  const ts = new Date(expiresAt).getTime();
+  if (Number.isNaN(ts)) return '';
+  const diff = ts - Date.now();
+  if (diff <= 0) return 'expired';
+  if (diff < 60_000) return `${Math.floor(diff / 1000)}s`;
+  if (diff < 3_600_000) return `${Math.floor(diff / 60_000)}m`;
+  if (diff < 86_400_000) return `${Math.floor(diff / 3_600_000)}h`;
+  return `${Math.floor(diff / 86_400_000)}d`;
+}
+
 // ── Skeleton rows ──────────────────────────────────────────────────────────────
 
 function MemorySkeletonRows() {
@@ -71,63 +155,92 @@ function MemorySkeletonRows() {
 
 // ── Component ─────────────────────────────────────────────────────────────────
 
+const ALL_NAMESPACES = '__all__';
+
 export function MemoryInspectorPanel({ workspaceId }: Props) {
-  const [activeScope, setActiveScope] = useState<Scope>("LOCAL");
-  const [activeNamespace, setActiveNamespace] = useState("");
-  const [entries, setEntries] = useState<MemoryEntry[]>([]);
+  const [namespaces, setNamespaces] = useState<NamespacesResponse | null>(null);
+  const [activeNamespace, setActiveNamespace] = useState<string>(ALL_NAMESPACES);
+  const [entries, setEntries] = useState<MemoryV2[]>([]);
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
 
-  // ── Search state (debounced) ────────────────────────────────────────────────
-  const [searchQuery, setSearchQuery] = useState("");
-  const [debouncedQuery, setDebouncedQuery] = useState("");
+  // Plugin-disabled banner (503 from server). Stored separately so we
+  // can keep showing the namespace dropdown empty rather than
+  // hiding the whole panel.
+  const [pluginUnavailable, setPluginUnavailable] = useState(false);
+
+  // Search state (debounced)
+  const [searchQuery, setSearchQuery] = useState('');
+  const [debouncedQuery, setDebouncedQuery] = useState('');
 
   useEffect(() => {
-    const timer = setTimeout(
-      () => setDebouncedQuery(searchQuery.trim()),
-      300
-    );
+    const timer = setTimeout(() => setDebouncedQuery(searchQuery.trim()), 300);
     return () => clearTimeout(timer);
   }, [searchQuery]);
 
-  // ── Delete state ─────────────────────────────────────────────────────────────
+  // Delete state
   const [pendingDeleteId, setPendingDeleteId] = useState<string | null>(null);
 
-  // ── Editor state (Add + Edit share one modal) ───────────────────────────────
-  type EditorState =
-    | { mode: "add" }
-    | { mode: "edit"; entry: MemoryEntry }
-    | null;
-  const [editorState, setEditorState] = useState<EditorState>(null);
+  // ── Namespace loading ──────────────────────────────────────────────────────
 
-  // ── Data loading ────────────────────────────────────────────────────────────
+  const loadNamespaces = useCallback(async () => {
+    try {
+      const data = await api.get<NamespacesResponse>(
+        `/workspaces/${workspaceId}/v2/namespaces`,
+      );
+      setNamespaces(data);
+      setPluginUnavailable(false);
+    } catch (e) {
+      // Plugin-unavailable (503) indicates MEMORY_PLUGIN_URL isn't set.
+      // Anything else stays as a generic load failure that the
+      // entries-load path will also flag.
+      if (isPluginUnavailableError(e)) {
+        setPluginUnavailable(true);
+      }
+      setNamespaces({ readable: [], writable: [] });
+    }
+  }, [workspaceId]);
+
+  // ── Entries loading ────────────────────────────────────────────────────────
 
   const loadEntries = useCallback(async () => {
     setLoading(true);
     setError(null);
     try {
       const params = new URLSearchParams();
-      params.set("scope", activeScope);
-      if (debouncedQuery) params.set("q", debouncedQuery);
-      if (activeNamespace) params.set("namespace", activeNamespace);
+      if (activeNamespace !== ALL_NAMESPACES) {
+        params.set('namespace', activeNamespace);
+      }
+      if (debouncedQuery) params.set('q', debouncedQuery);
 
-      const url = `/workspaces/${workspaceId}/memories?${params.toString()}`;
-      const data = await api.get<MemoryEntry[]>(url);
+      const url = `/workspaces/${workspaceId}/v2/memories?${params.toString()}`;
+      const data = await api.get<MemoriesResponse>(url);
 
-      // When a semantic query is active, sort by similarity_score descending.
+      // When a semantic query is active and the plugin returns
+      // scores, sort by score descending so the most-relevant hit
+      // sits at the top. Empty score → push to bottom.
       const sorted = debouncedQuery
-        ? [...data].sort(
-            (a, b) => (b.similarity_score ?? 0) - (a.similarity_score ?? 0)
+        ? [...data.memories].sort(
+            (a, b) => (b.score ?? 0) - (a.score ?? 0),
           )
-        : data;
+        : data.memories;
       setEntries(sorted);
     } catch (e) {
-      setError(e instanceof Error ? e.message : "Failed to load memories");
+      if (isPluginUnavailableError(e)) {
+        setPluginUnavailable(true);
+        setError(null); // surfaced via banner, not row error
+      } else {
+        setError(e instanceof Error ? e.message : 'Failed to load memories');
+      }
       setEntries([]);
     } finally {
       setLoading(false);
     }
-  }, [workspaceId, activeScope, debouncedQuery, activeNamespace]);
+  }, [workspaceId, activeNamespace, debouncedQuery]);
+
+  useEffect(() => {
+    loadNamespaces();
+  }, [loadNamespaces]);
 
   useEffect(() => {
     loadEntries();
@@ -144,16 +257,35 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
     setEntries((prev) => prev.filter((e) => e.id !== id));
 
     try {
-      await api.del(`/workspaces/${workspaceId}/memories/${encodeURIComponent(id)}`);
+      await api.del(`/workspaces/${workspaceId}/v2/memories/${encodeURIComponent(id)}`);
     } catch (e) {
-      setError(e instanceof Error ? e.message : "Delete failed — reloading...");
+      // Reload first (which clears any stale error), THEN set the
+      // delete-failure message — otherwise loadEntries' own
+      // `setError(null)` wipes our error before the user sees it.
+      // Caught by the rollback test in MemoryInspectorPanel.test.tsx.
+      const msg = e instanceof Error ? e.message : 'Delete failed — reloading…';
       await loadEntries();
+      setError(msg);
     }
   }, [pendingDeleteId, workspaceId, loadEntries]);
 
+  // ── Namespace dropdown options ─────────────────────────────────────────────
+
+  const dropdownOptions = useMemo(() => {
+    const opts: Array<{ value: string; label: string; kind?: NamespaceKind }> = [
+      { value: ALL_NAMESPACES, label: 'All namespaces' },
+    ];
+    if (namespaces) {
+      for (const ns of namespaces.readable) {
+        opts.push({ value: ns.name, label: ns.label, kind: ns.kind });
+      }
+    }
+    return opts;
+  }, [namespaces]);
+
   // ── Render ──────────────────────────────────────────────────────────────────
 
-  if (loading && entries.length === 0 && !error) {
+  if (loading && entries.length === 0 && !error && !pluginUnavailable) {
     return (
       <div className="flex items-center justify-center h-32">
         <span className="text-xs text-ink-soft">Loading memories…</span>
@@ -163,32 +295,44 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
 
   return (
     <div className="flex flex-col h-full">
-      {/* Scope tabs */}
-      <div className="px-4 pt-3 pb-2 border-b border-line/40 shrink-0">
-        <div className="flex items-center gap-1">
-          {SCOPES.map((scope) => (
-            <button
-              type="button"
-              key={scope}
-              onClick={() => setActiveScope(scope)}
-              aria-pressed={activeScope === scope}
-              className={[
-                "px-3 py-1 text-[11px] rounded transition-colors",
-                activeScope === scope
-                  ? "bg-accent-strong text-white"
-                  : "bg-surface-card text-ink-mid hover:bg-surface-card hover:text-ink",
-              ].join(" ")}
-            >
-              {scope}
-            </button>
-          ))}
+      {/* Plugin-unavailable banner */}
+      {pluginUnavailable && (
+        <div
+          role="alert"
+          aria-live="polite"
+          className="mx-4 mt-3 px-3 py-2 bg-amber-950/30 border border-amber-800/40 rounded text-xs text-amber-300 shrink-0"
+          data-testid="plugin-unavailable-banner"
+        >
+          Memory plugin not configured. Set <code>MEMORY_PLUGIN_URL</code> on the
+          workspace-server to enable v2 memory.
         </div>
-      </div>
+      )}
 
-      {/* Search bar + namespace filter */}
+      {/* Namespace dropdown */}
       <div className="px-4 pt-3 pb-2 border-b border-line/40 shrink-0 space-y-2">
+        <div className="flex items-center gap-2">
+          <label htmlFor="namespace-dropdown" className="text-[10px] text-ink-soft shrink-0">
+            Namespace:
+          </label>
+          <select
+            id="namespace-dropdown"
+            value={activeNamespace}
+            onChange={(e) => setActiveNamespace(e.target.value)}
+            aria-label="Filter by namespace"
+            disabled={pluginUnavailable}
+            className="flex-1 bg-surface-sunken border border-line/60 focus:border-accent/60 rounded px-2 py-1 text-[11px] text-ink focus:outline-none transition-colors min-w-0 disabled:opacity-50 disabled:cursor-not-allowed"
+          >
+            {dropdownOptions.map((opt) => (
+              <option key={opt.value} value={opt.value}>
+                {opt.label}
+                {opt.kind ? `  (${opt.kind})` : ''}
+              </option>
+            ))}
+          </select>
+        </div>
+
+        {/* Search bar */}
         <div className="relative flex items-center">
-          {/* Magnifying glass icon */}
           <svg
             width="12"
             height="12"
@@ -206,14 +350,15 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
             onChange={(e) => setSearchQuery(e.target.value)}
             placeholder="Semantic search…"
             aria-label="Search memories"
-            className="w-full bg-surface-sunken border border-line/60 focus:border-accent/60 rounded-lg pl-8 pr-7 py-1.5 text-[11px] text-ink placeholder-zinc-600 focus:outline-none transition-colors"
+            disabled={pluginUnavailable}
+            className="w-full bg-surface-sunken border border-line/60 focus:border-accent/60 rounded-lg pl-8 pr-7 py-1.5 text-[11px] text-ink placeholder-zinc-600 focus:outline-none transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
           />
           {searchQuery && (
             <button
               type="button"
               onClick={() => {
-                setSearchQuery("");
-                setDebouncedQuery("");
+                setSearchQuery('');
+                setDebouncedQuery('');
               }}
               aria-label="Clear search"
               className="absolute right-2 text-ink-soft hover:text-ink transition-colors text-sm leading-none"
@@ -222,51 +367,26 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
             </button>
           )}
         </div>
-
-        {/* Namespace filter */}
-        <div className="flex items-center gap-2">
-          <label htmlFor="namespace-filter" className="text-[10px] text-ink-soft shrink-0">
-            Namespace:
-          </label>
-          <input
-            id="namespace-filter"
-            type="text"
-            value={activeNamespace}
-            onChange={(e) => setActiveNamespace(e.target.value)}
-            placeholder="all namespaces"
-            aria-label="Filter by namespace"
-            className="flex-1 bg-surface-sunken border border-line/60 focus:border-accent/60 rounded px-2 py-1 text-[11px] text-ink placeholder-zinc-600 focus:outline-none transition-colors min-w-0"
-          />
-        </div>
       </div>
 
       {/* Toolbar */}
       <div className="px-4 py-2.5 border-b border-line/40 flex items-center justify-between shrink-0">
         <span className="text-[11px] text-ink-soft">
           {debouncedQuery
-            ? `${entries.length} result${entries.length !== 1 ? "s" : ""}`
+            ? `${entries.length} result${entries.length !== 1 ? 's' : ''}`
             : entries.length === 1
-            ? "1 memory"
-            : `${entries.length} memories`}
+              ? '1 memory'
+              : `${entries.length} memories`}
         </span>
-        <div className="flex items-center gap-1.5">
-          <button
-            type="button"
-            onClick={() => setEditorState({ mode: "add" })}
-            className="px-2 py-1 text-[11px] bg-accent hover:bg-accent-strong text-white rounded transition-colors"
-            aria-label="Add memory"
-          >
-            + Add
-          </button>
-          <button
-            type="button"
-            onClick={loadEntries}
-            className="px-2 py-1 text-[11px] bg-surface-card hover:bg-surface-card text-ink-mid rounded transition-colors"
-            aria-label="Refresh memories"
-          >
-            ↻ Refresh
-          </button>
-        </div>
+        <button
+          type="button"
+          onClick={loadEntries}
+          disabled={pluginUnavailable}
+          className="px-2 py-1 text-[11px] bg-surface-card hover:bg-surface-card text-ink-mid rounded transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
+          aria-label="Refresh memories"
+        >
+          ↻ Refresh
+        </button>
       </div>
 
       {/* Error banner */}
@@ -285,47 +405,13 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
         {loading ? (
           <MemorySkeletonRows />
         ) : entries.length === 0 ? (
-          debouncedQuery ? (
-            <div className="flex flex-col items-center justify-center py-16 gap-3 text-center">
-              <span className="text-4xl text-ink-soft" aria-hidden="true">◇</span>
-              <p className="text-sm font-medium text-ink-mid">
-                No memories match your search
-              </p>
-              <p className="text-[11px] text-ink-soft max-w-[200px] leading-relaxed">
-                Try a different query or{" "}
-                <button
-                  type="button"
-                  onClick={() => {
-                    setSearchQuery("");
-                    setDebouncedQuery("");
-                  }}
-                  className="text-accent hover:text-accent underline transition-colors"
-                >
-                  clear the search
-                </button>
-                .
-              </p>
-            </div>
-          ) : (
-            <div className="flex flex-col items-center justify-center py-16 gap-3 text-center">
-              <span className="text-4xl text-ink-soft" aria-hidden="true">◇</span>
-              <p className="text-sm font-medium text-ink-mid">No {activeScope} memories</p>
-              <p className="text-[11px] text-ink-soft max-w-[200px] leading-relaxed">
-                {activeScope === "LOCAL"
-                  ? "This workspace has not written any local memories yet."
-                  : activeScope === "TEAM"
-                  ? "No team memories shared with this workspace yet."
-                  : "No global memories exist yet."}
-              </p>
-            </div>
-          )
+          <EmptyState query={debouncedQuery} pluginUnavailable={pluginUnavailable} />
         ) : (
           <div className="space-y-1.5">
             {entries.map((entry) => (
               <MemoryEntryRow
                 key={entry.id}
                 entry={entry}
-                onEdit={() => setEditorState({ mode: "edit", entry })}
                 onDelete={() => setPendingDeleteId(entry.id)}
               />
             ))}
@@ -336,36 +422,64 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
       {/* Delete confirmation dialog */}
       <ConfirmDialog
         open={pendingDeleteId !== null}
-        title="Delete memory"
-        message={`Delete this ${activeScope} memory? This cannot be undone.`}
-        confirmLabel="Delete"
+        title="Forget memory"
+        message="Forget this memory? This cannot be undone."
+        confirmLabel="Forget"
         confirmVariant="danger"
         onConfirm={confirmDelete}
         onCancel={() => setPendingDeleteId(null)}
       />
+    </div>
+  );
+}
 
-      {/* Add / Edit dialog */}
-      {editorState?.mode === "add" && (
-        <MemoryEditorDialog
-          open={true}
-          mode="add"
-          workspaceId={workspaceId}
-          defaultScope={activeScope}
-          defaultNamespace={activeNamespace || "general"}
-          onClose={() => setEditorState(null)}
-          onSaved={loadEntries}
-        />
-      )}
-      {editorState?.mode === "edit" && (
-        <MemoryEditorDialog
-          open={true}
-          mode="edit"
-          workspaceId={workspaceId}
-          entry={editorState.entry}
-          onClose={() => setEditorState(null)}
-          onSaved={loadEntries}
-        />
-      )}
+// ── Empty state ─────────────────────────────────────────────────────────────
+
+function EmptyState({
+  query,
+  pluginUnavailable,
+}: {
+  query: string;
+  pluginUnavailable: boolean;
+}) {
+  if (pluginUnavailable) {
+    // The banner already explains the problem; the empty rows just
+    // mirror it so the operator sees both signals.
+    return (
+      <div className="flex flex-col items-center justify-center py-16 gap-3 text-center">
+        <span className="text-4xl text-ink-soft" aria-hidden="true">
+          ◇
+        </span>
+        <p className="text-sm font-medium text-ink-mid">Memory plugin disabled</p>
+        <p className="text-[11px] text-ink-soft max-w-[220px] leading-relaxed">
+          See banner above for the operator-side fix.
+        </p>
+      </div>
+    );
+  }
+  if (query) {
+    return (
+      <div className="flex flex-col items-center justify-center py-16 gap-3 text-center">
+        <span className="text-4xl text-ink-soft" aria-hidden="true">
+          ◇
+        </span>
+        <p className="text-sm font-medium text-ink-mid">No memories match your search</p>
+        <p className="text-[11px] text-ink-soft max-w-[200px] leading-relaxed">
+          Try a different query or clear the search.
+        </p>
+      </div>
+    );
+  }
+  return (
+    <div className="flex flex-col items-center justify-center py-16 gap-3 text-center">
+      <span className="text-4xl text-ink-soft" aria-hidden="true">
+        ◇
+      </span>
+      <p className="text-sm font-medium text-ink-mid">No memories yet</p>
+      <p className="text-[11px] text-ink-soft max-w-[220px] leading-relaxed">
+        Agents commit memories via MCP tools (commit_memory, commit_summary). They
+        appear here once written.
+      </p>
     </div>
   );
 }
@@ -373,17 +487,32 @@ export function MemoryInspectorPanel({ workspaceId }: Props) {
 // ── MemoryEntryRow sub-component ──────────────────────────────────────────────
 
 interface MemoryEntryRowProps {
-  entry: MemoryEntry;
-  onEdit: () => void;
+  entry: MemoryV2;
   onDelete: () => void;
 }
 
-function MemoryEntryRow({ entry, onEdit, onDelete }: MemoryEntryRowProps) {
+const KIND_BADGE_CLASS: Record<MemoryKind, string> = {
+  fact: 'bg-surface-card text-ink-mid',
+  summary: 'bg-blue-950 text-accent',
+  checkpoint: 'bg-violet-950 text-violet-400',
+};
+
+const SOURCE_BADGE_CLASS: Record<MemorySource, string> = {
+  agent: 'bg-surface-card text-ink-mid',
+  runtime: 'bg-amber-950 text-amber-300',
+  user: 'bg-emerald-950 text-emerald-400',
+};
+
+function MemoryEntryRow({ entry, onDelete }: MemoryEntryRowProps) {
   const [expanded, setExpanded] = useState(false);
   const bodyId = `mem-body-${sanitizeId(entry.id)}`;
+  const ttl = formatTTL(entry.expires_at);
 
   return (
-    <div className="rounded-lg border border-line/60 bg-surface-sunken/50 overflow-hidden">
+    <div
+      className="rounded-lg border border-line/60 bg-surface-sunken/50 overflow-hidden"
+      data-testid={`memory-row-${entry.id}`}
+    >
       {/* Header row */}
       <button
         type="button"
@@ -392,52 +521,89 @@ function MemoryEntryRow({ entry, onEdit, onDelete }: MemoryEntryRowProps) {
         aria-expanded={expanded}
         aria-controls={bodyId}
       >
-        {/* Scope badge */}
+        {/* Kind badge */}
         <span
           className={[
-            "text-[9px] shrink-0 font-mono px-1 py-0.5 rounded",
-            entry.scope === "LOCAL"
-              ? "bg-surface-card text-ink-mid"
-              : entry.scope === "TEAM"
-              ? "bg-blue-950 text-accent"
-              : "bg-violet-950 text-violet-400",
-          ].join(" ")}
-          title={`Scope: ${entry.scope}`}
+            'text-[9px] shrink-0 font-mono px-1 py-0.5 rounded',
+            KIND_BADGE_CLASS[entry.kind] ?? 'bg-surface-card text-ink-mid',
+          ].join(' ')}
+          title={`Kind: ${entry.kind}`}
+          data-testid="kind-badge"
         >
-          {entry.scope[0]}
+          {entry.kind[0].toUpperCase()}
         </span>
 
+        {/* Source badge */}
+        <span
+          className={[
+            'text-[9px] shrink-0 font-mono px-1 py-0.5 rounded',
+            SOURCE_BADGE_CLASS[entry.source] ?? 'bg-surface-card text-ink-mid',
+          ].join(' ')}
+          title={`Source: ${entry.source}`}
+          data-testid="source-badge"
+        >
+          {entry.source}
+        </span>
+
+        {/* Pin indicator */}
+        {entry.pin && (
+          <span
+            className="text-[9px] shrink-0"
+            title="Pinned"
+            data-testid="pin-badge"
+            aria-label="Pinned"
+          >
+            📌
+          </span>
+        )}
+
         {/* Namespace tag */}
-        <span className="text-[9px] shrink-0 font-mono text-ink-soft truncate max-w-[80px]" title={entry.namespace}>
+        <span
+          className="text-[9px] shrink-0 font-mono text-ink-soft truncate max-w-[100px]"
+          title={entry.namespace}
+        >
           {entry.namespace}
         </span>
 
         {/* Content preview */}
         <span className="flex-1 min-w-0 text-[10px] font-mono text-ink-mid truncate text-left">
-          {entry.content.length > 60 ? entry.content.slice(0, 60) + "…" : entry.content}
+          {entry.content.length > 60 ? entry.content.slice(0, 60) + '…' : entry.content}
         </span>
 
-        {/* Similarity badge */}
-        {entry.similarity_score != null && (
+        {/* Score badge (semantic search only) */}
+        {entry.score != null && (
           <span
             className={[
-              "text-[9px] shrink-0 font-mono tabular-nums",
-              entry.similarity_score >= 0.8
-                ? "text-accent"
-                : "text-ink-mid",
-            ].join(" ")}
-            title={`Similarity: ${(entry.similarity_score * 100).toFixed(1)}%`}
-            data-testid="similarity-badge"
+              'text-[9px] shrink-0 font-mono tabular-nums',
+              entry.score >= 0.8 ? 'text-accent' : 'text-ink-mid',
+            ].join(' ')}
+            title={`Similarity: ${(entry.score * 100).toFixed(1)}%`}
+            data-testid="score-badge"
           >
-            {Math.round(entry.similarity_score * 100)}%
+            {Math.round(entry.score * 100)}%
           </span>
         )}
 
+        {/* TTL countdown */}
+        {ttl && (
+          <span
+            className={[
+              'text-[9px] shrink-0 font-mono',
+              ttl === 'expired' ? 'text-bad' : 'text-amber-400',
+            ].join(' ')}
+            title={`Expires: ${entry.expires_at}`}
+            data-testid="ttl-badge"
+          >
+            ⌛{ttl}
+          </span>
+        )}
+
+
         <span className="text-[9px] text-ink-soft shrink-0">
           {formatRelativeTime(entry.created_at)}
         </span>
         <span className="text-[9px] text-ink-soft shrink-0" aria-hidden="true">
-          {expanded ? "▼" : "▶"}
+          {expanded ? '▼' : '▶'}
         </span>
       </button>
 
@@ -455,31 +621,19 @@ function MemoryEntryRow({ entry, onEdit, onDelete }: MemoryEntryRowProps) {
           <div className="flex items-center justify-between gap-2">
             <span className="text-[9px] text-ink-soft">
               Created: {new Date(entry.created_at).toLocaleString()}
+              {entry.expires_at && ` · Expires: ${new Date(entry.expires_at).toLocaleString()}`}
             </span>
-            <div className="flex items-center gap-1.5 shrink-0">
-              <button
-                type="button"
-                onClick={(e) => {
-                  e.stopPropagation();
-                  onEdit();
-                }}
-                aria-label="Edit memory"
-                className="text-[10px] px-2 py-0.5 bg-surface-card hover:bg-surface-elevated border border-line/40 rounded text-ink-mid hover:text-ink transition-colors"
-              >
-                Edit
-              </button>
-              <button
-                type="button"
-                onClick={(e) => {
-                  e.stopPropagation();
-                  onDelete();
-                }}
-                aria-label="Delete memory"
-                className="text-[10px] px-2 py-0.5 bg-red-950/40 hover:bg-red-900/50 border border-red-900/30 rounded text-bad transition-colors"
-              >
-                Delete
-              </button>
-            </div>
+            <button
+              type="button"
+              onClick={(e) => {
+                e.stopPropagation();
+                onDelete();
+              }}
+              aria-label="Forget memory"
+              className="text-[10px] px-2 py-0.5 bg-red-950/40 hover:bg-red-900/50 border border-red-900/30 rounded text-bad transition-colors shrink-0"
+            >
+              Forget
+            </button>
           </div>
         </div>
       )}
diff --git a/canvas/src/components/__tests__/MemoryEditorDialog.test.tsx b/canvas/src/components/__tests__/MemoryEditorDialog.test.tsx
deleted file mode 100644
index 436bc649..00000000
--- a/canvas/src/components/__tests__/MemoryEditorDialog.test.tsx
+++ /dev/null
@@ -1,202 +0,0 @@
-// @vitest-environment jsdom
-/**
- * MemoryEditorDialog tests — covers Add (POST /memories) and Edit
- * (PATCH /memories/:id) flows. Pins:
- *   - Add posts {content, scope, namespace} with the trimmed defaults
- *   - Edit only sends fields that changed (no-op edit short-circuits, no PATCH fires)
- *   - Empty content blocks save
- *   - Save error surfaces in the dialog and keeps the modal open
- */
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
-import { render, screen, fireEvent, waitFor, cleanup } from "@testing-library/react";
-
-vi.mock("@/lib/api", () => ({
-  api: {
-    get: vi.fn(),
-    post: vi.fn(),
-    patch: vi.fn(),
-    del: vi.fn(),
-  },
-}));
-
-import { api } from "@/lib/api";
-import { MemoryEditorDialog } from "../MemoryEditorDialog";
-import type { MemoryEntry } from "../MemoryInspectorPanel";
-
-const mockPost = vi.mocked(api.post);
-const mockPatch = vi.mocked(api.patch);
-
-const SAMPLE: MemoryEntry = {
-  id: "mem-x",
-  workspace_id: "ws-1",
-  content: "original content",
-  scope: "TEAM",
-  namespace: "procedures",
-  created_at: "2026-04-17T12:00:00.000Z",
-};
-
-beforeEach(() => {
-  vi.clearAllMocks();
-  mockPost.mockResolvedValue({} as never);
-  mockPatch.mockResolvedValue({} as never);
-});
-
-afterEach(() => {
-  cleanup();
-});
-
-describe("Add mode", () => {
-  it("POSTs scope+namespace+trimmed-content and calls onSaved+onClose", async () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    render(
-      <MemoryEditorDialog
-        open
-        mode="add"
-        workspaceId="ws-1"
-        defaultScope="GLOBAL"
-        defaultNamespace="facts"
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-
-    const textarea = screen.getByLabelText(/Content/i) as HTMLTextAreaElement;
-    fireEvent.change(textarea, { target: { value: "  new fact  " } });
-
-    fireEvent.click(screen.getByRole("button", { name: /Add memory$/i }));
-
-    await waitFor(() => expect(mockPost).toHaveBeenCalledTimes(1));
-    expect(mockPost).toHaveBeenCalledWith("/workspaces/ws-1/memories", {
-      content: "new fact",
-      scope: "GLOBAL",
-      namespace: "facts",
-    });
-    expect(onSaved).toHaveBeenCalledTimes(1);
-    expect(onClose).toHaveBeenCalledTimes(1);
-  });
-
-  it("blocks save when content is empty (whitespace-only)", () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    render(
-      <MemoryEditorDialog
-        open
-        mode="add"
-        workspaceId="ws-1"
-        defaultScope="LOCAL"
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-    const textarea = screen.getByLabelText(/Content/i) as HTMLTextAreaElement;
-    fireEvent.change(textarea, { target: { value: "   " } });
-    fireEvent.click(screen.getByRole("button", { name: /Add memory$/i }));
-    expect(mockPost).not.toHaveBeenCalled();
-    expect(screen.getByRole("alert").textContent).toMatch(/empty/i);
-    expect(onSaved).not.toHaveBeenCalled();
-    expect(onClose).not.toHaveBeenCalled();
-  });
-});
-
-describe("Edit mode", () => {
-  it("PATCHes only changed fields", async () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    render(
-      <MemoryEditorDialog
-        open
-        mode="edit"
-        workspaceId="ws-1"
-        entry={SAMPLE}
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-
-    const textarea = screen.getByLabelText(/Content/i) as HTMLTextAreaElement;
-    fireEvent.change(textarea, { target: { value: "rewritten content" } });
-    // namespace untouched
-
-    fireEvent.click(screen.getByRole("button", { name: /Save changes/i }));
-
-    await waitFor(() => expect(mockPatch).toHaveBeenCalledTimes(1));
-    expect(mockPatch).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories/mem-x",
-      { content: "rewritten content" },
-    );
-    expect(onSaved).toHaveBeenCalledTimes(1);
-    expect(onClose).toHaveBeenCalledTimes(1);
-  });
-
-  it("no-op edit short-circuits (no PATCH fires) and still closes", async () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    render(
-      <MemoryEditorDialog
-        open
-        mode="edit"
-        workspaceId="ws-1"
-        entry={SAMPLE}
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-    fireEvent.click(screen.getByRole("button", { name: /Save changes/i }));
-    await waitFor(() => expect(onClose).toHaveBeenCalled());
-    expect(mockPatch).not.toHaveBeenCalled();
-    expect(onSaved).toHaveBeenCalledTimes(1);
-  });
-
-  it("sends namespace too when both content and namespace changed", async () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    render(
-      <MemoryEditorDialog
-        open
-        mode="edit"
-        workspaceId="ws-1"
-        entry={SAMPLE}
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-    fireEvent.change(screen.getByLabelText(/Content/i), {
-      target: { value: "newer content" },
-    });
-    fireEvent.change(screen.getByLabelText(/Namespace/i), {
-      target: { value: "blockers" },
-    });
-    fireEvent.click(screen.getByRole("button", { name: /Save changes/i }));
-    await waitFor(() => expect(mockPatch).toHaveBeenCalledTimes(1));
-    expect(mockPatch).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories/mem-x",
-      { content: "newer content", namespace: "blockers" },
-    );
-  });
-
-  it("surfaces save error and keeps the modal open", async () => {
-    const onClose = vi.fn();
-    const onSaved = vi.fn();
-    mockPatch.mockRejectedValueOnce(new Error("boom"));
-    render(
-      <MemoryEditorDialog
-        open
-        mode="edit"
-        workspaceId="ws-1"
-        entry={SAMPLE}
-        onClose={onClose}
-        onSaved={onSaved}
-      />,
-    );
-    fireEvent.change(screen.getByLabelText(/Content/i), {
-      target: { value: "rewritten content" },
-    });
-    fireEvent.click(screen.getByRole("button", { name: /Save changes/i }));
-    await waitFor(() =>
-      expect(screen.getByRole("alert").textContent).toMatch(/boom/),
-    );
-    expect(onClose).not.toHaveBeenCalled();
-    expect(onSaved).not.toHaveBeenCalled();
-  });
-});
diff --git a/canvas/src/components/__tests__/MemoryInspectorPanel.test.tsx b/canvas/src/components/__tests__/MemoryInspectorPanel.test.tsx
index 73cf2494..0111451f 100644
--- a/canvas/src/components/__tests__/MemoryInspectorPanel.test.tsx
+++ b/canvas/src/components/__tests__/MemoryInspectorPanel.test.tsx
@@ -1,16 +1,29 @@
 // @vitest-environment jsdom
 /**
- * MemoryInspectorPanel tests — issue #909
+ * MemoryInspectorPanel — v2 redesign tests.
  *
- * Covers: loading, empty state, scope tabs, namespace filter,
- * entry list, expand, delete flow, optimistic updates, Refresh, semantic search.
+ * Coverage targets every behavior the panel surfaces:
+ *   - Initial load wires GET /v2/namespaces + GET /v2/memories
+ *   - Plugin-unavailable banner (503) renders + disables interactions
+ *   - Generic error renders in the error banner
+ *   - Namespace dropdown populates from /v2/namespaces.readable; "All
+ *     namespaces" is the default
+ *   - Selecting a namespace re-fetches with ?namespace=...
+ *   - Search input debounces + scopes the request to ?q=
+ *   - Search results sort by score descending
+ *   - Empty-state copy differs by query / plugin-state / no-data
+ *   - Per-row badges render (kind / source / pin / TTL / score /
+ *     score) and TTL countdown handles past/future/null
+ *   - Delete (Forget) flow: optimistic removal, confirmation dialog,
+ *     server failure rolls back via reload
+ *   - formatTTL helper covers s/m/h/d/expired/null/invalid branches
  */
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
-import { render, screen, fireEvent, waitFor, cleanup, act } from "@testing-library/react";
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { render, screen, fireEvent, waitFor, cleanup } from '@testing-library/react';
 
 // ── Mocks ─────────────────────────────────────────────────────────────────────
 
-vi.mock("@/lib/api", () => ({
+vi.mock('@/lib/api', () => ({
   api: {
     get: vi.fn(),
     post: vi.fn(),
@@ -18,7 +31,7 @@ vi.mock("@/lib/api", () => ({
   },
 }));
 
-vi.mock("@/components/ConfirmDialog", () => ({
+vi.mock('@/components/ConfirmDialog', () => ({
   ConfirmDialog: ({
     open,
     title,
@@ -33,435 +46,473 @@ vi.mock("@/components/ConfirmDialog", () => ({
     confirmVariant?: string;
     onConfirm: () => void;
     onCancel: () => void;
-    singleButton?: boolean;
   }) =>
     open ? (
       <div data-testid="confirm-dialog">
         <p data-testid="dialog-title">{title}</p>
         <p data-testid="dialog-message">{message}</p>
-        <button onClick={onConfirm}>Confirm Delete</button>
-        <button onClick={onCancel}>Cancel Delete</button>
+        <button onClick={onConfirm}>Confirm</button>
+        <button onClick={onCancel}>Cancel</button>
       </div>
     ) : null,
 }));
 
-import { api } from "@/lib/api";
-import { MemoryInspectorPanel } from "../MemoryInspectorPanel";
-
-// ── Typed mock helpers ────────────────────────────────────────────────────────
+import { api } from '@/lib/api';
+import {
+  MemoryInspectorPanel,
+  formatTTL,
+  isPluginUnavailableError,
+  type MemoryV2,
+  type NamespacesResponse,
+} from '../MemoryInspectorPanel';
 
 const mockGet = vi.mocked(api.get);
 const mockDel = vi.mocked(api.del);
 
-// ── Sample fixtures ───────────────────────────────────────────────────────────
+// ── Fixtures ──────────────────────────────────────────────────────────────────
 
-const NOW = "2026-04-17T12:00:00.000Z";
-
-const MEMORY_A: import("../MemoryInspectorPanel").MemoryEntry = {
-  id: "mem-a",
-  workspace_id: "ws-1",
-  content: "Remember to review PRs before merging",
-  scope: "LOCAL",
-  namespace: "general",
-  created_at: NOW,
+const NS_RESPONSE: NamespacesResponse = {
+  readable: [
+    { name: 'workspace:ws-1', kind: 'workspace', label: 'Workspace (ws-1)' },
+    { name: 'team:t-1', kind: 'team', label: 'Team (t-1)' },
+  ],
+  writable: [{ name: 'workspace:ws-1', kind: 'workspace', label: 'Workspace (ws-1)' }],
 };
 
-const MEMORY_B: import("../MemoryInspectorPanel").MemoryEntry = {
-  id: "mem-b",
-  workspace_id: "ws-1",
-  content: "Team knowledge: deploy happens on Fridays",
-  scope: "TEAM",
-  namespace: "procedures",
-  created_at: NOW,
+const MEM_BASIC: MemoryV2 = {
+  id: 'mem-a',
+  namespace: 'workspace:ws-1',
+  content: 'Remember the standup is at 10am',
+  kind: 'fact',
+  source: 'agent',
+  pin: false,
+  created_at: '2026-04-17T12:00:00.000Z',
 };
 
-const TWO_MEMORIES = [MEMORY_A, MEMORY_B];
+const MEM_PINNED: MemoryV2 = {
+  id: 'mem-pinned',
+  namespace: 'team:t-1',
+  content: 'Team retro every Friday',
+  kind: 'summary',
+  source: 'user',
+  pin: true,
+  expires_at: new Date(Date.now() + 86_400_000).toISOString(),
+  created_at: '2026-04-17T12:00:00.000Z',
+};
+
+const MEM_RUNTIME_CHECKPOINT: MemoryV2 = {
+  id: 'mem-checkpoint',
+  namespace: 'team:t-1',
+  content: 'Runtime checkpoint',
+  kind: 'checkpoint',
+  source: 'runtime',
+  pin: false,
+  created_at: '2026-04-17T12:00:00.000Z',
+};
+
+const MEM_EXPIRED: MemoryV2 = {
+  id: 'mem-expired',
+  namespace: 'workspace:ws-1',
+  content: 'Stale memory',
+  kind: 'fact',
+  source: 'agent',
+  pin: false,
+  expires_at: new Date(Date.now() - 1000).toISOString(),
+  created_at: '2026-04-17T12:00:00.000Z',
+};
 
 // ── Setup / teardown ──────────────────────────────────────────────────────────
 
 beforeEach(() => {
-  vi.clearAllMocks();
+  mockGet.mockReset();
+  mockDel.mockReset();
 });
 
 afterEach(() => {
   cleanup();
 });
 
-// ── Helper: flush microtasks + React state updates ─────────────────────────────
-async function flushUpdates(): Promise<void> {
-  await act(async () => {});
+// Helper: stub a basic two-call flow (namespaces + memories).
+function stubFetch(memories: MemoryV2[], namespaces: NamespacesResponse = NS_RESPONSE) {
+  mockGet.mockImplementation(((url: string) => {
+    if (url.includes('/v2/namespaces')) {
+      return Promise.resolve(namespaces);
+    }
+    return Promise.resolve({ memories });
+  }) as typeof api.get);
 }
 
-// ── Loading & empty state ─────────────────────────────────────────────────────
+// ── isPluginUnavailableError helper ─────────────────────────────────────────
 
-describe("MemoryInspectorPanel — loading and empty state", () => {
-  it("shows loading indicator before data arrives", () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockReturnValue(new Promise(() => {}) as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    expect(screen.getByText(/loading memories/i)).toBeTruthy();
-  });
-
-  it("renders empty state when API returns []", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByText("No LOCAL memories")).toBeTruthy();
-  });
-
-  it("fetches from the correct workspace memories endpoint with scope=LOCAL", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-abc-123" />);
-    await flushUpdates();
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-abc-123/memories?scope=LOCAL"
-    );
-  });
-
-  it("shows error banner when fetch throws", async () => {
-    mockGet.mockRejectedValue(new Error("Network error"));
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByText("Network error")).toBeTruthy();
-  });
-});
-
-// ── Scope tabs ────────────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — scope tabs", () => {
-  it("renders LOCAL, TEAM, GLOBAL tabs", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByRole("button", { name: "LOCAL" })).toBeTruthy();
-    expect(screen.getByRole("button", { name: "TEAM" })).toBeTruthy();
-    expect(screen.getByRole("button", { name: "GLOBAL" })).toBeTruthy();
-  });
-
-  it("LOCAL is active by default", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByRole("button", { name: "LOCAL" }).getAttribute("aria-pressed")).toBe("true");
-  });
-
-  it("clicking TEAM tab re-fetches with scope=TEAM", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    mockGet.mockClear();
-    fireEvent.click(screen.getByRole("button", { name: "TEAM" }));
-    await flushUpdates();
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories?scope=TEAM"
-    );
-  });
-
-  it("clicking GLOBAL tab re-fetches with scope=GLOBAL", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    mockGet.mockClear();
-    fireEvent.click(screen.getByRole("button", { name: "GLOBAL" }));
-    await flushUpdates();
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories?scope=GLOBAL"
-    );
-  });
-
-  it("shows scope-specific empty state when switching tabs", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    fireEvent.click(screen.getByRole("button", { name: "TEAM" }));
-    await flushUpdates();
-    expect(screen.getByText("No TEAM memories")).toBeTruthy();
-  });
-});
-
-// ── Namespace filter ──────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — namespace filter", () => {
-  it("renders namespace filter input", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByLabelText("Filter by namespace")).toBeTruthy();
-  });
-
-  it("includes namespace param in API call when set", async () => {
-    vi.useFakeTimers();
-    try {
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-      mockGet.mockResolvedValue([] as any);
-      render(<MemoryInspectorPanel workspaceId="ws-1" />);
-      await flushUpdates();
-
-      mockGet.mockClear();
-      fireEvent.change(screen.getByLabelText("Filter by namespace"), {
-        target: { value: "facts" },
-      });
-      // Advance past the 300ms debounce
-      act(() => { vi.advanceTimersByTime(350); });
-      await flushUpdates();
-
-      expect(mockGet).toHaveBeenCalledWith(
-        "/workspaces/ws-1/memories?scope=LOCAL&namespace=facts"
-      );
-    } finally {
-      vi.useRealTimers();
-    }
-  });
-});
-
-// ── Entry list ───────────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — entry list", () => {
-  beforeEach(() => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue(TWO_MEMORIES as any);
-  });
-
-  it("renders a row for every memory", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByText(/Remember to review PRs before merging/)).toBeTruthy();
-    expect(screen.getByText(/Team knowledge: deploy happens on Fridays/)).toBeTruthy();
-  });
-
-  it("displays memory count in toolbar", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByText("2 memories")).toBeTruthy();
-  });
-
-  it("displays scope badge for each entry", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByTitle("Scope: LOCAL")).toBeTruthy();
-    expect(screen.getByTitle("Scope: TEAM")).toBeTruthy();
-  });
-
-  it("entries are collapsed by default (pre region not visible)", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    // Expanded region (pre tag) should not exist in DOM yet
-    expect(screen.queryByRole("region")).toBeNull();
-  });
-});
-
-// ── Expand / collapse ─────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — expand/collapse", () => {
-  beforeEach(() => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue(TWO_MEMORIES as any);
-  });
-
-  it("clicking a row header expands it and shows the full content in a pre tag", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    fireEvent.click(
-      screen.getByText(/Remember to review PRs before merging/).closest("button")!
-    );
-    await flushUpdates();
-    // After expand, a region with the full content <pre> should appear
-    expect(screen.getByRole("region")).toBeTruthy();
-  });
-
-  it("clicking the header again collapses the row (pre region removed)", async () => {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    const headerBtn = screen
-      .getByText(/Remember to review PRs before merging/)
-      .closest("button")!;
-    fireEvent.click(headerBtn); // expand
-    await flushUpdates();
-    expect(screen.getByRole("region")).toBeTruthy();
-
-    fireEvent.click(headerBtn); // collapse
-    await flushUpdates();
-    // After collapse, the region (pre) is removed from the DOM
-    expect(screen.queryByRole("region")).toBeNull();
-  });
-});
-
-// ── Delete flow ───────────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — delete flow", () => {
-  beforeEach(() => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue(TWO_MEMORIES as any);
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockDel.mockResolvedValue({ status: "deleted" } as any);
-  });
-
-  /** Helper: expand memory-A and click its Delete button */
-  async function openDeleteForMemoryA() {
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    fireEvent.click(
-      screen.getByText(/Remember to review PRs before merging/).closest("button")!
-    );
-    await flushUpdates();
-    fireEvent.click(screen.getByRole("button", { name: "Delete memory" }));
-    await flushUpdates();
-  }
-
-  it("opens ConfirmDialog when Delete is clicked", async () => {
-    await openDeleteForMemoryA();
-    expect(screen.getByTestId("confirm-dialog")).toBeTruthy();
-    expect(screen.getByTestId("dialog-title").textContent).toBe("Delete memory");
-  });
-
-  it("calls api.del with the correct URL-encoded path on confirm", async () => {
-    await openDeleteForMemoryA();
-    fireEvent.click(screen.getByText("Confirm Delete"));
-    await flushUpdates();
-    expect(mockDel).toHaveBeenCalledWith("/workspaces/ws-1/memories/mem-a");
-  });
-
-  it("removes the entry optimistically after confirm", async () => {
-    await openDeleteForMemoryA();
-    fireEvent.click(screen.getByText("Confirm Delete"));
-    await flushUpdates();
-    expect(screen.queryByText(/Remember to review PRs before merging/)).toBeNull();
-    // Sibling entry unaffected
-    expect(screen.getByText(/Team knowledge: deploy happens on Fridays/)).toBeTruthy();
-  });
-
-  it("closes ConfirmDialog without deleting when Cancel is clicked", async () => {
-    await openDeleteForMemoryA();
-    fireEvent.click(screen.getByText("Cancel Delete"));
-    await flushUpdates();
-    expect(screen.queryByTestId("confirm-dialog")).toBeNull();
-    expect(mockDel).not.toHaveBeenCalled();
-    // Sibling memory entry (MEMORY_B) is still in the list
-    expect(screen.getByText(/Team knowledge: deploy happens on Fridays/)).toBeTruthy();
-  });
-});
-
-// ── Refresh ───────────────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — Refresh button", () => {
-  it("re-fetches entries when Refresh is clicked", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    expect(screen.getByText("No LOCAL memories")).toBeTruthy();
-
-    expect(mockGet).toHaveBeenCalledTimes(1);
-    fireEvent.click(screen.getByRole("button", { name: "Refresh memories" }));
-    await flushUpdates();
-    expect(mockGet).toHaveBeenCalledTimes(2);
-  });
-});
-
-// ── role=alert a11y ──────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — error elements have role=alert", () => {
-  it("fetch error banner has role='alert'", async () => {
-    mockGet.mockRejectedValue(new Error("Network error"));
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    const alert = screen.getByRole("alert");
-    expect(alert).toBeTruthy();
-    expect(alert.textContent).toContain("Network error");
-  });
-});
-
-// ── Semantic search ──────────────────────────────────────────────────────────
-
-describe("MemoryInspectorPanel — semantic search", () => {
-  afterEach(() => {
-    vi.useRealTimers();
-  });
-
-  it("debounces search input by 300ms before calling API", async () => {
-    vi.useFakeTimers();
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-
-    mockGet.mockClear();
-
-    fireEvent.change(screen.getByLabelText("Search memories"), {
-      target: { value: "deploy" },
-    });
-
-    // 200ms — debounce has NOT fired yet
-    act(() => { vi.advanceTimersByTime(200); });
-    await flushUpdates();
-    expect(mockGet).not.toHaveBeenCalled();
-
-    // 350ms total — debounce fires
-    act(() => { vi.advanceTimersByTime(150); });
-    await flushUpdates();
-
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories?scope=LOCAL&q=deploy"
-    );
-  });
-
-  it("renders similarity-badge when entry has similarity_score", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([{ ...MEMORY_A, similarity_score: 0.87 }] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
-    const badge = document.querySelector('[data-testid="similarity-badge"]');
-    expect(badge).toBeTruthy();
-    expect(badge?.textContent).toBe("87%");
-  });
-
-  it("does not render similarity-badge when entry has no similarity_score", async () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([MEMORY_A] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
+describe('isPluginUnavailableError', () => {
+  it('matches the literal env var contract from the server handler', () => {
     expect(
-      document.querySelector('[data-testid="similarity-badge"]')
-    ).toBeNull();
+      isPluginUnavailableError(
+        new Error('API GET /workspaces/x/v2/memories: 503 {"error":"memory plugin is not configured (set MEMORY_PLUGIN_URL)"}'),
+      ),
+    ).toBe(true);
   });
 
-  it("clear button resets query immediately and re-fetches without ?q=", async () => {
-    vi.useFakeTimers();
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    mockGet.mockResolvedValue([] as any);
-    render(<MemoryInspectorPanel workspaceId="ws-1" />);
-    await flushUpdates();
+  it('does not false-match on generic 503 errors that don\'t mention the env var', () => {
+    expect(isPluginUnavailableError(new Error('API GET /foo: 503 something else'))).toBe(false);
+  });
 
-    fireEvent.change(screen.getByLabelText("Search memories"), {
-      target: { value: "deploy" },
+  it('does not false-match on plain 4xx errors', () => {
+    expect(isPluginUnavailableError(new Error('API GET /foo: 401 unauthorized'))).toBe(false);
+  });
+
+  it('returns false for non-Error inputs', () => {
+    expect(isPluginUnavailableError(null)).toBe(false);
+    expect(isPluginUnavailableError(undefined)).toBe(false);
+    expect(isPluginUnavailableError('a string')).toBe(false);
+    expect(isPluginUnavailableError({ message: 'MEMORY_PLUGIN_URL' })).toBe(false);
+  });
+});
+
+// ── formatTTL helper ─────────────────────────────────────────────────────────
+
+describe('formatTTL', () => {
+  it('returns empty string for null/undefined/empty', () => {
+    expect(formatTTL(null)).toBe('');
+    expect(formatTTL(undefined)).toBe('');
+    expect(formatTTL('')).toBe('');
+  });
+
+  it('returns empty for invalid date strings', () => {
+    expect(formatTTL('not-a-date')).toBe('');
+  });
+
+  it('returns "expired" for past timestamps', () => {
+    const past = new Date(Date.now() - 5000).toISOString();
+    expect(formatTTL(past)).toBe('expired');
+  });
+
+  it('formats <60s as seconds', () => {
+    const future = new Date(Date.now() + 30_000).toISOString();
+    expect(formatTTL(future)).toMatch(/^\d{1,2}s$/);
+  });
+
+  it('formats <60m as minutes', () => {
+    const future = new Date(Date.now() + 30 * 60_000).toISOString();
+    expect(formatTTL(future)).toMatch(/^\d{1,2}m$/);
+  });
+
+  it('formats <24h as hours', () => {
+    const future = new Date(Date.now() + 5 * 3_600_000).toISOString();
+    expect(formatTTL(future)).toMatch(/^\d{1,2}h$/);
+  });
+
+  it('formats >24h as days', () => {
+    const future = new Date(Date.now() + 3 * 86_400_000).toISOString();
+    expect(formatTTL(future)).toMatch(/^\d{1,2}d$/);
+  });
+});
+
+// ── Initial load + dropdown ─────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — initial load', () => {
+  it('fetches namespaces and memories on mount', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+
+    await waitFor(() => {
+      const calls = mockGet.mock.calls.map((c) => c[0]);
+      expect(calls.some((u) => u.includes('/v2/namespaces'))).toBe(true);
+      expect(calls.some((u) => u.includes('/v2/memories'))).toBe(true);
+    });
+  });
+
+  it('renders the row contents from the memories response', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText(/Remember the standup is at 10am/)).toBeTruthy();
+    });
+  });
+
+  it('populates the namespace dropdown with readable entries + "All namespaces"', async () => {
+    stubFetch([]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Filter by namespace'));
+    const select = screen.getByLabelText('Filter by namespace') as HTMLSelectElement;
+    const optionLabels = Array.from(select.options).map((o) => o.textContent ?? '');
+    expect(optionLabels[0]).toContain('All namespaces');
+    expect(optionLabels.join('|')).toContain('Workspace (ws-1)');
+    expect(optionLabels.join('|')).toContain('Team (t-1)');
+  });
+
+  it('selecting a namespace re-fetches with ?namespace=', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Filter by namespace'));
+
+    const select = screen.getByLabelText('Filter by namespace') as HTMLSelectElement;
+    fireEvent.change(select, { target: { value: 'team:t-1' } });
+
+    await waitFor(() => {
+      const calls = mockGet.mock.calls.map((c) => c[0] as string);
+      expect(calls.some((u) => u.includes('namespace=team%3At-1'))).toBe(true);
+    });
+  });
+});
+
+// ── Plugin unavailable (503) ────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — plugin unavailable', () => {
+  it('renders the operator-hint banner and disables search input', async () => {
+    mockGet.mockRejectedValue(new Error('HTTP 503: memory plugin is not configured (set MEMORY_PLUGIN_URL)'));
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByTestId('plugin-unavailable-banner'));
+
+    const searchInput = screen.getByLabelText('Search memories') as HTMLInputElement;
+    expect(searchInput.disabled).toBe(true);
+  });
+
+  it('shows the empty-state explaining plugin disabled', async () => {
+    mockGet.mockRejectedValue(new Error('API GET /workspaces/x/v2/memories: 503 {"error":"memory plugin is not configured (set MEMORY_PLUGIN_URL)"}'));
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText(/Memory plugin disabled/i));
+  });
+});
+
+// ── Generic error (non-503) ─────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — generic errors', () => {
+  it('surfaces a non-503 error in the error banner', async () => {
+    mockGet.mockImplementation(((url: string) => {
+      if (url.includes('/v2/namespaces')) {
+        return Promise.resolve(NS_RESPONSE);
+      }
+      return Promise.reject(new Error('upstream timeout'));
+    }) as typeof api.get);
+
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => {
+      // Error banner has role=alert
+      const alerts = screen.getAllByRole('alert');
+      const found = alerts.some((a) => a.textContent?.includes('upstream timeout'));
+      expect(found).toBe(true);
+    });
+  });
+});
+
+// ── Search ──────────────────────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — search', () => {
+  it('eventually fires query with ?q= after debounce', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Search memories'));
+
+    fireEvent.change(screen.getByLabelText('Search memories'), {
+      target: { value: 'standup' },
     });
 
-    act(() => { vi.advanceTimersByTime(350); });
-    await flushUpdates();
-
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories?scope=LOCAL&q=deploy"
+    await waitFor(
+      () => {
+        const calls = mockGet.mock.calls.map((c) => c[0] as string);
+        expect(calls.some((u) => u.includes('q=standup'))).toBe(true);
+      },
+      { timeout: 1500 },
     );
-    mockGet.mockClear();
+  });
 
-    fireEvent.click(screen.getByRole("button", { name: "Clear search" }));
-    await flushUpdates();
+  it('sorts results by score descending when query active', async () => {
+    const lowScore: MemoryV2 = { ...MEM_BASIC, id: 'low', score: 0.2, content: 'low' };
+    const highScore: MemoryV2 = { ...MEM_BASIC, id: 'high', score: 0.95, content: 'high' };
+    // Plugin returns in arbitrary order; component sorts.
+    mockGet.mockImplementation(((url: string) => {
+      if (url.includes('/v2/namespaces')) return Promise.resolve(NS_RESPONSE);
+      return Promise.resolve({ memories: [lowScore, highScore] });
+    }) as typeof api.get);
 
-    expect(mockGet).toHaveBeenCalledWith(
-      "/workspaces/ws-1/memories?scope=LOCAL"
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Search memories'));
+    fireEvent.change(screen.getByLabelText('Search memories'), {
+      target: { value: 'something' },
+    });
+
+    await waitFor(
+      () => {
+        const rows = screen.getAllByTestId(/^memory-row-/);
+        // First row should be the high-score one
+        expect(rows[0].getAttribute('data-testid')).toBe('memory-row-high');
+      },
+      { timeout: 1500 },
+    );
+  });
+
+  it('clear-button resets the query', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Search memories'));
+
+    fireEvent.change(screen.getByLabelText('Search memories'), {
+      target: { value: 'foo' },
+    });
+    fireEvent.click(screen.getByLabelText('Clear search'));
+    expect((screen.getByLabelText('Search memories') as HTMLInputElement).value).toBe('');
+  });
+
+  it('renders no-results empty-state when search has no matches', async () => {
+    stubFetch([]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Search memories'));
+    fireEvent.change(screen.getByLabelText('Search memories'), {
+      target: { value: 'nothing' },
+    });
+    await waitFor(
+      () => {
+        expect(screen.getByText(/No memories match your search/i)).toBeTruthy();
+      },
+      { timeout: 1500 },
     );
   });
 });
+
+// ── Per-row badges ───────────────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — row badges', () => {
+  it('renders kind, source, pin, TTL badges per shape', async () => {
+    stubFetch([MEM_PINNED, MEM_RUNTIME_CHECKPOINT]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+
+    await waitFor(() => {
+      // Pinned memory: kind=summary, source=user, pin=true, TTL>0
+      const pinnedRow = screen.getByTestId('memory-row-mem-pinned');
+      expect(pinnedRow.querySelector('[data-testid="kind-badge"]')?.textContent).toBe('S');
+      expect(pinnedRow.querySelector('[data-testid="source-badge"]')?.textContent).toBe('user');
+      expect(pinnedRow.querySelector('[data-testid="pin-badge"]')).toBeTruthy();
+      expect(pinnedRow.querySelector('[data-testid="ttl-badge"]')?.textContent).toMatch(/^⌛\d+[hd]$/);
+
+      // Checkpoint memory: kind=checkpoint, source=runtime, no pin, no TTL
+      const propRow = screen.getByTestId('memory-row-mem-checkpoint');
+      expect(propRow.querySelector('[data-testid="kind-badge"]')?.textContent).toBe('C');
+      expect(propRow.querySelector('[data-testid="source-badge"]')?.textContent).toBe('runtime');
+      expect(propRow.querySelector('[data-testid="pin-badge"]')).toBeNull();
+      expect(propRow.querySelector('[data-testid="ttl-badge"]')).toBeNull();
+    });
+  });
+
+  it('TTL badge shows "expired" for past expires_at', async () => {
+    stubFetch([MEM_EXPIRED]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => {
+      const row = screen.getByTestId('memory-row-mem-expired');
+      expect(row.querySelector('[data-testid="ttl-badge"]')?.textContent).toBe('⌛expired');
+    });
+  });
+
+  it('expanding a row shows full content + Forget button', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByTestId('memory-row-mem-a'));
+
+    const row = screen.getByTestId('memory-row-mem-a');
+    const headerButton = row.querySelector('button');
+    expect(headerButton).toBeTruthy();
+    fireEvent.click(headerButton!);
+
+    await waitFor(() => {
+      expect(screen.getByLabelText('Forget memory')).toBeTruthy();
+    });
+  });
+});
+
+// ── Delete (Forget) flow ──────────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — forget flow', () => {
+  it('opens the confirm dialog on Forget click and removes optimistically on confirm', async () => {
+    stubFetch([MEM_BASIC]);
+    mockDel.mockResolvedValue({ status: 'deleted' });
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+
+    // Expand row, click Forget
+    await waitFor(() => screen.getByTestId('memory-row-mem-a'));
+    const row = screen.getByTestId('memory-row-mem-a');
+    fireEvent.click(row.querySelector('button')!);
+    await waitFor(() => screen.getByLabelText('Forget memory'));
+    fireEvent.click(screen.getByLabelText('Forget memory'));
+
+    // Dialog appears with v2-shaped copy (Forget, not Delete)
+    expect(screen.getByTestId('dialog-title').textContent).toBe('Forget memory');
+    fireEvent.click(screen.getByText('Confirm'));
+
+    // Optimistic removal happens immediately
+    await waitFor(() => {
+      expect(screen.queryByTestId('memory-row-mem-a')).toBeNull();
+    });
+    // DELETE called with the right path
+    await waitFor(() => {
+      const delPaths = mockDel.mock.calls.map((c) => c[0] as string);
+      expect(delPaths.some((p) => p.includes('/v2/memories/mem-a'))).toBe(true);
+    });
+  });
+
+  it('cancelling the dialog leaves the row in place', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByTestId('memory-row-mem-a'));
+
+    fireEvent.click(screen.getByTestId('memory-row-mem-a').querySelector('button')!);
+    await waitFor(() => screen.getByLabelText('Forget memory'));
+    fireEvent.click(screen.getByLabelText('Forget memory'));
+    fireEvent.click(screen.getByText('Cancel'));
+
+    expect(screen.queryByTestId('memory-row-mem-a')).toBeTruthy();
+    expect(mockDel).not.toHaveBeenCalled();
+  });
+
+  it('rolls back on server failure by reloading entries', async () => {
+    stubFetch([MEM_BASIC]);
+    mockDel.mockRejectedValue(new Error('upstream 502'));
+
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByTestId('memory-row-mem-a'));
+    fireEvent.click(screen.getByTestId('memory-row-mem-a').querySelector('button')!);
+    await waitFor(() => screen.getByLabelText('Forget memory'));
+    fireEvent.click(screen.getByLabelText('Forget memory'));
+    fireEvent.click(screen.getByText('Confirm'));
+
+    // After failure, error banner surfaces + reload re-fetches memories
+    await waitFor(() => {
+      const alerts = screen.getAllByRole('alert');
+      const found = alerts.some((a) => a.textContent?.includes('upstream 502'));
+      expect(found).toBe(true);
+    });
+  });
+});
+
+// ── Empty state when no memories at all ────────────────────────────────────
+
+describe('MemoryInspectorPanel — empty state', () => {
+  it('renders the "no memories yet" empty state when not searching', async () => {
+    stubFetch([]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText('No memories yet')).toBeTruthy();
+    });
+  });
+});
+
+// ── Refresh ─────────────────────────────────────────────────────────────────
+
+describe('MemoryInspectorPanel — refresh', () => {
+  it('Refresh button refetches memories', async () => {
+    stubFetch([MEM_BASIC]);
+    render(<MemoryInspectorPanel workspaceId="ws-1" />);
+    await waitFor(() => screen.getByLabelText('Refresh memories'));
+
+    const before = mockGet.mock.calls.filter((c) =>
+      (c[0] as string).includes('/v2/memories'),
+    ).length;
+    fireEvent.click(screen.getByLabelText('Refresh memories'));
+
+    await waitFor(() => {
+      const after = mockGet.mock.calls.filter((c) =>
+        (c[0] as string).includes('/v2/memories'),
+      ).length;
+      expect(after).toBe(before + 1);
+    });
+  });
+});
diff --git a/canvas/src/components/tabs/ChatTab.tsx b/canvas/src/components/tabs/ChatTab.tsx
index 2d6ae908..2bc3939f 100644
--- a/canvas/src/components/tabs/ChatTab.tsx
+++ b/canvas/src/components/tabs/ChatTab.tsx
@@ -7,7 +7,7 @@ import { api } from "@/lib/api";
 import { useCanvasStore, type WorkspaceNodeData } from "@/store/canvas";
 import { useSocketEvent } from "@/hooks/useSocketEvent";
 import { type ChatMessage, type ChatAttachment, createMessage, appendMessageDeduped } from "./chat/types";
-import { uploadChatFiles, downloadChatFile } from "./chat/uploads";
+import { uploadChatFiles, downloadChatFile, isPlatformAttachment } from "./chat/uploads";
 import { AttachmentChip, PendingAttachmentPill } from "./chat/AttachmentViews";
 import { extractFilesFromTask } from "./chat/message-parser";
 import { AgentCommsPanel } from "./chat/AgentCommsPanel";
@@ -1061,7 +1061,77 @@ function MyChatPanel({ workspaceId, data }: Props) {
                       : "dark:prose-invert dark:[--tw-prose-invert-body:theme(colors.zinc.100)] dark:[--tw-prose-invert-headings:theme(colors.white)] dark:[--tw-prose-invert-bold:theme(colors.white)] dark:[--tw-prose-invert-code:theme(colors.zinc.100)]"
                   }`}
                 >
-                  <ReactMarkdown remarkPlugins={[remarkGfm]}>{msg.content}</ReactMarkdown>
+                  <ReactMarkdown
+                    remarkPlugins={[remarkGfm]}
+                    components={{
+                      // Default ReactMarkdown renders `<a href="...">`
+                      // with no target and no scheme handling, so:
+                      //
+                      //   1. http/https links navigate the canvas tab
+                      //      itself away — user loses canvas state.
+                      //   2. workspace://, file://, and bare /workspace/
+                      //      paths from agent-authored markdown produce
+                      //      an unhandled-protocol click → browser ends
+                      //      up at about:blank with no download (the
+                      //      reported bug from 2026-05-05).
+                      //
+                      // Override: external URLs open in a new tab with
+                      // rel="noopener noreferrer"; in-container paths
+                      // route through downloadChatFile so the browser
+                      // gets a real Blob with proper auth headers.
+                      a: ({ href, children, ...rest }) => {
+                        const url = String(href ?? "");
+                        // Use the SSOT helper isPlatformAttachment so
+                        // the markdown link override and the chip
+                        // download path agree on which schemes need
+                        // auth-routed download. Pre-fix this list was
+                        // duplicated and missed `platform-pending:`,
+                        // producing about:blank for poll-mode uploads.
+                        if (isPlatformAttachment(url)) {
+                          return (
+                            <a
+                              href={url}
+                              {...rest}
+                              onClick={(e) => {
+                                e.preventDefault();
+                                // Construct a synthetic ChatAttachment
+                                // and route through the same
+                                // authenticated download path the
+                                // download chips use. Filename is the
+                                // last path segment so Save-As prefills
+                                // sensibly.
+                                const name = url.split(/[\\/]/).pop() || "download";
+                                downloadChatFile(workspaceId, {
+                                  uri: url,
+                                  name,
+                                }).catch((err) => {
+                                  setError(
+                                    err instanceof Error
+                                      ? `Download failed: ${err.message}`
+                                      : "Download failed",
+                                  );
+                                });
+                              }}
+                            >
+                              {children}
+                            </a>
+                          );
+                        }
+                        // External (http(s) / mailto / unknown scheme):
+                        // open in new tab so canvas state survives.
+                        return (
+                          <a
+                            href={url}
+                            target="_blank"
+                            rel="noopener noreferrer"
+                            {...rest}
+                          >
+                            {children}
+                          </a>
+                        );
+                      },
+                    }}
+                  >{msg.content}</ReactMarkdown>
                 </div>
               )}
               {msg.attachments && msg.attachments.length > 0 && (
@@ -1167,7 +1237,22 @@ function MyChatPanel({ workspaceId, data }: Props) {
             value={input}
             onChange={(e) => setInput(e.target.value)}
             onKeyDown={(e) => {
-              if (e.key === "Enter" && !e.shiftKey) {
+              // IME-safe send: while a CJK / Japanese / Korean IME is
+              // composing, Enter accepts the candidate selection — not a
+              // newline, not a send. `e.nativeEvent.isComposing` is the
+              // standard signal (modern WebKit/Blink/Gecko); the keyCode
+              // 229 fallback covers older Safari / WebKit-based mobile
+              // browsers that delay setting isComposing on the
+              // composition-end Enter. Reported 2026-05-05: typing
+              // Chinese with the system IME, pressing Enter to commit
+              // a candidate would inadvertently send the half-typed
+              // message.
+              if (
+                e.key === "Enter" &&
+                !e.shiftKey &&
+                !e.nativeEvent.isComposing &&
+                e.keyCode !== 229
+              ) {
                 e.preventDefault();
                 sendMessage();
               }
diff --git a/canvas/src/components/tabs/__tests__/ChatTab.imeAndLinks.test.tsx b/canvas/src/components/tabs/__tests__/ChatTab.imeAndLinks.test.tsx
new file mode 100644
index 00000000..d71e8ada
--- /dev/null
+++ b/canvas/src/components/tabs/__tests__/ChatTab.imeAndLinks.test.tsx
@@ -0,0 +1,141 @@
+// @vitest-environment jsdom
+//
+// Pins two regressions reported on production 2026-05-05:
+//
+// 1. IME composition + Enter key: typing Chinese (or any CJK / IME-
+//    composed text) and pressing Enter to commit the candidate
+//    selection used to send the half-typed message. The fix checks
+//    `event.nativeEvent.isComposing` (and a `keyCode === 229`
+//    fallback for older WebKit) before treating Enter as send.
+//
+// 2. Markdown link clicks: the agent's ReactMarkdown-rendered links
+//    used to:
+//       - http/https → navigate canvas tab away (user lost canvas state)
+//       - workspace://path / file:///workspace/... / /workspace/... →
+//         browser hit about:blank (unhandled protocol).
+//    Fix: external links get target="_blank" + noopener; in-container
+//    paths route through downloadChatFile (same auth path as chips).
+
+import { describe, it, expect, vi, afterEach, beforeEach } from "vitest";
+import { render, screen, cleanup, fireEvent, waitFor } from "@testing-library/react";
+import React from "react";
+
+afterEach(cleanup);
+
+// Mock the api module so render doesn't try to talk to a real CP.
+const apiGet = vi.fn((_path: string): Promise<unknown> => Promise.resolve([]));
+const apiPost = vi.fn((_path: string, _body: unknown): Promise<unknown> => Promise.resolve({}));
+vi.mock("@/lib/api", () => ({
+  api: {
+    get: (path: string) => apiGet(path),
+    post: (path: string, body: unknown) => apiPost(path, body),
+    del: vi.fn(),
+    patch: vi.fn(),
+    put: vi.fn(),
+  },
+}));
+
+vi.mock("@/store/canvas", () => ({
+  useCanvasStore: vi.fn((selector?: (s: unknown) => unknown) =>
+    selector ? selector({ agentMessages: {}, consumeAgentMessages: () => [] }) : {},
+  ),
+}));
+
+// Capture the downloadChatFile call so the markdown-link test can
+// assert in-container paths route through the authenticated download
+// path rather than the browser's bare anchor click.
+const downloadChatFileMock = vi.fn((_workspaceId: string, _att: { uri: string; name: string }) => Promise.resolve());
+vi.mock("../chat/uploads", async () => {
+  const actual = await vi.importActual<typeof import("../chat/uploads")>("../chat/uploads");
+  return {
+    ...actual,
+    downloadChatFile: (workspaceId: string, att: { uri: string; name: string }) =>
+      downloadChatFileMock(workspaceId, att),
+  };
+});
+
+beforeEach(() => {
+  apiGet.mockClear();
+  apiPost.mockClear();
+  downloadChatFileMock.mockClear();
+  // jsdom doesn't implement scrollIntoView; ChatTab calls it after
+  // every render with a new message.
+  Element.prototype.scrollIntoView = vi.fn();
+  // Stub IntersectionObserver — the lazy-history sentinel uses it.
+  class FakeIO {
+    observe() {}
+    unobserve() {}
+    disconnect() {}
+  }
+  (window as unknown as { IntersectionObserver: unknown }).IntersectionObserver = FakeIO;
+  (globalThis as unknown as { IntersectionObserver: unknown }).IntersectionObserver = FakeIO;
+});
+
+import { ChatTab } from "../ChatTab";
+
+const minimalData = {
+  status: "online" as const,
+  runtime: "claude-code",
+  currentTask: null,
+} as unknown as Parameters<typeof ChatTab>[0]["data"];
+
+describe("ChatTab — IME-safe Enter key", () => {
+  it("does NOT send the message when Enter fires during IME composition (isComposing)", async () => {
+    render(<ChatTab workspaceId="ws-ime" data={minimalData} />);
+
+    // Find the textarea by its aria-label.
+    const textarea = await screen.findByLabelText(/Message to agent/i);
+    fireEvent.change(textarea, { target: { value: "你好" } });
+
+    // Simulate the Enter that commits an IME selection: isComposing=true.
+    fireEvent.keyDown(textarea, { key: "Enter", isComposing: true });
+
+    // sendMessage POSTs via api.post; assert it was NOT called.
+    await waitFor(() => {
+      expect(apiPost).not.toHaveBeenCalled();
+    });
+    // And the input is preserved — ChatTab clears it only on actual send.
+    expect((textarea as HTMLTextAreaElement).value).toBe("你好");
+  });
+
+  it("does NOT send when keyCode is 229 (older Safari IME fallback)", async () => {
+    render(<ChatTab workspaceId="ws-ime2" data={minimalData} />);
+    const textarea = await screen.findByLabelText(/Message to agent/i);
+    fireEvent.change(textarea, { target: { value: "한국어" } });
+
+    // keyCode 229 is the older-Safari signal that an IME is composing.
+    // Some mobile WebKit-based browsers delay setting isComposing on
+    // the composition-end Enter; the keyCode fallback covers that.
+    fireEvent.keyDown(textarea, { key: "Enter", keyCode: 229 });
+
+    await waitFor(() => {
+      expect(apiPost).not.toHaveBeenCalled();
+    });
+  });
+
+  it("DOES send on a non-composing Enter (the happy path stays intact)", async () => {
+    render(<ChatTab workspaceId="ws-ok" data={minimalData} />);
+    const textarea = await screen.findByLabelText(/Message to agent/i);
+    fireEvent.change(textarea, { target: { value: "hello world" } });
+
+    fireEvent.keyDown(textarea, { key: "Enter" /* no isComposing, no 229 */ });
+
+    // The api.post for /a2a fires inside sendMessage. waitFor since
+    // the call goes through several effects.
+    await waitFor(() => {
+      expect(apiPost).toHaveBeenCalled();
+    });
+  });
+
+  it("Shift+Enter inserts newline regardless (no send)", async () => {
+    render(<ChatTab workspaceId="ws-shift" data={minimalData} />);
+    const textarea = await screen.findByLabelText(/Message to agent/i);
+    fireEvent.change(textarea, { target: { value: "line 1" } });
+
+    fireEvent.keyDown(textarea, { key: "Enter", shiftKey: true });
+
+    await waitFor(() => {
+      expect(apiPost).not.toHaveBeenCalled();
+    });
+  });
+});
diff --git a/canvas/src/components/tabs/__tests__/MemoryTab.edit.test.tsx b/canvas/src/components/tabs/__tests__/MemoryTab.edit.test.tsx
deleted file mode 100644
index d20d8f28..00000000
--- a/canvas/src/components/tabs/__tests__/MemoryTab.edit.test.tsx
+++ /dev/null
@@ -1,220 +0,0 @@
-// @vitest-environment jsdom
-//
-// Pins the Edit affordance added to MemoryTab. Until this PR the Memory tab
-// was Add+Delete only; an entry that needed correction had to be deleted and
-// re-added — losing the version-counter and any in-flight optimistic-locking
-// invariants other writers depend on.
-//
-// Each test pins one branch of the new flow. If any fails, the bug is back.
-
-import { describe, it, expect, vi, afterEach, beforeEach } from "vitest";
-import { render, screen, cleanup, waitFor, fireEvent } from "@testing-library/react";
-import React from "react";
-
-afterEach(cleanup);
-
-const apiGet = vi.fn();
-const apiPost = vi.fn();
-const apiDel = vi.fn();
-vi.mock("@/lib/api", () => ({
-  api: {
-    get: (path: string) => apiGet(path),
-    post: (path: string, body: unknown) => apiPost(path, body),
-    del: (path: string) => apiDel(path),
-    patch: vi.fn(),
-    put: vi.fn(),
-  },
-}));
-
-import { MemoryTab } from "../MemoryTab";
-
-const sampleEntries = [
-  {
-    key: "team_brief",
-    value: { goal: "ship v2" },
-    version: 3,
-    expires_at: null,
-    updated_at: "2026-05-04T10:00:00Z",
-  },
-  {
-    key: "plain_note",
-    value: "raw text note",
-    version: 1,
-    expires_at: "2099-01-01T00:00:00Z",
-    updated_at: "2026-05-04T10:01:00Z",
-  },
-];
-
-beforeEach(() => {
-  apiGet.mockReset();
-  apiPost.mockReset();
-  apiDel.mockReset();
-  apiGet.mockImplementation((path: string) => {
-    if (path === "/workspaces/ws-test/memory") {
-      return Promise.resolve(sampleEntries);
-    }
-    return Promise.reject(new Error(`unmocked api.get: ${path}`));
-  });
-});
-
-async function renderAndExpand(key: string) {
-  render(<MemoryTab workspaceId="ws-test" />);
-  await waitFor(() => expect(apiGet).toHaveBeenCalled());
-  // Reveal the Advanced section that hosts the entry list.
-  const showAdvanced = await screen.findByRole("button", { name: "Show" });
-  fireEvent.click(showAdvanced);
-  // Expand the row.
-  const row = await screen.findByRole("button", { name: new RegExp(key) });
-  fireEvent.click(row);
-}
-
-describe("MemoryTab Edit affordance", () => {
-  it("Edit button appears once a row is expanded", async () => {
-    await renderAndExpand("team_brief");
-    expect(screen.getAllByRole("button", { name: "Edit" }).length).toBeGreaterThan(0);
-  });
-
-  it("clicking Edit on a JSON-valued entry pre-fills the textarea with pretty JSON", async () => {
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = (await screen.findByLabelText(
-      "Edit value for team_brief",
-    )) as HTMLTextAreaElement;
-    expect(textarea.value).toBe('{\n  "goal": "ship v2"\n}');
-  });
-
-  it("clicking Edit on a string-valued entry pre-fills raw (no surrounding quotes)", async () => {
-    await renderAndExpand("plain_note");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = (await screen.findByLabelText(
-      "Edit value for plain_note",
-    )) as HTMLTextAreaElement;
-    expect(textarea.value).toBe("raw text note");
-  });
-
-  it("Save POSTs with if_match_version + parsed value, then reloads", async () => {
-    apiPost.mockResolvedValue({ status: "ok", key: "team_brief", version: 4 });
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = await screen.findByLabelText("Edit value for team_brief");
-    fireEvent.change(textarea, { target: { value: '{"goal":"ship v3"}' } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    expect(apiPost).toHaveBeenCalledWith("/workspaces/ws-test/memory", {
-      key: "team_brief",
-      value: { goal: "ship v3" },
-      if_match_version: 3,
-    });
-    // Reload after save → second GET.
-    await waitFor(() => expect(apiGet).toHaveBeenCalledTimes(2));
-  });
-
-  it("Save with non-JSON text falls back to plain string", async () => {
-    apiPost.mockResolvedValue({ status: "ok" });
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = await screen.findByLabelText("Edit value for team_brief");
-    fireEvent.change(textarea, { target: { value: "free-form note" } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    expect(apiPost.mock.calls[0][1].value).toBe("free-form note");
-  });
-
-  it("TTL field is forwarded as ttl_seconds when set", async () => {
-    apiPost.mockResolvedValue({ status: "ok" });
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const ttlInput = await screen.findByLabelText("Edit TTL for team_brief");
-    fireEvent.change(ttlInput, { target: { value: "3600" } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    expect(apiPost.mock.calls[0][1].ttl_seconds).toBe(3600);
-  });
-
-  it("blank/zero/non-numeric TTL is omitted from the payload", async () => {
-    apiPost.mockResolvedValue({ status: "ok" });
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const ttlInput = await screen.findByLabelText("Edit TTL for team_brief");
-    // Junk + zero both must drop out — payload must not contain ttl_seconds.
-    fireEvent.change(ttlInput, { target: { value: "abc" } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    expect(apiPost.mock.calls[0][1]).not.toHaveProperty("ttl_seconds");
-  });
-
-  it("Cancel discards edits and restores the rendered value", async () => {
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = await screen.findByLabelText("Edit value for team_brief");
-    fireEvent.change(textarea, { target: { value: '{"goal":"discarded"}' } });
-    fireEvent.click(screen.getByRole("button", { name: "Cancel" }));
-
-    expect(apiPost).not.toHaveBeenCalled();
-    // Editor is gone; the JSON pre-block is back.
-    expect(screen.queryByLabelText("Edit value for team_brief")).toBeNull();
-    expect(screen.getAllByText(/"goal": "ship v2"/i).length).toBeGreaterThan(0);
-  });
-
-  it("409 response surfaces a retry hint and reloads", async () => {
-    apiPost.mockRejectedValueOnce(
-      new Error("HTTP 409: if_match_version mismatch"),
-    );
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = await screen.findByLabelText("Edit value for team_brief");
-    fireEvent.change(textarea, { target: { value: '{"goal":"ship v3"}' } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    const alert = await screen.findByRole("alert");
-    expect(alert.textContent).toMatch(/changed since you opened it/i);
-    // Initial mount load + post-conflict reload.
-    await waitFor(() => expect(apiGet).toHaveBeenCalledTimes(2));
-  });
-
-  it("non-409 error surfaces the message and does not reload", async () => {
-    apiPost.mockRejectedValueOnce(new Error("boom"));
-    await renderAndExpand("team_brief");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    const alert = await screen.findByRole("alert");
-    expect(alert.textContent).toBe("boom");
-    // Only the initial mount load — no retry reload.
-    expect(apiGet).toHaveBeenCalledTimes(1);
-  });
-
-  it("entry with no version omits if_match_version (back-compat with older shape)", async () => {
-    // Pre-version-counter shape: drop the `version` field from the row.
-    apiGet.mockReset();
-    apiGet.mockImplementation((path: string) => {
-      if (path === "/workspaces/ws-test/memory") {
-        return Promise.resolve([
-          {
-            key: "old_entry",
-            value: "legacy",
-            expires_at: null,
-            updated_at: "2026-05-04T10:00:00Z",
-          },
-        ]);
-      }
-      return Promise.reject(new Error(`unmocked: ${path}`));
-    });
-    apiPost.mockResolvedValue({ status: "ok" });
-
-    await renderAndExpand("old_entry");
-    fireEvent.click(screen.getAllByRole("button", { name: "Edit" })[0]);
-    const textarea = await screen.findByLabelText("Edit value for old_entry");
-    fireEvent.change(textarea, { target: { value: "updated" } });
-    fireEvent.click(screen.getByRole("button", { name: "Save" }));
-
-    await waitFor(() => expect(apiPost).toHaveBeenCalledTimes(1));
-    const payload = apiPost.mock.calls[0][1];
-    expect(payload).not.toHaveProperty("if_match_version");
-    expect(payload.value).toBe("updated");
-  });
-});
diff --git a/canvas/src/components/tabs/chat/uploads.ts b/canvas/src/components/tabs/chat/uploads.ts
index 04209dde..76fbdba9 100644
--- a/canvas/src/components/tabs/chat/uploads.ts
+++ b/canvas/src/components/tabs/chat/uploads.ts
@@ -44,6 +44,8 @@ export async function uploadChatFiles(
  *    - `workspace:<abs-path>` (our canonical form)
  *    - `file:///workspace/...` (some agents emit this)
  *    - `/workspace/...` (bare absolute path inside the container)
+ *    - `platform-pending:<wsid>/<file_id>` (poll-mode upload, staged
+ *      on platform side; resolves to /pending-uploads/<file_id>/content)
  *  Everything that looks like an allowed-root container path is
  *  rewritten to the authenticated /chat/download endpoint. HTTP(S)
  *  URIs pass through unchanged so we can also render links to
@@ -53,6 +55,35 @@ export function resolveAttachmentHref(
   workspaceId: string,
   uri: string,
 ): string {
+  // platform-pending: agents-emitted URI that lives in the platform-side
+  // staging layer (poll-mode chat uploads, see workspace-server's
+  // chat_files.go ~line 690 + pendinguploads.Storage). The wire shape
+  // is `platform-pending:<workspace_id>/<file_id>`. Resolving it
+  // requires hitting GET /workspaces/<wsid>/pending-uploads/<file_id>/content
+  // which streams the bytes with full workspace auth. Without this
+  // case the browser sees an unhandled-protocol click → about:blank,
+  // which was the user-visible bug from 2026-05-05 (reno-stars).
+  if (uri.startsWith("platform-pending:")) {
+    const rest = uri.slice("platform-pending:".length);
+    const slash = rest.indexOf("/");
+    // Defensive: if the URI doesn't have the expected wsid/fileid
+    // shape, fall through to raw-URI handling so the consumer can
+    // still try to render it (rather than producing a broken /pending-
+    // uploads/// path).
+    if (slash > 0) {
+      const wsid = rest.slice(0, slash);
+      const fileID = rest.slice(slash + 1);
+      if (wsid && fileID) {
+        // Use the URI's own workspace_id (the bytes live in THAT
+        // workspace's pending-uploads store), not the chat's
+        // workspace_id — these CAN differ when a user drags a file
+        // into one workspace's chat that gets forwarded to another
+        // (cross-workspace delegation, agent forwarding).
+        return `${PLATFORM_URL}/workspaces/${wsid}/pending-uploads/${fileID}/content`;
+      }
+    }
+    return uri;
+  }
   const containerPath = normalizeWorkspaceUri(uri);
   if (containerPath) {
     return `${PLATFORM_URL}/workspaces/${workspaceId}/chat/download?path=${encodeURIComponent(containerPath)}`;
@@ -60,6 +91,14 @@ export function resolveAttachmentHref(
   return uri;
 }
 
+/** Returns true when the URI points at a platform-side resource that
+ *  requires our auth headers — caller should route through
+ *  downloadChatFile rather than letting the browser navigate. */
+export function isPlatformAttachment(uri: string): boolean {
+  if (uri.startsWith("platform-pending:")) return true;
+  return normalizeWorkspaceUri(uri) !== null;
+}
+
 /** Extracts the absolute container path from a workspace-scoped URI,
  *  or null if the URI isn't a container path. The matching roots
  *  mirror the server's `allowedRoots` allowlist. */
@@ -96,8 +135,7 @@ export async function downloadChatFile(
   attachment: ChatAttachment,
 ): Promise<void> {
   const href = resolveAttachmentHref(workspaceId, attachment.uri);
-  const isContainerPath = normalizeWorkspaceUri(attachment.uri) !== null;
-  if (!isContainerPath) {
+  if (!isPlatformAttachment(attachment.uri)) {
     // External URL — let the browser navigate. Opens in new tab so
     // the canvas context survives a navigation. `href` here is the
     // raw URI (http(s), or anything else the agent sent back).
diff --git a/scripts/build_runtime_package.py b/scripts/build_runtime_package.py
index eb5e1daa..82b1090c 100755
--- a/scripts/build_runtime_package.py
+++ b/scripts/build_runtime_package.py
@@ -80,6 +80,7 @@ TOP_LEVEL_MODULES = {
     "internal_file_read",
     "main",
     "mcp_cli",
+    "mcp_doctor",
     "mcp_heartbeat",
     "mcp_inbox_pollers",
     "mcp_workspace_resolver",
diff --git a/workspace-server/internal/events/types.go b/workspace-server/internal/events/types.go
new file mode 100644
index 00000000..a081d46e
--- /dev/null
+++ b/workspace-server/internal/events/types.go
@@ -0,0 +1,125 @@
+package events
+
+// types.go — typed taxonomy of WebSocket event names emitted by the
+// workspace-server.
+//
+// RFC #2945 PR-B. Pre-consolidation, every BroadcastOnly /
+// RecordAndBroadcast call site passed a bare string literal:
+//
+//	h.broadcaster.BroadcastOnly(workspaceID, "AGENT_MESSAGE", payload)
+//
+// Producers (Go workspace-server, ~30 call sites across handlers/,
+// scheduler/, registry/, bundle/) and consumers (canvas TS store +
+// component listeners) duplicated the same string with no shared
+// definition. A producer renaming an event silently broke every
+// consumer — same drift class that produced the reno-stars data-loss
+// regression on the persistence side. The fix on that side was the
+// AgentMessageWriter SSOT (PR-A); the fix on this side is named
+// constants.
+//
+// Why a typed string (not a plain enum / iota): the event name
+// crosses the wire to TypeScript consumers as the literal string in
+// `WSMessage.Event`. Iota integers would break the canvas store's
+// switch (`case "AGENT_MESSAGE":`); a typed string preserves the
+// wire contract while giving Go callers compile-time discipline.
+//
+// Mirror in canvas: a parity gate (PR-B-2 follow-up) will assert this
+// constant set ≡ the TypeScript union members in
+// `canvas/src/lib/ws-events.ts`. Today the canvas consumes the names
+// via bare-string comparisons; the mirror lands separately to keep
+// PR-B narrow.
+
+// EventType is the wire-typed name of a WebSocket event the platform
+// broadcasts. Always emit constants from this file rather than bare
+// strings — the AST gate in events_types_drift_test.go guards
+// against bare-string usage in the broadcaster surfaces.
+type EventType string
+
+// Event constants — the canonical taxonomy. New events MUST be added
+// here AND mirrored in canvas/src/lib/ws-events.ts (parity gate
+// pending in PR-B-2). Group by semantic family so the list stays
+// scan-friendly as it grows.
+const (
+	// Chat / agent messaging — surfaces in canvas chat panels.
+	EventAgentMessage EventType = "AGENT_MESSAGE"
+	EventA2AResponse  EventType = "A2A_RESPONSE"
+	EventActivityLogged EventType = "ACTIVITY_LOGGED"
+	EventChannelMessage EventType = "CHANNEL_MESSAGE"
+
+	// Workspace lifecycle.
+	EventWorkspaceProvisioning    EventType = "WORKSPACE_PROVISIONING"
+	EventWorkspaceProvisionFailed EventType = "WORKSPACE_PROVISION_FAILED"
+	EventWorkspaceOnline          EventType = "WORKSPACE_ONLINE"
+	EventWorkspaceOffline         EventType = "WORKSPACE_OFFLINE"
+	EventWorkspaceDegraded        EventType = "WORKSPACE_DEGRADED"
+	EventWorkspaceHibernated      EventType = "WORKSPACE_HIBERNATED"
+	EventWorkspacePaused          EventType = "WORKSPACE_PAUSED"
+	EventWorkspaceRemoved         EventType = "WORKSPACE_REMOVED"
+	EventWorkspaceAwaitingAgent   EventType = "WORKSPACE_AWAITING_AGENT"
+	EventWorkspaceHeartbeat       EventType = "WORKSPACE_HEARTBEAT"
+
+	// Agent assignment + identity.
+	EventAgentAssigned     EventType = "AGENT_ASSIGNED"
+	EventAgentReplaced     EventType = "AGENT_REPLACED"
+	EventAgentRemoved      EventType = "AGENT_REMOVED"
+	EventAgentMoved        EventType = "AGENT_MOVED"
+	EventAgentCardUpdated  EventType = "AGENT_CARD_UPDATED"
+
+	// Delegation lifecycle.
+	EventDelegationSent     EventType = "DELEGATION_SENT"
+	EventDelegationStatus   EventType = "DELEGATION_STATUS"
+	EventDelegationComplete EventType = "DELEGATION_COMPLETE"
+	EventDelegationFailed   EventType = "DELEGATION_FAILED"
+
+	// Task progression + scheduler.
+	EventTaskUpdated EventType = "TASK_UPDATED"
+	EventCronExecuted EventType = "CRON_EXECUTED"
+	EventCronSkipped  EventType = "CRON_SKIPPED"
+
+	// Approvals.
+	EventApprovalRequested EventType = "APPROVAL_REQUESTED"
+	EventApprovalEscalated EventType = "APPROVAL_ESCALATED"
+
+	// Auth / credentials.
+	EventExternalCredentialsRotated EventType = "EXTERNAL_CREDENTIALS_ROTATED"
+)
+
+// AllEventTypes lists every constant in this file. Used by the
+// snapshot test (events_types_drift_test.go) to detect when a new
+// constant is added without updating the snapshot — the catch-up
+// step is mirroring the addition into canvas/src/lib/ws-events.ts so
+// canvas consumers can switch on it.
+//
+// Keep in lexicographic order so the snapshot diff is stable on
+// renames and the parity-with-TS comparison is order-independent.
+var AllEventTypes = []EventType{
+	EventA2AResponse,
+	EventActivityLogged,
+	EventAgentAssigned,
+	EventAgentCardUpdated,
+	EventAgentMessage,
+	EventAgentMoved,
+	EventAgentRemoved,
+	EventAgentReplaced,
+	EventApprovalEscalated,
+	EventApprovalRequested,
+	EventChannelMessage,
+	EventCronExecuted,
+	EventCronSkipped,
+	EventDelegationComplete,
+	EventDelegationFailed,
+	EventDelegationSent,
+	EventDelegationStatus,
+	EventExternalCredentialsRotated,
+	EventTaskUpdated,
+	EventWorkspaceAwaitingAgent,
+	EventWorkspaceDegraded,
+	EventWorkspaceHeartbeat,
+	EventWorkspaceHibernated,
+	EventWorkspaceOffline,
+	EventWorkspaceOnline,
+	EventWorkspacePaused,
+	EventWorkspaceProvisionFailed,
+	EventWorkspaceProvisioning,
+	EventWorkspaceRemoved,
+}
diff --git a/workspace-server/internal/events/types_test.go b/workspace-server/internal/events/types_test.go
new file mode 100644
index 00000000..a16e2e8b
--- /dev/null
+++ b/workspace-server/internal/events/types_test.go
@@ -0,0 +1,117 @@
+package events
+
+import (
+	"sort"
+	"strings"
+	"testing"
+)
+
+// TestAllEventTypes_IsSnapshot pins the canonical event taxonomy.
+// Adding a new constant in types.go without updating AllEventTypes
+// (or vice versa) fails this test.
+//
+// The snapshot is also the authoritative input to the canvas-side
+// parity gate (PR-B-2 follow-up): the TypeScript union members in
+// canvas/src/lib/ws-events.ts MUST match this list exactly. A drift
+// gate at CI time will assert set equality once the TS file lands.
+func TestAllEventTypes_IsSnapshot(t *testing.T) {
+	// Every named constant must appear in AllEventTypes. Walk via
+	// reflection over the package-level vars would over-include test
+	// fixtures, so list the canonical names here. When a constant
+	// is added in types.go, append the EventType's literal value
+	// to the expected list below — the failure message names
+	// exactly what's missing so the diff is one-line obvious.
+	expected := []string{
+		"A2A_RESPONSE",
+		"ACTIVITY_LOGGED",
+		"AGENT_ASSIGNED",
+		"AGENT_CARD_UPDATED",
+		"AGENT_MESSAGE",
+		"AGENT_MOVED",
+		"AGENT_REMOVED",
+		"AGENT_REPLACED",
+		"APPROVAL_ESCALATED",
+		"APPROVAL_REQUESTED",
+		"CHANNEL_MESSAGE",
+		"CRON_EXECUTED",
+		"CRON_SKIPPED",
+		"DELEGATION_COMPLETE",
+		"DELEGATION_FAILED",
+		"DELEGATION_SENT",
+		"DELEGATION_STATUS",
+		"EXTERNAL_CREDENTIALS_ROTATED",
+		"TASK_UPDATED",
+		"WORKSPACE_AWAITING_AGENT",
+		"WORKSPACE_DEGRADED",
+		"WORKSPACE_HEARTBEAT",
+		"WORKSPACE_HIBERNATED",
+		"WORKSPACE_OFFLINE",
+		"WORKSPACE_ONLINE",
+		"WORKSPACE_PAUSED",
+		"WORKSPACE_PROVISIONING",
+		"WORKSPACE_PROVISION_FAILED",
+		"WORKSPACE_REMOVED",
+	}
+	sort.Strings(expected)
+
+	actual := make([]string, 0, len(AllEventTypes))
+	for _, e := range AllEventTypes {
+		actual = append(actual, string(e))
+	}
+	sort.Strings(actual)
+
+	if len(actual) != len(expected) {
+		t.Errorf("AllEventTypes count = %d, want %d\nactual:   %s\nexpected: %s",
+			len(actual), len(expected),
+			strings.Join(actual, ", "),
+			strings.Join(expected, ", "))
+		return
+	}
+	for i, want := range expected {
+		if actual[i] != want {
+			t.Errorf("AllEventTypes[%d] = %q, want %q (full diff:\n  actual:   %v\n  expected: %v\n)",
+				i, actual[i], want, actual, expected)
+		}
+	}
+}
+
+// TestEventType_NoEmptyConstants pins that no constant declared in
+// types.go has an accidentally-empty value. The catch is the
+// "WORKSPACE_X" → forgot-to-fill pattern: a typo in the literal
+// would surface as the empty string, and broadcast pipelines would
+// silently filter empty-name events without any error signal.
+func TestEventType_NoEmptyConstants(t *testing.T) {
+	for _, e := range AllEventTypes {
+		if string(e) == "" {
+			t.Errorf("found empty EventType in AllEventTypes — typo in types.go?")
+		}
+	}
+}
+
+// TestEventType_AllUppercaseSnakeCase pins the wire format. Mixed
+// case or kebab-case would break the canvas TypeScript switch
+// statements (every consumer's `case "AGENT_MESSAGE":` is upper-
+// snake). The check is the catch for an accidental
+// `"agent_message"` typo that wouldn't fail the snapshot gate.
+func TestEventType_AllUppercaseSnakeCase(t *testing.T) {
+	for _, e := range AllEventTypes {
+		s := string(e)
+		// Allowed chars: A-Z, 0-9, _ — nothing else, no leading/
+		// trailing underscores, no consecutive underscores.
+		if s != strings.ToUpper(s) {
+			t.Errorf("EventType %q is not all-uppercase — wire format requires upper-snake", s)
+		}
+		if strings.HasPrefix(s, "_") || strings.HasSuffix(s, "_") {
+			t.Errorf("EventType %q has leading/trailing underscore — disallowed", s)
+		}
+		if strings.Contains(s, "__") {
+			t.Errorf("EventType %q has consecutive underscores — disallowed", s)
+		}
+		for _, r := range s {
+			if !((r >= 'A' && r <= 'Z') || (r >= '0' && r <= '9') || r == '_') {
+				t.Errorf("EventType %q contains disallowed char %q", s, r)
+				break
+			}
+		}
+	}
+}
diff --git a/workspace-server/internal/handlers/activity.go b/workspace-server/internal/handlers/activity.go
index 7c90ff52..db63b155 100644
--- a/workspace-server/internal/handlers/activity.go
+++ b/workspace-server/internal/handlers/activity.go
@@ -465,78 +465,30 @@ func (h *ActivityHandler) Notify(c *gin.Context) {
 		}
 	}
 
-	// Verify workspace exists
-	var wsName string
-	err := db.DB.QueryRowContext(c.Request.Context(),
-		`SELECT name FROM workspaces WHERE id = $1 AND status != 'removed'`, workspaceID,
-	).Scan(&wsName)
-	if err != nil {
-		c.JSON(http.StatusNotFound, gin.H{"error": "workspace not found"})
-		return
+	// Single source of truth for chat-bearing agent → user messages —
+	// see agent_message_writer.go for the contract. Pre-RFC-#2945, the
+	// broadcast + INSERT pair was inlined here and again in
+	// mcp_tools.go's send_message_to_user, and the duplication is what
+	// produced the reno-stars data-loss regression. Both paths now
+	// route through the same writer; future channels (Slack, Discord,
+	// Lark) hook in here too.
+	attachments := make([]AgentMessageAttachment, 0, len(body.Attachments))
+	for _, a := range body.Attachments {
+		attachments = append(attachments, AgentMessageAttachment{
+			URI:      a.URI,
+			Name:     a.Name,
+			MimeType: a.MimeType,
+			Size:     a.Size,
+		})
 	}
-
-	broadcastPayload := map[string]interface{}{
-		"message":      body.Message,
-		"workspace_id": workspaceID,
-		"name":         wsName,
-	}
-	if len(body.Attachments) > 0 {
-		broadcastPayload["attachments"] = body.Attachments
-	}
-	h.broadcaster.BroadcastOnly(workspaceID, "AGENT_MESSAGE", broadcastPayload)
-
-	// Persist to activity_logs so the chat history loader restores this
-	// message after a page reload. Pre-fix, send_message_to_user pushes
-	// were broadcast-only — survived the WebSocket session but vanished
-	// when the user refreshed because nothing wrote them to the DB.
-	//
-	// Shape chosen to match the existing loader query
-	// (`type=a2a_receive&source=canvas`):
-	//   - activity_type='a2a_receive' so it joins the same query path
-	//   - source_id=NULL so the canvas-source filter accepts it
-	//   - method='notify' to distinguish from real A2A receives in audits
-	//   - request_body=NULL so the loader doesn't append a duplicate
-	//     "user message" bubble for it
-	//   - response_body={"result": "<text>"} matches extractResponseText's
-	//     simplest branch ({result: string} → take verbatim)
-	//
-	// Errors are logged-only — broadcast already succeeded, the user
-	// sees the message; persistence failure just means the message
-	// won't survive reload (pre-fix behavior). Don't fail the whole
-	// notify on a DB hiccup.
-	// response_body shape — chosen to feed BOTH:
-	//   - extractResponseText: looks at body.result (string) and returns it
-	//   - extractFilesFromTask: looks at body.parts[] for kind=file
-	// so a chat reload after a notify-with-attachments restores both
-	// the text bubble AND the download chips.
-	respPayload := map[string]interface{}{"result": body.Message}
-	if len(body.Attachments) > 0 {
-		fileParts := make([]map[string]interface{}, 0, len(body.Attachments))
-		for _, a := range body.Attachments {
-			fileMeta := map[string]interface{}{"uri": a.URI, "name": a.Name}
-			if a.MimeType != "" {
-				fileMeta["mimeType"] = a.MimeType
-			}
-			if a.Size > 0 {
-				fileMeta["size"] = a.Size
-			}
-			fileParts = append(fileParts, map[string]interface{}{
-				"kind": "file",
-				"file": fileMeta,
-			})
+	writer := NewAgentMessageWriter(db.DB, h.broadcaster)
+	if err := writer.Send(c.Request.Context(), workspaceID, body.Message, attachments); err != nil {
+		if errors.Is(err, ErrWorkspaceNotFound) {
+			c.JSON(http.StatusNotFound, gin.H{"error": "workspace not found"})
+			return
 		}
-		respPayload["parts"] = fileParts
-	}
-	respJSON, _ := json.Marshal(respPayload)
-	preview := body.Message
-	if len(preview) > 80 {
-		preview = preview[:80] + "…"
-	}
-	if _, err := db.DB.ExecContext(c.Request.Context(), `
-		INSERT INTO activity_logs (workspace_id, activity_type, method, summary, response_body, status)
-		VALUES ($1, 'a2a_receive', 'notify', $2, $3::jsonb, 'ok')
-	`, workspaceID, "Agent message: "+preview, string(respJSON)); err != nil {
-		log.Printf("Notify: failed to persist message for %s: %v", workspaceID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "internal error"})
+		return
 	}
 
 	c.JSON(http.StatusOK, gin.H{"status": "sent"})
diff --git a/workspace-server/internal/handlers/agent_message_writer.go b/workspace-server/internal/handlers/agent_message_writer.go
new file mode 100644
index 00000000..dbbce3e7
--- /dev/null
+++ b/workspace-server/internal/handlers/agent_message_writer.go
@@ -0,0 +1,203 @@
+package handlers
+
+// AgentMessageWriter is the SSOT for "agent → user" message delivery in the
+// workspace-server. Every chat-bearing path that surfaces a message to the
+// canvas — HTTP /notify (Notify handler), MCP tools/call
+// send_message_to_user (toolSendMessageToUser), any future channel — MUST
+// route through this writer rather than re-implement the broadcast +
+// persist contract inline.
+//
+// Why: pre-consolidation, two handlers duplicated the same "broadcast then
+// INSERT activity_logs" sequence. The reno-stars production data-loss
+// incident (2026-05-05, RFC #2945, PR #2944) was the symptom — the
+// persistence half landed for /notify but lagged for the MCP bridge by
+// months, silently dropping every long-form external-agent message until
+// reload. The AST gate from #2944 catches drift; this writer eliminates
+// the *possibility* of drift by giving both call sites a single
+// well-tested function to call.
+//
+// Contract:
+//   1. Look up the workspace by id; ErrWorkspaceNotFound on miss so the
+//      caller can return 404 with a clean message.
+//   2. Broadcast a WS AGENT_MESSAGE event with {message, workspace_id,
+//      name, attachments?}.
+//   3. INSERT a row into activity_logs:
+//        type='a2a_receive', method='notify', source_id NULL,
+//        response_body={"result": message[, "parts": [file kind...]]},
+//        status='ok'
+//      Best-effort — INSERT failure logs only, returns nil so the broadcast
+//      success isn't undone on the caller side.
+//   4. Returns nil on success.
+//
+// The shape (especially the JSON response_body) is the wire contract the
+// canvas's chat-history hydrator (canvas/src/.../historyHydration.ts)
+// reads. Drift here silently breaks chat replay across all consumers, so
+// changes to the JSON shape MUST be cross-verified against the hydrator
+// in the same PR.
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"log"
+	"unicode/utf8"
+
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/events"
+)
+
+// ErrWorkspaceNotFound is returned by AgentMessageWriter.Send when the
+// workspace lookup turns up nothing (or the workspace is in
+// status='removed'). Callers translate to HTTP 404 / JSON-RPC error /
+// whatever surface they expose. Real DB errors (connection drop, query
+// timeout) surface as wrapped errors and should be treated as 503.
+var ErrWorkspaceNotFound = errors.New("agent_message: workspace not found")
+
+// truncatePreviewRunes returns at most maxRunes runes of s, plus an ellipsis
+// when truncated. Operates on the rune (codepoint) boundary instead of
+// byte indices — the previous byte-slice version produced invalid UTF-8
+// when maxRunes landed mid-codepoint (CJK, emoji, accented characters
+// in agent-authored chat messages), and Postgres JSONB rejects invalid
+// UTF-8, dropping the activity_log INSERT silently. The persistence
+// failure log fires but the message vanishes from chat history — the
+// exact regression class the SSOT consolidation was built to prevent.
+//
+// maxRunes is in runes, not bytes — `truncatePreviewRunes("你好", 1)` returns
+// `"你…"`, not `"\xe4…"`. Set the cap on a UI-friendly basis (visible
+// character count, not stored byte count); 80 runes covers the
+// activity_logs.summary column comfortably.
+func truncatePreviewRunes(s string, maxRunes int) string {
+	if utf8.RuneCountInString(s) <= maxRunes {
+		return s
+	}
+	// Walk runes until we've consumed maxRunes; cut at that byte index.
+	count := 0
+	cut := len(s)
+	for i := range s {
+		if count == maxRunes {
+			cut = i
+			break
+		}
+		count++
+	}
+	return s[:cut] + "…"
+}
+
+// AgentMessageAttachment is one file attached to an agent → user
+// message. Identical to handlers.NotifyAttachment in field set; kept
+// distinct so the writer's API doesn't import a handler type with HTTP
+// binding tags.
+type AgentMessageAttachment struct {
+	URI      string
+	Name     string
+	MimeType string
+	Size     int64
+}
+
+// AgentMessageWriter persists + broadcasts agent → user messages. Construct
+// once per process via NewAgentMessageWriter; pass the same instance to
+// every handler that delivers chat (Notify, toolSendMessageToUser, etc.).
+//
+// Takes events.EventEmitter (not the *Broadcaster concrete type) so tests
+// can substitute a fake emitter and producers in other packages can wrap
+// the real broadcaster behind their own metrics / retries without leaking
+// the concrete dependency.
+type AgentMessageWriter struct {
+	db          *sql.DB
+	broadcaster events.EventEmitter
+}
+
+// NewAgentMessageWriter binds the writer to the platform's DB pool +
+// WebSocket broadcaster.
+func NewAgentMessageWriter(db *sql.DB, broadcaster events.EventEmitter) *AgentMessageWriter {
+	return &AgentMessageWriter{db: db, broadcaster: broadcaster}
+}
+
+// Send delivers a single agent → user message. Look up + broadcast +
+// persist in that order; ErrWorkspaceNotFound short-circuits before any
+// broadcast or DB write so callers can 404 cleanly.
+//
+// Returns nil on success — including on DB-INSERT failure (the broadcast
+// already returned successfully and the user has seen the message; the
+// persistence-failure mode is logged at WARN but the caller's response
+// stays 200 so the agent doesn't retry and double-broadcast).
+func (w *AgentMessageWriter) Send(
+	ctx context.Context,
+	workspaceID, message string,
+	attachments []AgentMessageAttachment,
+) error {
+	// 1. Workspace lookup. status='removed' filter is the same shape /notify
+	//    used pre-consolidation; deleted workspaces don't get notifications.
+	//
+	// Distinguish sql.ErrNoRows ("workspace genuinely not present" — caller
+	// should 404) from real DB errors (connection drop, statement timeout,
+	// pool exhaustion — caller should 503). Pre-fix this branch returned
+	// ErrWorkspaceNotFound for any error, so during a DB outage every
+	// notify call surfaced as "workspace not found" and masked real
+	// incidents in the alert path.
+	var wsName string
+	err := w.db.QueryRowContext(ctx,
+		`SELECT name FROM workspaces WHERE id = $1 AND status != 'removed'`,
+		workspaceID,
+	).Scan(&wsName)
+	if errors.Is(err, sql.ErrNoRows) {
+		return ErrWorkspaceNotFound
+	}
+	if err != nil {
+		return fmt.Errorf("agent_message: workspace lookup: %w", err)
+	}
+
+	// 2. Build broadcast payload + WS-emit. Same shape that ChatTab's
+	//    AGENT_MESSAGE handler in canvas/src/store/canvas-events.ts has
+	//    consumed since the canvas chat shipped — drift here would orphan
+	//    every live chat panel.
+	broadcastPayload := map[string]interface{}{
+		"message":      message,
+		"workspace_id": workspaceID,
+		"name":         wsName,
+	}
+	if len(attachments) > 0 {
+		broadcastPayload["attachments"] = attachments
+	}
+	w.broadcaster.BroadcastOnly(workspaceID, string(events.EventAgentMessage), broadcastPayload)
+
+	// 3. Persist for chat-history hydration. response_body shape MUST stay
+	//    in sync with extractResponseText + extractFilesFromTask in
+	//    canvas/src/components/tabs/chat/historyHydration.ts:
+	//      - extractResponseText reads body.result (string) → renders text
+	//      - extractFilesFromTask reads body.parts[] (kind=file) → renders chips
+	respPayload := map[string]interface{}{"result": message}
+	if len(attachments) > 0 {
+		fileParts := make([]map[string]interface{}, 0, len(attachments))
+		for _, a := range attachments {
+			fileMeta := map[string]interface{}{"uri": a.URI, "name": a.Name}
+			if a.MimeType != "" {
+				fileMeta["mimeType"] = a.MimeType
+			}
+			if a.Size > 0 {
+				fileMeta["size"] = a.Size
+			}
+			fileParts = append(fileParts, map[string]interface{}{
+				"kind": "file",
+				"file": fileMeta,
+			})
+		}
+		respPayload["parts"] = fileParts
+	}
+	respJSON, _ := json.Marshal(respPayload)
+	preview := truncatePreviewRunes(message, 80)
+	if _, err := w.db.ExecContext(ctx, `
+		INSERT INTO activity_logs (workspace_id, activity_type, method, summary, response_body, status)
+		VALUES ($1, 'a2a_receive', 'notify', $2, $3::jsonb, 'ok')
+	`, workspaceID, "Agent message: "+preview, string(respJSON)); err != nil {
+		// Best-effort: the broadcast already returned ok and the user
+		// has seen the message. Logging a structured line lets operators
+		// notice persistence-failure rates spike if the DB is unhealthy,
+		// without breaking the tool response or causing the agent to
+		// retry-and-double-broadcast.
+		log.Printf("agent_message: failed to persist for %s: %v", workspaceID, err)
+	}
+
+	return nil
+}
diff --git a/workspace-server/internal/handlers/agent_message_writer_test.go b/workspace-server/internal/handlers/agent_message_writer_test.go
new file mode 100644
index 00000000..880d2273
--- /dev/null
+++ b/workspace-server/internal/handlers/agent_message_writer_test.go
@@ -0,0 +1,448 @@
+package handlers
+
+import (
+	"context"
+	"database/sql/driver"
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+	"unicode/utf8"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/db"
+)
+
+// AgentMessageWriter is the SSOT for agent → user chat delivery
+// (RFC #2945 PR-A). These tests pin the contract the writer
+// guarantees: workspace lookup, broadcast, INSERT, error semantics —
+// every shape that producers (Notify, toolSendMessageToUser, future
+// channels) rely on.
+//
+// Pre-consolidation, the broadcast-then-INSERT logic was duplicated
+// across two handlers and they drifted (reno-stars, 2026-05-05). With
+// the writer being the only place this logic lives, these tests are
+// the regression line for every chat-bearing path simultaneously.
+
+// jsonMatcher is a sqlmock Argument matcher that decodes the actual
+// SQL arg as JSON and runs a caller-supplied predicate over the
+// resulting structure. Tighter than substring matching (which can
+// false-pass on a renamed key) and tolerant of map-key ordering
+// (which exact-string matching is not).
+type jsonMatcher struct {
+	predicate func(parsed map[string]any) bool
+	desc      string
+}
+
+func (m jsonMatcher) Match(v driver.Value) bool {
+	s, ok := v.(string)
+	if !ok {
+		return false
+	}
+	var parsed map[string]any
+	if err := json.Unmarshal([]byte(s), &parsed); err != nil {
+		return false
+	}
+	return m.predicate(parsed)
+}
+
+// stringMatcher pins exact prefix/suffix/equality checks against a
+// driver.Value that's actually a string.
+type stringMatcher func(string) bool
+
+func (f stringMatcher) Match(v driver.Value) bool {
+	s, ok := v.(string)
+	if !ok {
+		return false
+	}
+	return f(s)
+}
+
+// capturingEmitter records every BroadcastOnly call so tests can pin
+// the WS event shape without a real ws.Hub. RecordAndBroadcast is
+// also captured for completeness — the writer doesn't call it today,
+// but a future producer might, and a captured-but-unasserted record
+// is easier to diagnose than a nil panic.
+type capturingEmitter struct {
+	events []capturedEvent
+}
+
+type capturedEvent struct {
+	workspaceID string
+	eventType   string
+	payload     interface{}
+}
+
+func (c *capturingEmitter) BroadcastOnly(workspaceID string, eventType string, payload interface{}) {
+	c.events = append(c.events, capturedEvent{workspaceID, eventType, payload})
+}
+
+func (c *capturingEmitter) RecordAndBroadcast(_ context.Context, eventType string, workspaceID string, payload interface{}) error {
+	c.events = append(c.events, capturedEvent{workspaceID, eventType, payload})
+	return nil
+}
+
+// TestAgentMessageWriter_Send_Success_NoAttachments pins the happy
+// path: workspace lookup, broadcast, INSERT, return nil.
+func TestAgentMessageWriter_Send_Success_NoAttachments(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-1").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("CEO Ryan PC"))
+
+	mock.ExpectExec(`INSERT INTO activity_logs.*'a2a_receive'.*'notify'`).
+		WithArgs(
+			"ws-1",
+			sqlmock.AnyArg(), // summary
+			`{"result":"hi"}`,
+		).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	if err := w.Send(context.Background(), "ws-1", "hi", nil); err != nil {
+		t.Fatalf("Send returned %v, want nil", err)
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("DB expectations: %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_Success_WithAttachments pins the file
+// attachment shape — response_body MUST contain a parts[] array with
+// kind=file entries so the canvas hydrater renders download chips.
+// Drift here = chips disappear on chat reload.
+func TestAgentMessageWriter_Send_Success_WithAttachments(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-att").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("Ryan"))
+
+	mock.ExpectExec(`INSERT INTO activity_logs.*'a2a_receive'.*'notify'`).
+		WithArgs(
+			"ws-att",
+			sqlmock.AnyArg(),
+			jsonMatcher{
+				desc: "response_body has result + parts with kind=file metadata",
+				predicate: func(p map[string]any) bool {
+					if p["result"] != "see attached" {
+						return false
+					}
+					parts, ok := p["parts"].([]any)
+					if !ok || len(parts) != 1 {
+						return false
+					}
+					part, ok := parts[0].(map[string]any)
+					if !ok {
+						return false
+					}
+					if part["kind"] != "file" {
+						return false
+					}
+					file, ok := part["file"].(map[string]any)
+					if !ok {
+						return false
+					}
+					return file["uri"] == "workspace://x.zip" &&
+						file["name"] == "x.zip" &&
+						file["mimeType"] == "application/zip" &&
+						file["size"].(float64) == 1234
+				},
+			},
+		).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	atts := []AgentMessageAttachment{
+		{URI: "workspace://x.zip", Name: "x.zip", MimeType: "application/zip", Size: 1234},
+	}
+	if err := w.Send(context.Background(), "ws-att", "see attached", atts); err != nil {
+		t.Fatalf("Send returned %v, want nil", err)
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("DB expectations: %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_WorkspaceNotFound pins ErrWorkspaceNotFound
+// short-circuit. Must NOT broadcast, MUST NOT INSERT — caller will 404
+// or surface a JSON-RPC error.
+func TestAgentMessageWriter_Send_WorkspaceNotFound(t *testing.T) {
+	mock := setupTestDB(t)
+	emitter := &capturingEmitter{}
+	w := NewAgentMessageWriter(db.DB, emitter)
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-missing").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}))
+
+	err := w.Send(context.Background(), "ws-missing", "lost in the void", nil)
+	if !errors.Is(err, ErrWorkspaceNotFound) {
+		t.Errorf("Send returned %v, want ErrWorkspaceNotFound", err)
+	}
+	if len(emitter.events) != 0 {
+		t.Errorf("workspace-not-found path MUST NOT broadcast, got %d events", len(emitter.events))
+	}
+	// Implicit: no INSERT expectation registered, so a stray INSERT
+	// would fail ExpectationsWereMet.
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("DB expectations (INSERT must NOT fire on workspace-not-found): %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_DBInsertFailureStillReturnsNil pins the
+// "best-effort persistence" contract: when the activity_log INSERT
+// fails (DB hiccup, transient connection, constraint), the writer
+// MUST still return nil. The broadcast already succeeded; the user
+// has seen the message; returning an error here would cause the
+// caller (and the agent calling the tool) to retry and double-
+// broadcast.
+func TestAgentMessageWriter_Send_DBInsertFailureStillReturnsNil(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-dbfail").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("CEO Ryan PC"))
+
+	mock.ExpectExec(`INSERT INTO activity_logs`).
+		WillReturnError(errors.New("transient db error"))
+
+	err := w.Send(context.Background(), "ws-dbfail", "should not be lost from live chat", nil)
+	if err != nil {
+		t.Errorf("DB INSERT failure must return nil (broadcast already succeeded), got %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_PreviewTruncation pins the summary
+// preview cap. Long messages (Ryan's onboarding-friction report was
+// ~2k chars) must summarise to ≤80 chars + ellipsis so the activity
+// table doesn't carry multi-KB summaries that bloat list queries.
+func TestAgentMessageWriter_Send_PreviewTruncation(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-trunc").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("Ryan"))
+
+	longMsg := strings.Repeat("x", 200)
+	mock.ExpectExec(`INSERT INTO activity_logs`).
+		WithArgs(
+			"ws-trunc",
+			stringMatcher(func(s string) bool {
+				if !strings.HasPrefix(s, "Agent message: ") {
+					return false
+				}
+				preview := strings.TrimPrefix(s, "Agent message: ")
+				if !strings.HasSuffix(preview, "…") {
+					return false
+				}
+				body := strings.TrimSuffix(preview, "…")
+				return len(body) == 80
+			}),
+			sqlmock.AnyArg(),
+		).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	if err := w.Send(context.Background(), "ws-trunc", longMsg, nil); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("preview truncation drift: %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_BroadcastsAgentMessageEvent pins the
+// WS event name + payload shape. The canvas's
+// canvas-events.ts:AGENT_MESSAGE handler reads {message, workspace_id,
+// name, attachments?} — drift here orphans every live chat panel.
+func TestAgentMessageWriter_Send_BroadcastsAgentMessageEvent(t *testing.T) {
+	mock := setupTestDB(t)
+	emitter := &capturingEmitter{}
+	w := NewAgentMessageWriter(db.DB, emitter)
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-bc").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("Workspace Name"))
+	mock.ExpectExec(`INSERT INTO activity_logs`).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	atts := []AgentMessageAttachment{
+		{URI: "workspace://a.txt", Name: "a.txt"},
+	}
+	if err := w.Send(context.Background(), "ws-bc", "hi", atts); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+
+	if len(emitter.events) != 1 {
+		t.Fatalf("expected exactly 1 broadcast, got %d", len(emitter.events))
+	}
+	ev := emitter.events[0]
+	if ev.eventType != "AGENT_MESSAGE" {
+		t.Errorf("event type = %q, want AGENT_MESSAGE", ev.eventType)
+	}
+	if ev.workspaceID != "ws-bc" {
+		t.Errorf("workspace_id = %q, want ws-bc", ev.workspaceID)
+	}
+	pl, ok := ev.payload.(map[string]interface{})
+	if !ok {
+		t.Fatalf("payload not a map: %T", ev.payload)
+	}
+	if pl["message"] != "hi" {
+		t.Errorf("payload.message = %v, want hi", pl["message"])
+	}
+	if pl["workspace_id"] != "ws-bc" {
+		t.Errorf("payload.workspace_id = %v, want ws-bc", pl["workspace_id"])
+	}
+	if pl["name"] != "Workspace Name" {
+		t.Errorf("payload.name = %v, want Workspace Name", pl["name"])
+	}
+	if pl["attachments"] == nil {
+		t.Error("payload.attachments missing on attachment-bearing send")
+	}
+}
+
+// TestAgentMessageWriter_Send_DBErrorOnLookupReturnsWrapped pins the
+// distinction between sql.ErrNoRows (legit not-found → 404) and real
+// DB errors (connection drop → 503). Pre-followup the lookup branch
+// returned ErrWorkspaceNotFound for ANY error, so during a DB outage
+// every notify call surfaced as "workspace not found" and masked
+// real incidents in alerting.
+func TestAgentMessageWriter_Send_DBErrorOnLookupReturnsWrapped(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	transientErr := errors.New("connection refused")
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-dbdown").
+		WillReturnError(transientErr)
+
+	err := w.Send(context.Background(), "ws-dbdown", "hi", nil)
+	if err == nil {
+		t.Fatal("expected wrapped DB error, got nil")
+	}
+	if errors.Is(err, ErrWorkspaceNotFound) {
+		t.Errorf("DB outage MUST NOT surface as ErrWorkspaceNotFound (masks incidents in alerting); got %v", err)
+	}
+	if !errors.Is(err, transientErr) {
+		t.Errorf("expected wrapped %v, got %v", transientErr, err)
+	}
+}
+
+// TestTruncatePreviewRunes_RuneBoundary pins the multi-byte-safe
+// truncation. The previous byte-slice version produced invalid UTF-8
+// when the cut landed mid-codepoint (CJK, emoji, accented), and
+// Postgres JSONB rejects invalid UTF-8 — INSERT fails, log.Printf
+// fires, message vanishes from chat history. Per memory
+// feedback_assert_exact_not_substring.md, pin the boundary cases
+// directly.
+func TestTruncatePreviewRunes_RuneBoundary(t *testing.T) {
+	cases := []struct {
+		name     string
+		in       string
+		max      int
+		want     string
+	}{
+		{"under-max ASCII", "hi", 80, "hi"},
+		{"under-max CJK", "你好", 80, "你好"},
+		{"exactly-at-max", "abcde", 5, "abcde"},
+		{"truncate ASCII", "abcdefghij", 5, "abcde…"},
+		{"truncate CJK at rune boundary", "你好世界你好世界", 4, "你好世界…"},
+		{"truncate emoji at rune boundary", "😀😀😀😀😀😀", 3, "😀😀😀…"},
+		// The pre-fix bug shape: byte-slice on non-ASCII would have
+		// mangled the codepoint here. With rune-boundary truncation
+		// the result is well-formed UTF-8.
+		{"non-zero with emoji prefix", "🚀abcdefghijk", 5, "🚀abcd…"},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			got := truncatePreviewRunes(c.in, c.max)
+			if got != c.want {
+				t.Errorf("truncatePreviewRunes(%q, %d) = %q, want %q", c.in, c.max, got, c.want)
+			}
+			// Always-valid UTF-8 invariant. A byte-slice truncation
+			// could leave partial codepoints; this version must not.
+			if !utf8.ValidString(got) {
+				t.Errorf("truncatePreviewRunes(%q, %d) returned invalid UTF-8: %q", c.in, c.max, got)
+			}
+		})
+	}
+}
+
+// TestAgentMessageWriter_Send_NonASCIIMessagePersists pins the end-to-end
+// path for non-ASCII messages — the original reno-stars regression
+// surfaced via byte-slice truncation breaking JSONB INSERT. Every
+// handler-level test had ASCII content, so this branch had no
+// coverage. Now it does.
+func TestAgentMessageWriter_Send_NonASCIIMessagePersists(t *testing.T) {
+	mock := setupTestDB(t)
+	w := NewAgentMessageWriter(db.DB, newTestBroadcaster())
+
+	// 200-rune CJK message — exceeds the 80-rune cap, would have hit
+	// the byte-slice bug.
+	msg := strings.Repeat("你", 200)
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-cjk").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("CEO Ryan PC"))
+
+	mock.ExpectExec(`INSERT INTO activity_logs`).
+		WithArgs(
+			"ws-cjk",
+			stringMatcher(func(s string) bool {
+				if !strings.HasPrefix(s, "Agent message: ") {
+					return false
+				}
+				preview := strings.TrimPrefix(s, "Agent message: ")
+				if !strings.HasSuffix(preview, "…") {
+					return false
+				}
+				body := strings.TrimSuffix(preview, "…")
+				// 80 runes of 你 = 80 codepoints. Each is 3 bytes UTF-8.
+				if utf8.RuneCountInString(body) != 80 {
+					return false
+				}
+				// MUST be valid UTF-8 — pre-fix byte-slice would have
+				// returned half a codepoint here.
+				return utf8.ValidString(body)
+			}),
+			sqlmock.AnyArg(),
+		).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	if err := w.Send(context.Background(), "ws-cjk", msg, nil); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("non-ASCII path drift: %v", err)
+	}
+}
+
+// TestAgentMessageWriter_Send_OmitsAttachmentsKeyWhenEmpty pins the
+// "no key when nil" wire contract — extra empty fields would force
+// canvas consumers to defensively check for [] vs undefined; the
+// existing AGENT_MESSAGE handler treats absence as "no attachments".
+func TestAgentMessageWriter_Send_OmitsAttachmentsKeyWhenEmpty(t *testing.T) {
+	mock := setupTestDB(t)
+	emitter := &capturingEmitter{}
+	w := NewAgentMessageWriter(db.DB, emitter)
+
+	mock.ExpectQuery("SELECT name FROM workspaces").
+		WithArgs("ws-noatt").
+		WillReturnRows(sqlmock.NewRows([]string{"name"}).AddRow("X"))
+	mock.ExpectExec(`INSERT INTO activity_logs`).
+		WillReturnResult(sqlmock.NewResult(1, 1))
+
+	if err := w.Send(context.Background(), "ws-noatt", "plain text", nil); err != nil {
+		t.Fatalf("Send: %v", err)
+	}
+	if len(emitter.events) != 1 {
+		t.Fatalf("expected 1 event, got %d", len(emitter.events))
+	}
+	pl := emitter.events[0].payload.(map[string]interface{})
+	if _, present := pl["attachments"]; present {
+		t.Errorf("attachments key MUST NOT be present when empty (canvas treats absence as 'none'); payload=%v", pl)
+	}
+}
diff --git a/workspace-server/internal/handlers/delegation_ledger.go b/workspace-server/internal/handlers/delegation_ledger.go
index 9a783ece..621cdbd9 100644
--- a/workspace-server/internal/handlers/delegation_ledger.go
+++ b/workspace-server/internal/handlers/delegation_ledger.go
@@ -53,13 +53,35 @@ func NewDelegationLedger(handle *sql.DB) *DelegationLedger {
 // truncatePreview caps stored preview at 4KB. The full prompt/response is
 // already in activity_logs.{request,response}_body — this is the at-a-glance
 // view for the dashboard, not a forensic record.
+//
+// Rune-safe: previous byte-slice form (s[:previewCap]) split on a byte
+// boundary, which on a multi-byte codepoint at byte 4096 produced
+// invalid UTF-8 — Postgres JSONB rejects → ledger row not inserted →
+// audit gap. Issue #2962. Walks the string by rune, stops at the last
+// rune-boundary index that fits inside the cap. ASCII-only strings hit
+// the cap exactly; CJK/emoji strings stop slightly under the cap,
+// never over.
+//
+// Mirrors the truncatePreviewRunes fix from agent_message_writer.go
+// (#2959). Both call sites should consume a shared helper after both
+// fixes have landed — followup deduplication tracked in #2962's body.
 const previewCap = 4096
 
 func truncatePreview(s string) string {
 	if len(s) <= previewCap {
 		return s
 	}
-	return s[:previewCap]
+	// Range over a string yields rune-boundary byte indices. Walk
+	// until the next index would exceed previewCap; the previous
+	// index is the safe truncation point.
+	end := 0
+	for i := range s {
+		if i > previewCap {
+			break
+		}
+		end = i
+	}
+	return s[:end]
 }
 
 // InsertOpts is the agent's record-of-intent. Caller, callee, task preview,
diff --git a/workspace-server/internal/handlers/delegation_ledger_test.go b/workspace-server/internal/handlers/delegation_ledger_test.go
index 78cb4b94..48f1a3cd 100644
--- a/workspace-server/internal/handlers/delegation_ledger_test.go
+++ b/workspace-server/internal/handlers/delegation_ledger_test.go
@@ -5,6 +5,7 @@ import (
 	"errors"
 	"strings"
 	"testing"
+	"unicode/utf8"
 
 	"github.com/DATA-DOG/go-sqlmock"
 )
@@ -121,6 +122,63 @@ func TestTruncatePreview_ExactlyAtCap(t *testing.T) {
 	}
 }
 
+// TestTruncatePreview_NeverProducesInvalidUTF8 — pins #2962. The old
+// byte-slice implementation (s[:previewCap]) split on a byte boundary,
+// so a multi-byte codepoint straddling byte 4096 produced invalid
+// UTF-8 → Postgres JSONB rejects → ledger row not inserted → audit
+// gap. Test feeds a CJK / emoji-padded string longer than previewCap
+// and asserts utf8.ValidString on the result.
+func TestTruncatePreview_NeverProducesInvalidUTF8(t *testing.T) {
+	// Build a string of '世' (3 bytes per rune in UTF-8) that's just
+	// past the cap. With the old implementation, the slice at byte
+	// previewCap would land mid-rune and ValidString would fail.
+	// With the rune-aware implementation, the result is always valid
+	// UTF-8 even if the byte length is < previewCap.
+	rune3 := "世" // U+4E16, 3 bytes
+	// Need at least previewCap/3 + 1 runes so we cross the cap with
+	// margin to spare.
+	in := strings.Repeat(rune3, (previewCap/3)+10)
+	if len(in) <= previewCap {
+		t.Fatalf("test setup: input too short (%d bytes) — must exceed previewCap=%d", len(in), previewCap)
+	}
+	got := truncatePreview(in)
+	if !utf8.ValidString(got) {
+		t.Errorf("truncatePreview produced invalid UTF-8 — JSONB will reject this row. len(got)=%d", len(got))
+	}
+	if len(got) > previewCap {
+		t.Errorf("truncatePreview exceeded cap: len(got)=%d > previewCap=%d", len(got), previewCap)
+	}
+	// Defense-in-depth: the result should also be a clean rune
+	// prefix of the input — not some garbled sequence.
+	if !strings.HasPrefix(in, got) {
+		t.Errorf("truncatePreview should return a prefix of the input")
+	}
+}
+
+// TestTruncatePreview_MultiByteAtBoundary — most-targeted regression.
+// Feeds an input where the cap byte falls EXACTLY in the middle of a
+// 3-byte codepoint. Pre-fix, this is the case that produces invalid
+// UTF-8; post-fix, the truncate stops at the previous rune boundary.
+func TestTruncatePreview_MultiByteAtBoundary(t *testing.T) {
+	// Build a string that's `previewCap-1` ASCII bytes followed by
+	// '世' (3 bytes). Total = previewCap + 2. The old impl would
+	// slice at byte previewCap, landing inside the '世' codepoint.
+	prefix := strings.Repeat("a", previewCap-1)
+	in := prefix + "世"
+	if len(in) != previewCap+2 {
+		t.Fatalf("test setup: expected len %d, got %d", previewCap+2, len(in))
+	}
+	got := truncatePreview(in)
+	if !utf8.ValidString(got) {
+		t.Errorf("truncatePreview produced invalid UTF-8 at the multi-byte boundary case")
+	}
+	// Result should be exactly the ASCII prefix — '世' was past
+	// the cap so it must be dropped entirely.
+	if got != prefix {
+		t.Errorf("expected exact ASCII prefix, got %q (len=%d)", got[len(got)-10:], len(got))
+	}
+}
+
 // ---------- SetStatus lifecycle ----------
 
 func TestLedgerSetStatus_QueuedToDispatched(t *testing.T) {
diff --git a/workspace-server/internal/handlers/external_connection.go b/workspace-server/internal/handlers/external_connection.go
index 4730d36b..320e761e 100644
--- a/workspace-server/internal/handlers/external_connection.go
+++ b/workspace-server/internal/handlers/external_connection.go
@@ -423,14 +423,23 @@ mkdir -p ~/.codex
 # (then open ~/.codex/config.toml in your editor and paste:)
 #
 # [mcp_servers.molecule]
-# command = "python3"
-# args = ["-m", "molecule_runtime.a2a_mcp_server"]
+# command = "molecule-mcp"
+# args = []
 # startup_timeout_sec = 30
 #
 # [mcp_servers.molecule.env]
 # WORKSPACE_ID = "{{WORKSPACE_ID}}"
 # PLATFORM_URL = "{{PLATFORM_URL}}"
 # MOLECULE_WORKSPACE_TOKEN = "<paste from create response>"
+#
+# Use the "molecule-mcp" console-script wrapper (NOT
+# "python3 -m molecule_runtime.a2a_mcp_server"). The wrapper is what
+# keeps the workspace ALIVE on the canvas: it POSTs /registry/register
+# at startup and runs a 20s heartbeat thread alongside the MCP stdio
+# loop. The bare a2a_mcp_server module exposes tools but does NOT
+# heartbeat — pointing codex at it leaves the canvas showing this
+# workspace as awaiting_agent (OFFLINE) within 60-90s even while
+# tools work.
 
 # 3. Run the bridge daemon as a durable background process — this
 #    is the INBOUND path. Long-polls the platform inbox and runs
@@ -507,11 +516,20 @@ pip install molecule-ai-workspace-runtime
 
 # 3. Wire the molecule MCP server. {{WORKSPACE_ID}} + {{PLATFORM_URL}}
 # are stamped server-side; paste the auth token before running.
+#
+# Use the "molecule-mcp" console-script wrapper (NOT
+# "python3 -m molecule_runtime.a2a_mcp_server"). The wrapper is what
+# keeps the workspace ALIVE on the canvas: it POSTs /registry/register
+# at startup and runs a 20s heartbeat thread alongside the MCP stdio
+# loop. The bare a2a_mcp_server module exposes tools but does NOT
+# heartbeat — pointing openclaw at it leaves the canvas showing this
+# workspace as awaiting_agent (OFFLINE) within 60-90s even while
+# tools work.
 WORKSPACE_TOKEN="<paste from create response>"
 openclaw mcp set molecule "$(cat <<EOF
 {
-  "command": "python3",
-  "args": ["-m", "molecule_runtime.a2a_mcp_server"],
+  "command": "molecule-mcp",
+  "args": [],
   "env": {
     "WORKSPACE_ID": "{{WORKSPACE_ID}}",
     "PLATFORM_URL": "{{PLATFORM_URL}}",
diff --git a/workspace-server/internal/handlers/external_connection_test.go b/workspace-server/internal/handlers/external_connection_test.go
index 8ec725ee..cd843693 100644
--- a/workspace-server/internal/handlers/external_connection_test.go
+++ b/workspace-server/internal/handlers/external_connection_test.go
@@ -38,3 +38,40 @@ func TestExternalTemplates_NoMoleculeOrgIDPlaceholder(t *testing.T) {
 		}
 	}
 }
+
+// TestExternalMcpTemplates_UseMoleculeMcpWrapper pins the invariant
+// that operator-facing snippets configuring an MCP server entry point
+// use the ``molecule-mcp`` console-script wrapper (mcp_cli.main),
+// NOT the bare ``a2a_mcp_server`` module.
+//
+// Why: a2a_mcp_server exposes the MCP tools but does NOT call
+// /registry/register or run the 20s heartbeat thread. mcp_cli wraps
+// it with both, which is what flips the canvas presence indicator
+// from awaiting_agent (OFFLINE) to online and keeps it that way.
+// Originally tracked by molecule-core#2957 — operator hit the
+// silent-OFFLINE failure mode when the Codex tab pointed at the bare
+// module.
+//
+// The hermes-channel template intentionally uses the bare module: it
+// owns the platform plugin path and runs its own
+// register_platform/heartbeat code in-process, so wrapping with
+// mcp_cli would double-heartbeat. universalMcp / codex / openclaw
+// must all use the wrapper.
+func TestExternalMcpTemplates_UseMoleculeMcpWrapper(t *testing.T) {
+	mustUseWrapper := map[string]string{
+		"externalUniversalMcpTemplate": externalUniversalMcpTemplate,
+		"externalCodexTemplate":        externalCodexTemplate,
+		"externalOpenClawTemplate":     externalOpenClawTemplate,
+	}
+	for name, body := range mustUseWrapper {
+		if !strings.Contains(body, "molecule-mcp") {
+			t.Errorf("%s does not reference 'molecule-mcp' — operator-facing MCP snippets must point at the heartbeat-wrapping console script, not the bare a2a_mcp_server module (#2957)", name)
+		}
+		if strings.Contains(body, `"-m", "molecule_runtime.a2a_mcp_server"`) {
+			t.Errorf("%s spawns 'python3 -m molecule_runtime.a2a_mcp_server' — that bypasses the standalone register/heartbeat wrapper, leaving the canvas showing the workspace OFFLINE (#2957). Use 'molecule-mcp' instead.", name)
+		}
+		if strings.Contains(body, `["-m", "molecule_runtime.a2a_mcp_server"]`) {
+			t.Errorf("%s spawns 'python3 -m molecule_runtime.a2a_mcp_server' — that bypasses the standalone register/heartbeat wrapper, leaving the canvas showing the workspace OFFLINE (#2957). Use 'molecule-mcp' instead.", name)
+		}
+	}
+}
diff --git a/workspace-server/internal/handlers/mcp_tools.go b/workspace-server/internal/handlers/mcp_tools.go
index 961921de..dfb93e48 100644
--- a/workspace-server/internal/handlers/mcp_tools.go
+++ b/workspace-server/internal/handlers/mcp_tools.go
@@ -11,6 +11,7 @@ import (
 	"context"
 	"database/sql"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"log"
@@ -330,57 +331,23 @@ func (h *MCPHandler) toolSendMessageToUser(ctx context.Context, workspaceID stri
 		return "", fmt.Errorf("send_message_to_user is not enabled on this MCP bridge (set MOLECULE_MCP_ALLOW_SEND_MESSAGE=true)")
 	}
 
-	var wsName string
-	err := h.database.QueryRowContext(ctx,
-		`SELECT name FROM workspaces WHERE id = $1 AND status != 'removed'`, workspaceID,
-	).Scan(&wsName)
-	if err != nil {
-		return "", fmt.Errorf("workspace not found")
-	}
-
-	h.broadcaster.BroadcastOnly(workspaceID, "AGENT_MESSAGE", map[string]interface{}{
-		"message":      message,
-		"workspace_id": workspaceID,
-		"name":         wsName,
-	})
-
-	// Persist to activity_logs so chat history loaders surface this
-	// message after a page reload. Pre-fix (reno-stars 2026-05-05),
-	// the MCP-bridge variant of send_message_to_user broadcast WS
-	// only — visible live, gone on reload — while the HTTP /notify
-	// sibling already had this fix (activity.go:535). External
-	// claude-code agents using molecule-mcp's send_message_to_user
-	// tool route through THIS handler, not /notify, so they were
-	// hitting the unfixed path.
+	// Single source of truth for chat-bearing agent → user messages —
+	// see agent_message_writer.go for the contract. The pre-RFC-#2945
+	// duplication of broadcast + INSERT logic between this handler and
+	// activity.go:Notify is what produced the reno-stars data-loss
+	// regression; both paths now route through the same writer.
 	//
-	// Shape mirrors activity.go's Notify handler exactly so the
-	// canvas chat-history hydration treats both the same:
-	//   - activity_type='a2a_receive' joins the source=canvas filter
-	//   - source_id is omitted → defaults to NULL ("canvas-source")
-	//   - method='notify' tags it as a push (vs a real A2A receive)
-	//   - request_body=NULL so the loader doesn't draw a duplicate
-	//     "user" bubble
-	//   - response_body={"result": "<text>"} feeds extractResponseText
-	//     directly
-	//
-	// Errors are log-only — the broadcast already returned ok to the
-	// caller, the user has seen the message, and the persistence
-	// failure mode (DB hiccup) shouldn't block the tool call. The
-	// downside is the same as pre-fix: message vanishes on reload
-	// after a transient DB error. Log it so operators have a signal.
-	respPayload := map[string]interface{}{"result": message}
-	respJSON, _ := json.Marshal(respPayload)
-	preview := message
-	if len(preview) > 80 {
-		preview = preview[:80] + "…"
+	// MCP send_message_to_user does not currently surface attachments
+	// (the tool args don't accept them); pass nil. If a future tool
+	// schema adds an attachments arg, build []AgentMessageAttachment
+	// and pass through.
+	writer := NewAgentMessageWriter(h.database, h.broadcaster)
+	if err := writer.Send(ctx, workspaceID, message, nil); err != nil {
+		if errors.Is(err, ErrWorkspaceNotFound) {
+			return "", fmt.Errorf("workspace not found")
+		}
+		return "", err
 	}
-	if _, err := h.database.ExecContext(ctx, `
-		INSERT INTO activity_logs (workspace_id, activity_type, method, summary, response_body, status)
-		VALUES ($1, 'a2a_receive', 'notify', $2, $3::jsonb, 'ok')
-	`, workspaceID, "Agent message: "+preview, string(respJSON)); err != nil {
-		log.Printf("MCP send_message_to_user: failed to persist for %s: %v", workspaceID, err)
-	}
-
 	return "Message sent.", nil
 }
 
diff --git a/workspace-server/internal/handlers/memories_v2.go b/workspace-server/internal/handlers/memories_v2.go
new file mode 100644
index 00000000..91b48642
--- /dev/null
+++ b/workspace-server/internal/handlers/memories_v2.go
@@ -0,0 +1,416 @@
+package handlers
+
+// memories_v2.go — HTTP endpoints that expose Memory v2 plugin state to
+// the canvas Memory tab. Reads-only; writes still go through the MCP
+// path (see mcp_tools_memory_v2.go) where SAFE-T1201 redaction +
+// org-write audit happen at a single funnel.
+//
+// Why a separate v2 endpoint set rather than retrofitting memories.go:
+//
+//   - memories.go reads `agent_memories` (legacy v1 table). After the
+//     2026-05-05 cutover, agent commits go to the plugin's
+//     memory_records — agent_memories is frozen. The canvas Memory
+//     tab reading memories.go shows STALE data.
+//   - The plugin is loopback-only on each tenant (127.0.0.1:9100), so
+//     the canvas (browser) cannot call it directly. workspace-server
+//     proxies through these endpoints.
+//   - v2 has different shape (namespace tree, kind/source/pin/TTL,
+//     score) — overloading memories.go would break v1 consumers
+//     (admin export, the back-compat MCP shim).
+//
+// All endpoints sit under the same wsAuth group memories.go uses,
+// so the existing per-tenant token gates them automatically.
+
+import (
+	"errors"
+	"log"
+	"net/http"
+	"strconv"
+	"time"
+
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/memory/client"
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/memory/contract"
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/memory/namespace"
+	"github.com/gin-gonic/gin"
+)
+
+// MemoriesV2Handler bundles the plugin client + namespace resolver
+// behind a slim HTTP surface. Construction matches the rest of the
+// handlers package: NewMemoriesV2Handler followed by WithMemoryV2 (or
+// the test-only withMemoryV2APIs) at boot.
+type MemoriesV2Handler struct {
+	plugin   memoryPluginAPI
+	resolver namespaceResolverAPI
+}
+
+// NewMemoriesV2Handler constructs an unwired handler. Every method
+// returns 503 until WithMemoryV2 is called — keeps a partial deploy
+// (MEMORY_PLUGIN_URL absent) from crashing the canvas with 500s.
+func NewMemoriesV2Handler() *MemoriesV2Handler {
+	return &MemoriesV2Handler{}
+}
+
+// WithMemoryV2 attaches the live plugin client + resolver. Returns
+// the receiver for fluent boot-time wiring, mirroring MCPHandler.
+func (h *MemoriesV2Handler) WithMemoryV2(plugin *client.Client, resolver *namespace.Resolver) *MemoriesV2Handler {
+	h.plugin = plugin
+	h.resolver = resolver
+	return h
+}
+
+// withMemoryV2APIs is the test-only injection path: takes the
+// interfaces directly so unit tests don't have to construct a real
+// *client.Client / namespace.Resolver. Keep symmetric with
+// MCPHandler.withMemoryV2APIs so handler tests can re-use the same
+// stubs.
+func (h *MemoriesV2Handler) withMemoryV2APIs(plugin memoryPluginAPI, resolver namespaceResolverAPI) *MemoriesV2Handler {
+	h.plugin = plugin
+	h.resolver = resolver
+	return h
+}
+
+// available reports whether the v2 deps are wired. Each route checks
+// this and returns 503 + a clear hint when the plugin isn't
+// configured, matching the MCP-side error.
+func (h *MemoriesV2Handler) available() error {
+	if h == nil || h.plugin == nil || h.resolver == nil {
+		return errors.New("memory plugin is not configured (set MEMORY_PLUGIN_URL)")
+	}
+	return nil
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// GET /workspaces/:id/v2/namespaces
+//
+// Returns the namespace tree the canvas uses to drive the Memory tab's
+// namespace dropdown. Two arrays:
+//
+//   - readable[]: every namespace this workspace can READ from. Drives
+//     the "show me memories from X" filter dropdown.
+//   - writable[]: subset of readable that this workspace can WRITE to.
+//     Used for future canvas-side commit (not in this PR but the
+//     contract is symmetric so the dropdown can disable read-only
+//     entries when wiring up commit).
+//
+// Each entry carries name + kind + a friendly label so the canvas
+// doesn't have to parse `workspace:abc-123` itself. Kind ranks the
+// dropdown grouping (workspace → team → org → custom).
+// ─────────────────────────────────────────────────────────────────────────────
+
+// NamespaceView is the UI-friendly DTO returned by GET v2/namespaces.
+// Internal namespace.Namespace has fields the canvas doesn't need
+// (resolver-internal flags, raw metadata blobs); this strips it down.
+type NamespaceView struct {
+	Name string                 `json:"name"`
+	Kind contract.NamespaceKind `json:"kind"`
+	// Label is a stable display string the canvas can render directly.
+	// For workspace:<id> it's "Workspace (<short-id>)"; for team:<id>
+	// it's "Team (<short-id>)"; org/custom carry the raw suffix.
+	Label string `json:"label"`
+}
+
+// NamespacesResponse is the body of GET v2/namespaces.
+type NamespacesResponse struct {
+	Readable []NamespaceView `json:"readable"`
+	Writable []NamespaceView `json:"writable"`
+}
+
+// Namespaces handles GET /workspaces/:id/v2/namespaces.
+func (h *MemoriesV2Handler) Namespaces(c *gin.Context) {
+	if err := h.available(); err != nil {
+		c.JSON(http.StatusServiceUnavailable, gin.H{"error": err.Error()})
+		return
+	}
+	workspaceID := c.Param("id")
+	ctx := c.Request.Context()
+
+	readable, err := h.resolver.ReadableNamespaces(ctx, workspaceID)
+	if err != nil {
+		log.Printf("v2/namespaces readable error workspace=%s: %v", workspaceID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to resolve readable namespaces"})
+		return
+	}
+	writable, err := h.resolver.WritableNamespaces(ctx, workspaceID)
+	if err != nil {
+		log.Printf("v2/namespaces writable error workspace=%s: %v", workspaceID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to resolve writable namespaces"})
+		return
+	}
+
+	c.JSON(http.StatusOK, NamespacesResponse{
+		Readable: namespacesToViews(readable),
+		Writable: namespacesToViews(writable),
+	})
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// GET /workspaces/:id/v2/memories
+//
+// Search the plugin for memories visible to this workspace.
+//
+// Query params (all optional):
+//   - namespace: a single readable namespace to scope to. Omitted ⇒ all
+//     readable namespaces (dropdown's "All" mode).
+//   - q: full-text query string. Empty ⇒ recency-ordered listing.
+//   - kind: one of fact|summary|checkpoint. Empty ⇒ all kinds.
+//   - limit: max rows. Defaults to 50, clamped to 100. Matches the
+//     v1 endpoint's clamp shape (memories.go:memoryRecallMaxLimit).
+//
+// Server-side ACL invariant: the request is ALWAYS intersected with
+// the resolver's readable set on the server. A canvas-supplied
+// `namespace=foo:bar` that this workspace can't read returns an empty
+// list, NOT 403 — the canvas dropdown is built from /v2/namespaces
+// so a forbidden value is a stale-cache bug, not malice. Existence
+// non-inference: empty result is indistinguishable from "you can't
+// read this namespace" — same as the wsAuth-protected v1 endpoints.
+// ─────────────────────────────────────────────────────────────────────────────
+
+const memoriesV2DefaultLimit = 50
+const memoriesV2MaxLimit = 100
+
+// Search handles GET /workspaces/:id/v2/memories.
+func (h *MemoriesV2Handler) Search(c *gin.Context) {
+	if err := h.available(); err != nil {
+		c.JSON(http.StatusServiceUnavailable, gin.H{"error": err.Error()})
+		return
+	}
+	workspaceID := c.Param("id")
+	ctx := c.Request.Context()
+
+	requestedNS := c.Query("namespace")
+	query := c.Query("q")
+	kindStr := c.Query("kind")
+	limit := parseLimit(c.Query("limit"))
+
+	// Resolve the readable set, then intersect the request.
+	// IntersectReadable handles both the empty-request case (return
+	// all readable) and the explicit-namespace case (return [ns] iff
+	// readable, else []).
+	var requested []string
+	if requestedNS != "" {
+		requested = []string{requestedNS}
+	}
+	scopedNamespaces, err := h.resolver.IntersectReadable(ctx, workspaceID, requested)
+	if err != nil {
+		log.Printf("v2/memories intersect error workspace=%s: %v", workspaceID, err)
+		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to resolve namespaces"})
+		return
+	}
+	// Empty after intersection — caller asked for a namespace they
+	// can't read, OR they have no readable namespaces at all. Return
+	// [] (not 404) so the canvas can render its empty-state without
+	// special-casing.
+	if len(scopedNamespaces) == 0 {
+		c.JSON(http.StatusOK, MemoriesResponse{Memories: []MemoryView{}})
+		return
+	}
+
+	req := contract.SearchRequest{
+		Namespaces: scopedNamespaces,
+		Query:      query,
+		Limit:      limit,
+	}
+	if kindStr != "" {
+		req.Kinds = []contract.MemoryKind{contract.MemoryKind(kindStr)}
+	}
+
+	resp, err := h.plugin.Search(ctx, req)
+	if err != nil {
+		log.Printf("v2/memories plugin error workspace=%s: %v", workspaceID, err)
+		c.JSON(http.StatusBadGateway, gin.H{"error": "memory plugin search failed"})
+		return
+	}
+
+	out := MemoriesResponse{Memories: make([]MemoryView, 0, len(resp.Memories))}
+	for _, m := range resp.Memories {
+		out.Memories = append(out.Memories, memoryToView(m))
+	}
+	c.JSON(http.StatusOK, out)
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// DELETE /workspaces/:id/v2/memories/:memoryId
+//
+// Forget a memory. The plugin enforces its own ownership model — we
+// pass `requested_by_namespace = workspace:<id>` so the audit trail
+// records who initiated the forget; the plugin's ACL gate decides
+// whether the deletion is allowed.
+//
+// 404 (not 403) on a missing or non-owned memory: existence-non-
+// inferring response, matches the v1 DELETE in memories.go.
+// ─────────────────────────────────────────────────────────────────────────────
+
+// Forget handles DELETE /workspaces/:id/v2/memories/:memoryId.
+func (h *MemoriesV2Handler) Forget(c *gin.Context) {
+	if err := h.available(); err != nil {
+		c.JSON(http.StatusServiceUnavailable, gin.H{"error": err.Error()})
+		return
+	}
+	workspaceID := c.Param("id")
+	memoryID := c.Param("memoryId")
+	ctx := c.Request.Context()
+
+	if memoryID == "" {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "memoryId is required"})
+		return
+	}
+
+	body := contract.ForgetRequest{
+		RequestedByNamespace: "workspace:" + workspaceID,
+	}
+	if err := h.plugin.ForgetMemory(ctx, memoryID, body); err != nil {
+		// Map plugin not_found → 404. Anything else is upstream error.
+		var ce *contract.Error
+		if errors.As(err, &ce) && ce.Code == contract.ErrorCodeNotFound {
+			c.JSON(http.StatusNotFound, gin.H{"error": "memory not found"})
+			return
+		}
+		log.Printf("v2/memories forget error workspace=%s memory=%s: %v", workspaceID, memoryID, err)
+		c.JSON(http.StatusBadGateway, gin.H{"error": "memory plugin delete failed"})
+		return
+	}
+	c.JSON(http.StatusOK, gin.H{"status": "deleted"})
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// View shaping helpers
+// ─────────────────────────────────────────────────────────────────────────────
+
+// MemoryView is the canvas-facing shape of a v2 memory record. The raw
+// contract.Memory carries internal fields we don't expose (raw
+// `propagation` blob); MemoryView strips it to what the Memory tab
+// renders.
+type MemoryView struct {
+	ID        string                 `json:"id"`
+	Namespace string                 `json:"namespace"`
+	Content   string                 `json:"content"`
+	Kind      contract.MemoryKind    `json:"kind"`
+	Source    contract.MemorySource  `json:"source"`
+	Pin       bool                   `json:"pin"`
+	ExpiresAt *time.Time             `json:"expires_at,omitempty"`
+	CreatedAt time.Time              `json:"created_at"`
+	// Score is the plugin's similarity score (1.0 = exact); only
+	// populated when ?q= is set and the plugin supports embedding.
+	Score *float64 `json:"score,omitempty"`
+	// SourceWorkspaceID is parsed out of `propagation.source_workspace_id`
+	// when present (cross-workspace propagation) — lets the canvas
+	// render a "from <peer>" badge so users can tell their own writes
+	// apart from team-shared memory.
+	SourceWorkspaceID string `json:"source_workspace_id,omitempty"`
+}
+
+// MemoriesResponse is the body of GET v2/memories.
+type MemoriesResponse struct {
+	Memories []MemoryView `json:"memories"`
+}
+
+func memoryToView(m contract.Memory) MemoryView {
+	v := MemoryView{
+		ID:        m.ID,
+		Namespace: m.Namespace,
+		Content:   m.Content,
+		Kind:      m.Kind,
+		Source:    m.Source,
+		Pin:       m.Pin,
+		ExpiresAt: m.ExpiresAt,
+		CreatedAt: m.CreatedAt,
+		Score:     m.Score,
+	}
+	if m.Propagation != nil {
+		// `source_workspace_id` is a propagation contract field
+		// (RFC #2728 §5). Plugin emits it on writes that originated
+		// from a different workspace. Best-effort string extraction —
+		// don't fail rendering if shape drifts.
+		if raw, ok := m.Propagation["source_workspace_id"]; ok {
+			if s, ok := raw.(string); ok && s != "" {
+				v.SourceWorkspaceID = s
+			}
+		}
+	}
+	return v
+}
+
+// namespacesToViews converts resolver namespaces into UI-friendly
+// views. Stable sort: workspace → team → org → custom, then by name.
+func namespacesToViews(in []namespace.Namespace) []NamespaceView {
+	views := make([]NamespaceView, 0, len(in))
+	for _, n := range in {
+		views = append(views, NamespaceView{
+			Name:  n.Name,
+			Kind:  n.Kind,
+			Label: namespaceLabel(n.Name, n.Kind),
+		})
+	}
+	return views
+}
+
+// namespaceLabel renders a human-friendly label for a namespace. The
+// canvas displays this directly; we keep the formatting server-side
+// so the shape stays consistent across UIs (canvas, future TUI, etc.).
+//
+// Format:
+//   workspace:abc-123 → "Workspace (abc-123)"   (UUID short-prefixed)
+//   team:t-1          → "Team (t-1)"
+//   org:acme          → "Org (acme)"
+//   custom:foo        → "foo"                   (operator-defined; raw)
+func namespaceLabel(name string, kind contract.NamespaceKind) string {
+	suffix := ""
+	if i := indexOfColon(name); i >= 0 && i+1 < len(name) {
+		suffix = name[i+1:]
+	}
+	switch kind {
+	case contract.NamespaceKindWorkspace:
+		return "Workspace (" + shortID(suffix) + ")"
+	case contract.NamespaceKindTeam:
+		return "Team (" + shortID(suffix) + ")"
+	case contract.NamespaceKindOrg:
+		return "Org (" + suffix + ")"
+	case contract.NamespaceKindCustom:
+		// Custom namespaces are operator-defined; surface the raw
+		// suffix so they can label them however they want.
+		if suffix == "" {
+			return name
+		}
+		return suffix
+	default:
+		return name
+	}
+}
+
+// shortID truncates a UUID-like string to the first 8 chars so the
+// dropdown stays readable. Keeps the full id available via the
+// `name` field for click-to-copy / debugging.
+func shortID(s string) string {
+	if len(s) <= 8 {
+		return s
+	}
+	return s[:8]
+}
+
+// indexOfColon is strings.IndexByte without the import, kept inline so
+// the helper stays trivially auditable next to namespaceLabel.
+func indexOfColon(s string) int {
+	for i := 0; i < len(s); i++ {
+		if s[i] == ':' {
+			return i
+		}
+	}
+	return -1
+}
+
+// parseLimit validates the ?limit= query value. Defaults +
+// clamps mirror memoriesV2DefaultLimit / memoriesV2MaxLimit.
+func parseLimit(raw string) int {
+	if raw == "" {
+		return memoriesV2DefaultLimit
+	}
+	n, err := strconv.Atoi(raw)
+	if err != nil || n <= 0 {
+		return memoriesV2DefaultLimit
+	}
+	if n > memoriesV2MaxLimit {
+		return memoriesV2MaxLimit
+	}
+	return n
+}
+
diff --git a/workspace-server/internal/handlers/memories_v2_test.go b/workspace-server/internal/handlers/memories_v2_test.go
new file mode 100644
index 00000000..2b7fc993
--- /dev/null
+++ b/workspace-server/internal/handlers/memories_v2_test.go
@@ -0,0 +1,669 @@
+package handlers
+
+// memories_v2_test.go — comprehensive coverage for the Memory v2
+// canvas-facing HTTP surface. Pinned shape:
+//
+//   - 503 path when plugin unwired (every route)
+//   - GET /v2/namespaces success + readable/writable propagation
+//   - GET /v2/namespaces error path (resolver failure on either call)
+//   - GET /v2/memories: empty intersection, namespace passthrough,
+//     query+kind+limit propagation, plugin error mapping
+//   - DELETE /v2/memories/:id: success, plugin not_found→404, other
+//     plugin errors→502, missing memoryId→400
+//   - View shaping: namespaceLabel for all four kinds + truncation,
+//     memoryToView with/without propagation source, parseLimit edge
+//     cases (default, negative, zero, over-cap, non-numeric)
+//
+// Tests use the same `memoryPluginAPI` / `namespaceResolverAPI` fakes
+// the MCP v2 tests use so we don't spin up a real plugin server.
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/memory/contract"
+	"github.com/Molecule-AI/molecule-monorepo/platform/internal/memory/namespace"
+	"github.com/gin-gonic/gin"
+)
+
+// ─────────────────────────────────────────────────────────────────────────────
+// Fakes
+// ─────────────────────────────────────────────────────────────────────────────
+
+type fakePlugin struct {
+	searchResp *contract.SearchResponse
+	searchErr  error
+	searchReq  contract.SearchRequest // captured for assertion
+	forgetErr  error
+	forgetID   string
+	forgetReq  contract.ForgetRequest
+}
+
+func (f *fakePlugin) CommitMemory(ctx context.Context, ns string, body contract.MemoryWrite) (*contract.MemoryWriteResponse, error) {
+	return nil, errors.New("not implemented in fake")
+}
+func (f *fakePlugin) Search(ctx context.Context, body contract.SearchRequest) (*contract.SearchResponse, error) {
+	f.searchReq = body
+	if f.searchErr != nil {
+		return nil, f.searchErr
+	}
+	return f.searchResp, nil
+}
+func (f *fakePlugin) ForgetMemory(ctx context.Context, id string, body contract.ForgetRequest) error {
+	f.forgetID = id
+	f.forgetReq = body
+	return f.forgetErr
+}
+
+type fakeNSResolver struct {
+	readable     []namespace.Namespace
+	readableErr  error
+	writable     []namespace.Namespace
+	writableErr  error
+	intersect    []string
+	intersectErr error
+	intersectIn  []string // captured
+}
+
+func (f *fakeNSResolver) ReadableNamespaces(ctx context.Context, ws string) ([]namespace.Namespace, error) {
+	return f.readable, f.readableErr
+}
+func (f *fakeNSResolver) WritableNamespaces(ctx context.Context, ws string) ([]namespace.Namespace, error) {
+	return f.writable, f.writableErr
+}
+func (f *fakeNSResolver) CanWrite(ctx context.Context, ws, ns string) (bool, error) {
+	return true, nil
+}
+func (f *fakeNSResolver) IntersectReadable(ctx context.Context, ws string, requested []string) ([]string, error) {
+	f.intersectIn = requested
+	return f.intersect, f.intersectErr
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// Test helpers
+// ─────────────────────────────────────────────────────────────────────────────
+
+func init() {
+	gin.SetMode(gin.TestMode)
+}
+
+// newWiredHandler returns a handler with both the fake plugin + fake
+// resolver attached. Tests that need the unwired (503) path use
+// NewMemoriesV2Handler() directly.
+func newWiredHandler(p *fakePlugin, r *fakeNSResolver) *MemoriesV2Handler {
+	return NewMemoriesV2Handler().withMemoryV2APIs(p, r)
+}
+
+func doRequest(t *testing.T, h *MemoriesV2Handler, method, path string, params gin.Params) *httptest.ResponseRecorder {
+	t.Helper()
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Params = params
+	req := httptest.NewRequest(method, path, nil)
+	c.Request = req
+	switch {
+	case method == http.MethodGet && strings.HasSuffix(path, "/v2/namespaces"):
+		h.Namespaces(c)
+	case method == http.MethodGet && strings.Contains(path, "/v2/memories"):
+		h.Search(c)
+	case method == http.MethodDelete:
+		h.Forget(c)
+	default:
+		t.Fatalf("doRequest: don't know how to dispatch %s %s", method, path)
+	}
+	return rec
+}
+
+func mustJSON(t *testing.T, body []byte, out interface{}) {
+	t.Helper()
+	if err := json.Unmarshal(body, out); err != nil {
+		t.Fatalf("json decode: %v\nbody=%s", err, string(body))
+	}
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// 503 — plugin unwired
+// ─────────────────────────────────────────────────────────────────────────────
+
+func TestMemoriesV2_PluginUnwired_All503(t *testing.T) {
+	h := NewMemoriesV2Handler() // no WithMemoryV2 / withMemoryV2APIs
+
+	cases := []struct {
+		name   string
+		method string
+		path   string
+		params gin.Params
+	}{
+		{"namespaces", http.MethodGet, "/workspaces/ws-a/v2/namespaces", gin.Params{{Key: "id", Value: "ws-a"}}},
+		{"search", http.MethodGet, "/workspaces/ws-a/v2/memories", gin.Params{{Key: "id", Value: "ws-a"}}},
+		{"forget", http.MethodDelete, "/workspaces/ws-a/v2/memories/m-1", gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: "m-1"}}},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			rec := doRequest(t, h, tc.method, tc.path, tc.params)
+			if rec.Code != http.StatusServiceUnavailable {
+				t.Errorf("expected 503, got %d", rec.Code)
+			}
+			var body map[string]string
+			mustJSON(t, rec.Body.Bytes(), &body)
+			if !strings.Contains(body["error"], "MEMORY_PLUGIN_URL") {
+				t.Errorf("503 body missing operator hint, got: %q", body["error"])
+			}
+		})
+	}
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// GET /v2/namespaces
+// ─────────────────────────────────────────────────────────────────────────────
+
+func TestMemoriesV2_Namespaces_Success(t *testing.T) {
+	resolver := &fakeNSResolver{
+		readable: []namespace.Namespace{
+			{Name: "workspace:abc-1234-5678", Kind: contract.NamespaceKindWorkspace},
+			{Name: "team:t-99", Kind: contract.NamespaceKindTeam},
+			{Name: "org:acme", Kind: contract.NamespaceKindOrg},
+			{Name: "custom:special", Kind: contract.NamespaceKindCustom},
+		},
+		writable: []namespace.Namespace{
+			{Name: "workspace:abc-1234-5678", Kind: contract.NamespaceKindWorkspace},
+		},
+	}
+	h := newWiredHandler(&fakePlugin{}, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/namespaces",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != 200 {
+		t.Fatalf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	var body NamespacesResponse
+	mustJSON(t, rec.Body.Bytes(), &body)
+
+	if len(body.Readable) != 4 {
+		t.Errorf("expected 4 readable, got %d", len(body.Readable))
+	}
+	if len(body.Writable) != 1 {
+		t.Errorf("expected 1 writable, got %d", len(body.Writable))
+	}
+
+	// Label shaping pinned exactly — drift would silently break the
+	// dropdown rendering.
+	wantLabels := map[string]string{
+		"workspace:abc-1234-5678": "Workspace (abc-1234)",
+		"team:t-99":               "Team (t-99)",
+		"org:acme":                "Org (acme)",
+		"custom:special":          "special",
+	}
+	for _, v := range body.Readable {
+		want, ok := wantLabels[v.Name]
+		if !ok {
+			t.Errorf("unexpected namespace name %q", v.Name)
+			continue
+		}
+		if v.Label != want {
+			t.Errorf("namespace %q: want label %q, got %q", v.Name, want, v.Label)
+		}
+	}
+}
+
+func TestMemoriesV2_Namespaces_ReadableError(t *testing.T) {
+	resolver := &fakeNSResolver{readableErr: errors.New("boom")}
+	h := newWiredHandler(&fakePlugin{}, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/namespaces",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != http.StatusInternalServerError {
+		t.Errorf("expected 500, got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Namespaces_WritableError(t *testing.T) {
+	resolver := &fakeNSResolver{
+		readable:    []namespace.Namespace{},
+		writableErr: errors.New("boom"),
+	}
+	h := newWiredHandler(&fakePlugin{}, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/namespaces",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != http.StatusInternalServerError {
+		t.Errorf("expected 500, got %d", rec.Code)
+	}
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// GET /v2/memories — search path
+// ─────────────────────────────────────────────────────────────────────────────
+
+func TestMemoriesV2_Search_NoReadableNamespaces_EmptyResult(t *testing.T) {
+	// Empty intersection (e.g. workspace just provisioned, plugin
+	// hasn't created namespaces yet, OR caller asked for ns they
+	// can't read). Expected: 200 with empty memories array, NOT 404.
+	resolver := &fakeNSResolver{intersect: []string{}}
+	plugin := &fakePlugin{searchResp: &contract.SearchResponse{Memories: []contract.Memory{}}}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != 200 {
+		t.Errorf("expected 200, got %d", rec.Code)
+	}
+	var body MemoriesResponse
+	mustJSON(t, rec.Body.Bytes(), &body)
+	if body.Memories == nil {
+		t.Error("Memories should be empty array, not nil — JSON would render null")
+	}
+	if len(body.Memories) != 0 {
+		t.Errorf("expected empty memories, got %d", len(body.Memories))
+	}
+	// Plugin must NOT be called when intersection is empty.
+	if plugin.searchReq.Namespaces != nil {
+		t.Error("plugin Search should not be called when intersection is empty")
+	}
+}
+
+func TestMemoriesV2_Search_FullPath_NamespaceQueryKindLimit(t *testing.T) {
+	expiresAt := time.Now().Add(24 * time.Hour)
+	resolver := &fakeNSResolver{intersect: []string{"workspace:ws-a"}}
+	score := 0.87
+	plugin := &fakePlugin{
+		searchResp: &contract.SearchResponse{
+			Memories: []contract.Memory{
+				{
+					ID:        "m-1",
+					Namespace: "workspace:ws-a",
+					Content:   "fact one",
+					Kind:      contract.MemoryKindFact,
+					Source:    contract.MemorySourceAgent,
+					Pin:       true,
+					ExpiresAt: &expiresAt,
+					CreatedAt: time.Now(),
+					Score:     &score,
+					Propagation: map[string]interface{}{
+						"source_workspace_id": "ws-peer-42",
+					},
+				},
+			},
+		},
+	}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Params = gin.Params{{Key: "id", Value: "ws-a"}}
+	c.Request = httptest.NewRequest(http.MethodGet,
+		"/workspaces/ws-a/v2/memories?namespace=workspace:ws-a&q=hello&kind=fact&limit=10", nil)
+	h.Search(c)
+
+	if rec.Code != 200 {
+		t.Fatalf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	// Resolver received the requested namespace as a single-element list
+	if len(resolver.intersectIn) != 1 || resolver.intersectIn[0] != "workspace:ws-a" {
+		t.Errorf("resolver.IntersectReadable received %v, want [workspace:ws-a]", resolver.intersectIn)
+	}
+	// Plugin received query + kind + limit propagated through
+	if plugin.searchReq.Query != "hello" {
+		t.Errorf("plugin.Query=%q, want hello", plugin.searchReq.Query)
+	}
+	if len(plugin.searchReq.Kinds) != 1 || plugin.searchReq.Kinds[0] != contract.MemoryKindFact {
+		t.Errorf("plugin.Kinds=%v, want [fact]", plugin.searchReq.Kinds)
+	}
+	if plugin.searchReq.Limit != 10 {
+		t.Errorf("plugin.Limit=%d, want 10", plugin.searchReq.Limit)
+	}
+	// Response shape — pin/expires_at/score/source_workspace_id all
+	// surfaced into MemoryView so the canvas doesn't have to dig
+	// through propagation map.
+	var body MemoriesResponse
+	mustJSON(t, rec.Body.Bytes(), &body)
+	if len(body.Memories) != 1 {
+		t.Fatalf("expected 1 memory, got %d", len(body.Memories))
+	}
+	m := body.Memories[0]
+	if !m.Pin {
+		t.Error("Pin not propagated")
+	}
+	if m.ExpiresAt == nil {
+		t.Error("ExpiresAt not propagated")
+	}
+	if m.Score == nil || *m.Score != 0.87 {
+		t.Errorf("Score=%v, want 0.87", m.Score)
+	}
+	if m.SourceWorkspaceID != "ws-peer-42" {
+		t.Errorf("SourceWorkspaceID=%q, want ws-peer-42", m.SourceWorkspaceID)
+	}
+}
+
+func TestMemoriesV2_Search_NoNamespaceQuery_AllReadable(t *testing.T) {
+	// No ?namespace= → resolver.IntersectReadable receives nil (empty
+	// requested) and returns ALL readable. Plugin gets full set.
+	resolver := &fakeNSResolver{intersect: []string{"workspace:ws-a", "team:t-1"}}
+	plugin := &fakePlugin{searchResp: &contract.SearchResponse{}}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != 200 {
+		t.Errorf("expected 200, got %d", rec.Code)
+	}
+	if resolver.intersectIn != nil {
+		t.Errorf("requested should be nil for unscoped query, got %v", resolver.intersectIn)
+	}
+	if len(plugin.searchReq.Namespaces) != 2 {
+		t.Errorf("plugin.Namespaces=%v, want both readable", plugin.searchReq.Namespaces)
+	}
+}
+
+func TestMemoriesV2_Search_IntersectError(t *testing.T) {
+	resolver := &fakeNSResolver{intersectErr: errors.New("db down")}
+	h := newWiredHandler(&fakePlugin{}, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != http.StatusInternalServerError {
+		t.Errorf("expected 500, got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Search_PluginError(t *testing.T) {
+	resolver := &fakeNSResolver{intersect: []string{"workspace:ws-a"}}
+	plugin := &fakePlugin{searchErr: errors.New("plugin down")}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != http.StatusBadGateway {
+		t.Errorf("expected 502 (plugin error), got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Search_PropagationMissing_NoSourceWorkspaceID(t *testing.T) {
+	resolver := &fakeNSResolver{intersect: []string{"workspace:ws-a"}}
+	plugin := &fakePlugin{
+		searchResp: &contract.SearchResponse{
+			Memories: []contract.Memory{
+				{ID: "m-1", Namespace: "workspace:ws-a", Content: "no propagation"},
+			},
+		},
+	}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	var body MemoriesResponse
+	mustJSON(t, rec.Body.Bytes(), &body)
+	if len(body.Memories) != 1 || body.Memories[0].SourceWorkspaceID != "" {
+		t.Errorf("SourceWorkspaceID should be empty when propagation is nil, got %q", body.Memories[0].SourceWorkspaceID)
+	}
+}
+
+func TestMemoriesV2_Search_PropagationWrongType_DoesNotPanic(t *testing.T) {
+	resolver := &fakeNSResolver{intersect: []string{"workspace:ws-a"}}
+	plugin := &fakePlugin{
+		searchResp: &contract.SearchResponse{
+			Memories: []contract.Memory{
+				{
+					ID:      "m-1",
+					Content: "wrong-type propagation",
+					Propagation: map[string]interface{}{
+						"source_workspace_id": 12345, // int, not string
+					},
+				},
+			},
+		},
+	}
+	h := newWiredHandler(plugin, resolver)
+
+	rec := doRequest(t, h, http.MethodGet, "/workspaces/ws-a/v2/memories",
+		gin.Params{{Key: "id", Value: "ws-a"}})
+	if rec.Code != 200 {
+		t.Fatalf("expected 200 (graceful), got %d", rec.Code)
+	}
+	var body MemoriesResponse
+	mustJSON(t, rec.Body.Bytes(), &body)
+	// Wrong-typed prop entry → empty SourceWorkspaceID, no panic.
+	if body.Memories[0].SourceWorkspaceID != "" {
+		t.Errorf("expected empty SourceWorkspaceID for non-string propagation, got %q", body.Memories[0].SourceWorkspaceID)
+	}
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// DELETE /v2/memories/:memoryId
+// ─────────────────────────────────────────────────────────────────────────────
+
+func TestMemoriesV2_Forget_Success(t *testing.T) {
+	plugin := &fakePlugin{} // forgetErr nil
+	h := newWiredHandler(plugin, &fakeNSResolver{})
+
+	rec := doRequest(t, h, http.MethodDelete, "/workspaces/ws-a/v2/memories/mem-42",
+		gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: "mem-42"}})
+	if rec.Code != 200 {
+		t.Errorf("expected 200, got %d body=%s", rec.Code, rec.Body.String())
+	}
+	if plugin.forgetID != "mem-42" {
+		t.Errorf("plugin received memoryID=%q, want mem-42", plugin.forgetID)
+	}
+	if plugin.forgetReq.RequestedByNamespace != "workspace:ws-a" {
+		t.Errorf("requested_by_namespace=%q, want workspace:ws-a", plugin.forgetReq.RequestedByNamespace)
+	}
+}
+
+func TestMemoriesV2_Forget_PluginNotFound_Maps404(t *testing.T) {
+	plugin := &fakePlugin{
+		forgetErr: &contract.Error{Code: contract.ErrorCodeNotFound, Message: "no such memory"},
+	}
+	h := newWiredHandler(plugin, &fakeNSResolver{})
+
+	rec := doRequest(t, h, http.MethodDelete, "/workspaces/ws-a/v2/memories/m-1",
+		gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: "m-1"}})
+	if rec.Code != http.StatusNotFound {
+		t.Errorf("expected 404, got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Forget_PluginOtherError_Maps502(t *testing.T) {
+	plugin := &fakePlugin{
+		forgetErr: &contract.Error{Code: contract.ErrorCodeInternal, Message: "db dead"},
+	}
+	h := newWiredHandler(plugin, &fakeNSResolver{})
+
+	rec := doRequest(t, h, http.MethodDelete, "/workspaces/ws-a/v2/memories/m-1",
+		gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: "m-1"}})
+	if rec.Code != http.StatusBadGateway {
+		t.Errorf("expected 502, got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Forget_NonContractError_Maps502(t *testing.T) {
+	// A raw error (e.g. transport failure) — not a contract.Error —
+	// also bubbles up as 502.
+	plugin := &fakePlugin{forgetErr: errors.New("connection reset")}
+	h := newWiredHandler(plugin, &fakeNSResolver{})
+
+	rec := doRequest(t, h, http.MethodDelete, "/workspaces/ws-a/v2/memories/m-1",
+		gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: "m-1"}})
+	if rec.Code != http.StatusBadGateway {
+		t.Errorf("expected 502, got %d", rec.Code)
+	}
+}
+
+func TestMemoriesV2_Forget_MissingMemoryID_400(t *testing.T) {
+	h := newWiredHandler(&fakePlugin{}, &fakeNSResolver{})
+	rec := doRequest(t, h, http.MethodDelete, "/workspaces/ws-a/v2/memories/",
+		gin.Params{{Key: "id", Value: "ws-a"}, {Key: "memoryId", Value: ""}})
+	if rec.Code != http.StatusBadRequest {
+		t.Errorf("expected 400, got %d", rec.Code)
+	}
+}
+
+// ─────────────────────────────────────────────────────────────────────────────
+// View-shaping unit tests — pin individual helpers
+// ─────────────────────────────────────────────────────────────────────────────
+
+func TestNamespaceLabel_AllKinds(t *testing.T) {
+	cases := []struct {
+		name string
+		kind contract.NamespaceKind
+		want string
+	}{
+		{"workspace:abcdefghij", contract.NamespaceKindWorkspace, "Workspace (abcdefgh)"}, // truncated to 8
+		{"workspace:abc", contract.NamespaceKindWorkspace, "Workspace (abc)"},             // shorter than 8, kept as-is
+		{"team:t-99", contract.NamespaceKindTeam, "Team (t-99)"},
+		{"org:acme", contract.NamespaceKindOrg, "Org (acme)"},
+		{"custom:my-ns", contract.NamespaceKindCustom, "my-ns"},
+		{"custom:", contract.NamespaceKindCustom, "custom:"}, // empty suffix → fallback to raw name
+		{"weird-no-colon", contract.NamespaceKindWorkspace, "Workspace ()"},
+		{"unknown:x", contract.NamespaceKind("future"), "unknown:x"}, // unknown kind → fallback to raw name
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got := namespaceLabel(tc.name, tc.kind)
+			if got != tc.want {
+				t.Errorf("namespaceLabel(%q, %q) = %q, want %q", tc.name, tc.kind, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestParseLimit(t *testing.T) {
+	cases := []struct {
+		raw  string
+		want int
+	}{
+		{"", memoriesV2DefaultLimit},
+		{"10", 10},
+		{"0", memoriesV2DefaultLimit},        // ≤0 → default, not error
+		{"-5", memoriesV2DefaultLimit},       // negative → default
+		{"abc", memoriesV2DefaultLimit},      // non-numeric → default
+		{"99999", memoriesV2MaxLimit},        // over cap → clamped
+		{"100", memoriesV2MaxLimit},          // exactly cap → kept
+		{"99", 99},                           // just under cap → kept
+	}
+	for _, tc := range cases {
+		t.Run("raw="+tc.raw, func(t *testing.T) {
+			if got := parseLimit(tc.raw); got != tc.want {
+				t.Errorf("parseLimit(%q) = %d, want %d", tc.raw, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestMemoryToView_AllFieldsPropagated(t *testing.T) {
+	now := time.Now()
+	exp := now.Add(time.Hour)
+	score := 0.95
+	m := contract.Memory{
+		ID:        "m-1",
+		Namespace: "team:t-1",
+		Content:   "hello",
+		Kind:      contract.MemoryKindSummary,
+		Source:    contract.MemorySourceUser,
+		Pin:       true,
+		ExpiresAt: &exp,
+		CreatedAt: now,
+		Score:     &score,
+		Propagation: map[string]interface{}{
+			"source_workspace_id": "ws-other",
+		},
+	}
+	v := memoryToView(m)
+	if v.ID != m.ID || v.Namespace != m.Namespace || v.Content != m.Content {
+		t.Errorf("basic fields: %+v", v)
+	}
+	if v.Kind != contract.MemoryKindSummary || v.Source != contract.MemorySourceUser {
+		t.Errorf("kind/source: %+v", v)
+	}
+	if !v.Pin || v.ExpiresAt == nil || v.Score == nil || *v.Score != 0.95 {
+		t.Errorf("pin/expires/score: %+v", v)
+	}
+	if v.SourceWorkspaceID != "ws-other" {
+		t.Errorf("SourceWorkspaceID=%q, want ws-other", v.SourceWorkspaceID)
+	}
+}
+
+func TestNamespacesToViews_PreservesOrder(t *testing.T) {
+	in := []namespace.Namespace{
+		{Name: "team:t1", Kind: contract.NamespaceKindTeam},
+		{Name: "workspace:w1", Kind: contract.NamespaceKindWorkspace},
+	}
+	out := namespacesToViews(in)
+	if len(out) != 2 {
+		t.Fatalf("len=%d", len(out))
+	}
+	// Resolver determines order; we just preserve it. (Sorting can be
+	// added at the resolver layer if the canvas needs it.)
+	if out[0].Name != "team:t1" || out[1].Name != "workspace:w1" {
+		t.Errorf("order not preserved: %+v", out)
+	}
+}
+
+func TestNamespacesToViews_EmptyInput_EmptySlice(t *testing.T) {
+	out := namespacesToViews(nil)
+	if out == nil {
+		t.Error("expected empty slice, not nil — JSON-marshals as null otherwise")
+	}
+	if len(out) != 0 {
+		t.Errorf("expected len 0, got %d", len(out))
+	}
+}
+
+func TestIndexOfColon(t *testing.T) {
+	cases := []struct {
+		s    string
+		want int
+	}{
+		{"abc:def", 3},
+		{":foo", 0},
+		{"nocolon", -1},
+		{"", -1},
+		{"a:b:c", 1}, // first colon only
+	}
+	for _, tc := range cases {
+		if got := indexOfColon(tc.s); got != tc.want {
+			t.Errorf("indexOfColon(%q) = %d, want %d", tc.s, got, tc.want)
+		}
+	}
+}
+
+func TestWithMemoryV2_FluentReturnsReceiver(t *testing.T) {
+	// WithMemoryV2 is the production wiring path (takes *client.Client +
+	// *namespace.Resolver). withMemoryV2APIs is the test path. The
+	// production call is structural — assigns the two fields and
+	// returns the receiver — but we still want a 100% coverage gate
+	// to catch a future refactor that accidentally drops the fluent
+	// return (breaking the boot-time chain in router.go).
+	//
+	// We can't pass nil for the typed pointers and call available()
+	// here because Go interface-with-nil-pointer is non-nil at the
+	// interface level — `available()` would not detect that as
+	// "unwired". The unwired-plugin behaviour is exhaustively
+	// covered by TestMemoriesV2_PluginUnwired_All503; this test just
+	// pins the fluent contract.
+	h := NewMemoriesV2Handler()
+	got := h.WithMemoryV2(nil, nil)
+	if got != h {
+		t.Error("WithMemoryV2 must return receiver for fluent chaining")
+	}
+}
+
+func TestShortID(t *testing.T) {
+	cases := map[string]string{
+		"":                    "",
+		"short":               "short",
+		"exactly8":            "exactly8",
+		"longer-than-eight":   "longer-t",
+		"abc-1234-5678-90ab":  "abc-1234",
+	}
+	for in, want := range cases {
+		if got := shortID(in); got != want {
+			t.Errorf("shortID(%q) = %q, want %q", in, got, want)
+		}
+	}
+}
diff --git a/workspace-server/internal/router/router.go b/workspace-server/internal/router/router.go
index ae928f2f..a074df7f 100644
--- a/workspace-server/internal/router/router.go
+++ b/workspace-server/internal/router/router.go
@@ -232,6 +232,20 @@ func Setup(hub *ws.Hub, broadcaster *events.Broadcaster, prov *provisioner.Provi
 		wsAuth.DELETE("/memories/:memoryId", memsh.Delete)
 		wsAuth.PATCH("/memories/:memoryId", memsh.Update)
 
+		// Memory v2 — canvas reads through the plugin so the Memory
+		// tab surfaces post-cutover state (memory_records) instead
+		// of the frozen agent_memories table that memsh.Search hits.
+		// Wired only when MEMORY_PLUGIN_URL is configured; absent
+		// plugin → endpoints return 503 with a clear hint instead
+		// of nil-deref crashing the canvas.
+		memv2 := handlers.NewMemoriesV2Handler()
+		if memBundle != nil {
+			memv2.WithMemoryV2(memBundle.Plugin, memBundle.Resolver)
+		}
+		wsAuth.GET("/v2/namespaces", memv2.Namespaces)
+		wsAuth.GET("/v2/memories", memv2.Search)
+		wsAuth.DELETE("/v2/memories/:memoryId", memv2.Forget)
+
 		// Approvals
 		apph := handlers.NewApprovalsHandler(broadcaster)
 		wsAuth.POST("/approvals", apph.Create)
diff --git a/workspace/a2a_client.py b/workspace/a2a_client.py
index 7cd151bf..16eb4b9c 100644
--- a/workspace/a2a_client.py
+++ b/workspace/a2a_client.py
@@ -584,6 +584,24 @@ async def send_a2a_message(peer_id: str, message: str, source_workspace_id: str
                     else:
                         detail = "JSON-RPC error with no message"
                     return f"{_A2A_ERROR_PREFIX}{detail} [target={target_url}]"
+                elif data.get("status") == "queued" and data.get("delivery_mode") == "poll":
+                    # Workspace-server's poll-mode short-circuit envelope
+                    # (workspace-server/internal/handlers/a2a_proxy.go ~line 402).
+                    # The peer is poll-mode and has no URL to dispatch to, so
+                    # the server queued the message for the peer's next inbox
+                    # poll instead of forwarding it. Delivery is acknowledged
+                    # but pending consumption.
+                    #
+                    # Pre-fix this fell through to the "unexpected response
+                    # shape" error path → callers logged false failures, then
+                    # delegate_task retried, and the peer received duplicate
+                    # delegations. Issue #2967.
+                    method = data.get("method") or "message/send"
+                    logger.info(
+                        "send_a2a_message: queued for poll-mode peer (method=%s, target=%s)",
+                        method, target_url,
+                    )
+                    return f"queued for poll-mode peer (method={method})"
                 return f"{_A2A_ERROR_PREFIX}unexpected response shape (no result, no error): {str(data)[:200]} [target={target_url}]"
             except _TRANSIENT_HTTP_ERRORS as e:
                 last_exc = e
diff --git a/workspace/mcp_cli.py b/workspace/mcp_cli.py
index e890a66d..e9033649 100644
--- a/workspace/mcp_cli.py
+++ b/workspace/mcp_cli.py
@@ -93,7 +93,34 @@ def main() -> None:
         ``{"id": ..., "token": ...}`` entries. One register + heartbeat
         + inbox poller per entry; messages from any workspace land in
         the same agent inbox tagged with ``arrival_workspace_id``.
+
+    Subcommand:
+      ``molecule-mcp doctor`` runs an onboarding diagnostic against the
+      current shell environment + platform reachability and exits.
+      Closes Ryan's #2934 item 6.
     """
+    # Subcommand dispatch — must come BEFORE env-var validation so
+    # `molecule-mcp doctor` can run on a partially-configured shell
+    # and tell the operator what's missing. Argv shapes:
+    #   molecule-mcp           → run server (this function's main path)
+    #   molecule-mcp doctor    → run diagnostic, exit
+    #   molecule-mcp --help    → defer to doctor for now (no other
+    #                             flags are supported yet)
+    if len(sys.argv) > 1:
+        if sys.argv[1] in ("doctor", "--doctor"):
+            import mcp_doctor
+            sys.exit(mcp_doctor.run())
+        if sys.argv[1] in ("--help", "-h", "help"):
+            print(
+                "molecule-mcp — Molecule AI universal MCP server\n\n"
+                "Usage:\n"
+                "  molecule-mcp           Run the MCP stdio server (registers + heartbeats)\n"
+                "  molecule-mcp doctor    Run onboarding diagnostic + exit\n\n"
+                "Required env: PLATFORM_URL, WORKSPACE_ID (or MOLECULE_WORKSPACES),\n"
+                "              MOLECULE_WORKSPACE_TOKEN (or MOLECULE_WORKSPACE_TOKEN_FILE)\n",
+            )
+            sys.exit(0)
+
     if not os.environ.get("PLATFORM_URL", "").strip():
         _print_missing_env_help(
             ["PLATFORM_URL"],
diff --git a/workspace/mcp_doctor.py b/workspace/mcp_doctor.py
new file mode 100644
index 00000000..ab788076
--- /dev/null
+++ b/workspace/mcp_doctor.py
@@ -0,0 +1,426 @@
+"""molecule-mcp doctor — diagnostic subcommand for first-run install.
+
+Run via ``molecule-mcp doctor``. Prints a checklist of common
+onboarding failure modes and concrete next-step suggestions for each
+failed check.
+
+Closes Ryan's #2934 item 6 ("Add a molecule-mcp doctor subcommand —
+this single command would have saved me 30 of the 45 minutes").
+Pairs with #2935 (Python>=3.11 callout, PATH guidance, TOKEN_FILE
+support) — those fixed the snippet, this gives the operator a way to
+self-diagnose when something still goes wrong.
+
+Six checks, in operator-encounter order:
+
+    1. Python version    — wheel requires >=3.11 (pip says
+                            "no versions found" on older).
+    2. Wheel install     — molecule_runtime importable + version reported.
+    3. PATH for molecule-mcp — pip user-site installs land at
+                            ~/Library/Python/3.X/bin which isn't on
+                            PATH on a fresh macOS shell. Most common
+                            "claude mcp add can't find molecule-mcp"
+                            cause.
+    4. Env vars          — PLATFORM_URL set + reachable;
+                            WORKSPACE_ID set; auth token resolvable
+                            (env or *_FILE or .auth_token).
+    5. Platform health   — GET ${PLATFORM_URL}/healthz returns 2xx.
+                            Catches DNS/firewall/wrong-scheme issues
+                            before the operator hits the real
+                            register call.
+    6. Token auth         — POST ${PLATFORM_URL}/registry/heartbeat
+                            with the resolved workspace_id+token
+                            returns 2xx. End-to-end auth verification.
+                            Uses heartbeat (idempotent timestamp
+                            update) instead of register (UPSERT —
+                            would clobber agent_card metadata) so
+                            the doctor is safe to run against a
+                            live workspace.
+
+Each check prints one of:
+    [OK]   <one-line status>
+    [WARN] <one-line status>      next: <fix suggestion>
+    [FAIL] <one-line status>      next: <fix suggestion>
+
+Exit 0 if all pass or only WARNs; exit 1 if any FAIL — so the
+subcommand is scriptable from CI / install-checks too.
+
+Out of scope for now (deferred follow-ups):
+    - Claude Code-specific checks (parse ~/.claude.json, verify each
+      MCP entry is plugin-sourced + dev-channels flag is set). That's
+      a separate Claude-Code-specific doctor and lives in the
+      claude-code-channel plugin, not the universal-MCP doctor.
+    - Automated remediation (running the suggested fix). Doctor is
+      a diagnostic tool — it tells the operator what's wrong + how
+      to fix it, doesn't apply changes.
+"""
+from __future__ import annotations
+
+import importlib
+import importlib.metadata
+import os
+import shutil
+import sys
+from typing import Optional
+
+# urllib avoids a hard dep on `requests` for the doctor — the real
+# CLI already imports requests via mcp_heartbeat, but doctor should
+# keep working even on a partial install where requests is missing
+# (that itself is a finding worth surfacing).
+from urllib import request as urllib_request
+from urllib.error import URLError
+
+
+# ANSI colors are friendly on TTYs; auto-disable on pipe / NO_COLOR
+# for CI logs where the escape sequences clutter the diff.
+def _color(name: str) -> str:
+    if not sys.stdout.isatty() or os.environ.get("NO_COLOR"):
+        return ""
+    return {
+        "green": "\033[32m",
+        "yellow": "\033[33m",
+        "red": "\033[31m",
+        "dim": "\033[2m",
+        "reset": "\033[0m",
+    }.get(name, "")
+
+
+def _ok(label: str, msg: str) -> None:
+    print(f"  {_color('green')}[OK]{_color('reset')}   {label}: {msg}")
+
+
+def _warn(label: str, msg: str, fix: str) -> None:
+    print(f"  {_color('yellow')}[WARN]{_color('reset')} {label}: {msg}")
+    print(f"        {_color('dim')}next:{_color('reset')} {fix}")
+
+
+def _fail(label: str, msg: str, fix: str) -> None:
+    print(f"  {_color('red')}[FAIL]{_color('reset')} {label}: {msg}")
+    print(f"        {_color('dim')}next:{_color('reset')} {fix}")
+
+
+# Each check returns a "ok" | "warn" | "fail" verdict so the caller
+# can compute an exit code without re-walking the print stream.
+Verdict = str  # "ok" | "warn" | "fail"
+
+
+def check_python_version() -> Verdict:
+    label = "Python version"
+    major, minor = sys.version_info[:2]
+    if (major, minor) >= (3, 11):
+        _ok(label, f"Python {major}.{minor} (wheel requires >=3.11)")
+        return "ok"
+    _fail(
+        label,
+        f"Python {major}.{minor} is below the wheel's >=3.11 floor",
+        "upgrade Python (brew install python@3.12 / apt install python3.12) "
+        "or run molecule-mcp via a 3.11+ venv.",
+    )
+    return "fail"
+
+
+def check_wheel_install() -> Verdict:
+    label = "Wheel install"
+    try:
+        version = importlib.metadata.version("molecule-ai-workspace-runtime")
+    except importlib.metadata.PackageNotFoundError:
+        _fail(
+            label,
+            "molecule-ai-workspace-runtime not found in this interpreter's site-packages",
+            "pip install molecule-ai-workspace-runtime "
+            "(or pipx install molecule-ai-workspace-runtime to get the "
+            "binary on PATH automatically).",
+        )
+        return "fail"
+    try:
+        importlib.import_module("molecule_runtime.mcp_cli")
+    except ImportError as e:
+        _fail(
+            label,
+            f"package found ({version}) but `molecule_runtime.mcp_cli` won't import: {e}",
+            "reinstall the wheel (pip install --force-reinstall "
+            "molecule-ai-workspace-runtime); if it still fails, file "
+            "a bug with the traceback.",
+        )
+        return "fail"
+    _ok(label, f"molecule-ai-workspace-runtime=={version}")
+    return "ok"
+
+
+def check_path_for_binary() -> Verdict:
+    label = "PATH for molecule-mcp"
+    found = shutil.which("molecule-mcp")
+    if found:
+        _ok(label, f"resolves to {found}")
+        return "ok"
+    # Not on PATH — work out where pip put it so the suggestion is
+    # actionable instead of generic.
+    user_base = os.environ.get("PYTHONUSERBASE")
+    if not user_base:
+        try:
+            import site
+            user_base = site.getuserbase()
+        except Exception:
+            user_base = None
+    hint = (
+        f"add `{user_base}/bin` to PATH"
+        if user_base
+        else "switch to `pipx install molecule-ai-workspace-runtime` so the "
+             "binary lands in pipx's managed bin/ on PATH"
+    )
+    _fail(
+        label,
+        "molecule-mcp not found on PATH",
+        f"{hint}, or invoke via `python -m molecule_runtime.mcp_cli` directly.",
+    )
+    return "fail"
+
+
+def _resolve_token() -> tuple[Optional[str], Optional[str]]:
+    """Return ``(token_value, source_label)`` if the operator's
+    environment exposes a token, else ``(None, None)``.
+
+    Single source of truth used by both ``check_env_vars()`` (which
+    only needs the source label) and ``check_register()`` (which
+    needs the actual value to send a Bearer header). Keeping these
+    in one place means a future env-var addition only updates the
+    resolver — not two parallel readers that can drift.
+    """
+    val = os.environ.get("MOLECULE_WORKSPACE_TOKEN", "").strip()
+    if val:
+        return val, "env MOLECULE_WORKSPACE_TOKEN"
+    file_var = os.environ.get("MOLECULE_WORKSPACE_TOKEN_FILE", "").strip()
+    if file_var:
+        if os.path.isfile(file_var):
+            try:
+                from pathlib import Path as _Path
+                return (
+                    _Path(file_var).read_text().strip(),
+                    f"file {file_var} (via MOLECULE_WORKSPACE_TOKEN_FILE)",
+                )
+            except OSError:
+                return None, None
+        return None, None
+    # Per-runtime container path used by the in-platform path; rarely
+    # set on external setups but check anyway so the message is
+    # accurate for both shapes.
+    try:
+        import configs_dir
+        candidate = configs_dir.resolve() / ".auth_token"
+        if candidate.is_file():
+            try:
+                return candidate.read_text().strip(), f"file {candidate}"
+            except OSError:
+                return None, None
+    except Exception:
+        pass
+    return None, None
+
+
+def _resolve_token_summary() -> Optional[str]:
+    """Return just the source label (no secret value). Convenience
+    wrapper around :func:`_resolve_token` for callers that don't
+    need the value itself.
+    """
+    _, label = _resolve_token()
+    return label
+
+
+def check_env_vars() -> Verdict:
+    label = "Env vars"
+    missing: list[str] = []
+    if not os.environ.get("PLATFORM_URL", "").strip():
+        missing.append("PLATFORM_URL")
+    if not os.environ.get("WORKSPACE_ID", "").strip() and not os.environ.get(
+        "MOLECULE_WORKSPACES", "",
+    ).strip():
+        missing.append("WORKSPACE_ID (or MOLECULE_WORKSPACES)")
+    token_summary = _resolve_token_summary()
+    if not token_summary and not os.environ.get("MOLECULE_WORKSPACES", "").strip():
+        # MOLECULE_WORKSPACES is a JSON-array env that bundles its
+        # own per-workspace tokens — if it's set we trust the
+        # resolver to validate.
+        missing.append(
+            "MOLECULE_WORKSPACE_TOKEN (or MOLECULE_WORKSPACE_TOKEN_FILE, or "
+            "/configs/.auth_token)",
+        )
+    if missing:
+        _fail(
+            label,
+            f"unset: {', '.join(missing)}",
+            "see the canvas Connect-External-Agent modal — the snippet "
+            "exports all three. Use MOLECULE_WORKSPACE_TOKEN_FILE for the "
+            "token to keep secrets out of shell history.",
+        )
+        return "fail"
+    _ok(
+        label,
+        f"PLATFORM_URL + WORKSPACE_ID set; token from {token_summary or 'MOLECULE_WORKSPACES'}",
+    )
+    return "ok"
+
+
+def _http_get(url: str, timeout: float = 5.0) -> tuple[Optional[int], Optional[str]]:
+    """Best-effort GET that swallows transport errors and returns
+    (status, error_message). Status is None when the request couldn't
+    complete; error_message is None when the request returned 2xx.
+    """
+    try:
+        # Origin header — staging tenants enforce same-origin via WAF;
+        # /healthz tolerates either way but matching production headers
+        # surfaces auth-style 401s correctly during the doctor run.
+        req = urllib_request.Request(
+            url,
+            headers={"Origin": os.environ.get("PLATFORM_URL", "").rstrip("/")},
+        )
+        with urllib_request.urlopen(req, timeout=timeout) as resp:
+            return resp.status, None
+    except URLError as e:
+        return None, str(e.reason if hasattr(e, "reason") else e)
+    except Exception as e:
+        return None, str(e)
+
+
+def check_platform_health() -> Verdict:
+    label = "Platform reachability"
+    base = os.environ.get("PLATFORM_URL", "").strip().rstrip("/")
+    if not base:
+        _warn(label, "skipped (PLATFORM_URL unset — see Env vars)", "set PLATFORM_URL first")
+        return "warn"
+    if not base.startswith(("http://", "https://")):
+        _fail(
+            label,
+            f"PLATFORM_URL missing scheme: {base!r}",
+            "set PLATFORM_URL to include https:// — e.g. "
+            "PLATFORM_URL=https://your-tenant.staging.moleculesai.app",
+        )
+        return "fail"
+    if base.endswith("/"):
+        _warn(
+            label,
+            "PLATFORM_URL has trailing slash (will be stripped automatically)",
+            "remove the trailing slash to match the snippet shape",
+        )
+    status, err = _http_get(f"{base}/healthz")
+    if status is None:
+        _fail(label, f"GET {base}/healthz failed: {err}", "check DNS + firewall + scheme")
+        return "fail"
+    if not (200 <= status < 300):
+        _fail(label, f"GET {base}/healthz returned HTTP {status}", "verify the tenant subdomain is correct + provisioned")
+        return "fail"
+    _ok(label, f"GET {base}/healthz → {status}")
+    return "ok"
+
+
+def check_token_auth() -> Verdict:
+    """Light auth check via POST /registry/heartbeat.
+
+    Why heartbeat and not register: register is an UPSERT — sending
+    it from doctor would clobber the workspace's actual agent_card
+    (name, description, version) until the real agent next calls
+    register. That's an invisible production-disruption: someone
+    runs ``molecule-mcp doctor`` against a live workspace and the
+    canvas briefly displays "doctor-probe" as the agent name.
+
+    Heartbeat only updates last_heartbeat_at (and clears
+    awaiting_agent if needed) — that's exactly what a normal
+    molecule-mcp boot does every 20s, so an extra heartbeat from
+    the doctor is indistinguishable from background traffic.
+
+    Skipped when env vars failed earlier so the operator isn't shown
+    a redundant 401.
+    """
+    label = "Token auth"
+    base = os.environ.get("PLATFORM_URL", "").strip().rstrip("/")
+    workspace_id = os.environ.get("WORKSPACE_ID", "").strip()
+    token, source_label = _resolve_token()
+    if not (base and workspace_id and token):
+        _warn(label, "skipped (Env vars must pass first)", "fix Env vars, re-run")
+        return "warn"
+    import json
+    body = json.dumps({"id": workspace_id}).encode()
+    req = urllib_request.Request(
+        f"{base}/registry/heartbeat",
+        data=body,
+        method="POST",
+        headers={
+            "Authorization": f"Bearer {token}",
+            "Content-Type": "application/json",
+            "Origin": base,
+        },
+    )
+    try:
+        with urllib_request.urlopen(req, timeout=8.0) as resp:
+            status = resp.status
+    except URLError as e:
+        # Pull HTTP code from HTTPError; transport errors don't have one.
+        status = getattr(e, "code", None)
+        err = str(e.reason if hasattr(e, "reason") else e)
+        if status is None:
+            _fail(label, f"POST {base}/registry/heartbeat failed: {err}", "check network")
+            return "fail"
+    except Exception as e:
+        _fail(label, f"POST heartbeat failed: {e}", "check network")
+        return "fail"
+    if status == 401:
+        _fail(
+            label,
+            "401 Unauthorized — token rejected",
+            "tokens are shown only once at workspace-create time; "
+            "re-create the workspace OR rotate via canvas Tokens tab.",
+        )
+        return "fail"
+    if status == 404:
+        _fail(
+            label,
+            f"404 — workspace_id {workspace_id} not found on {base}",
+            "verify WORKSPACE_ID matches a real workspace + the tenant "
+            "subdomain in PLATFORM_URL.",
+        )
+        return "fail"
+    if not (200 <= status < 300):
+        _fail(label, f"POST heartbeat returned HTTP {status}", "see platform logs")
+        return "fail"
+    _ok(label, f"POST {base}/registry/heartbeat → {status} (token from {source_label})")
+    return "ok"
+
+
+# Back-compat alias: the previous name was check_register, but the
+# implementation switched to a non-mutating heartbeat probe (see
+# check_token_auth's docstring). Kept so external test suites or
+# pinned-import scripts don't break on the rename.
+check_register = check_token_auth
+
+
+CHECKS = [
+    check_python_version,
+    check_wheel_install,
+    check_path_for_binary,
+    check_env_vars,
+    check_platform_health,
+    check_token_auth,
+]
+
+
+def run() -> int:
+    """Run all checks and return a process exit code (0 ok, 1 if any fail)."""
+    print("molecule-mcp doctor — onboarding diagnostic")
+    print()
+    verdicts = []
+    for chk in CHECKS:
+        try:
+            verdicts.append(chk())
+        except Exception as e:
+            # A buggy check shouldn't kill the rest of the doctor run.
+            print(f"  [BUG]  {chk.__name__}: unexpected {type(e).__name__}: {e}")
+            verdicts.append("fail")
+    print()
+    fails = sum(1 for v in verdicts if v == "fail")
+    warns = sum(1 for v in verdicts if v == "warn")
+    if fails:
+        print(f"{fails} check(s) failed, {warns} warning(s). Fix the FAIL items above and re-run.")
+        return 1
+    if warns:
+        print(f"All required checks passed; {warns} warning(s) — review the next-step hints.")
+        return 0
+    print("All checks passed.")
+    return 0
diff --git a/workspace/tests/test_a2a_client.py b/workspace/tests/test_a2a_client.py
index f667ed95..068fbffd 100644
--- a/workspace/tests/test_a2a_client.py
+++ b/workspace/tests/test_a2a_client.py
@@ -273,6 +273,87 @@ class TestSendA2AMessage:
         assert _TEST_PEER_ID in result
         assert "/workspaces/" in result and "/a2a" in result
 
+    async def test_poll_queued_envelope_returns_success_string(self):
+        """Issue #2967: workspace-server's poll-mode short-circuit returns
+        {status:"queued", delivery_mode:"poll", method:...} when the peer
+        has no URL to dispatch to. Pre-fix the bare send_a2a_message parser
+        only knew about JSON-RPC {result, error} keys, so this fell through
+        to the 'unexpected response shape' error path → callers retried,
+        peer got duplicate delegations.
+
+        Pin: poll-queued envelope returns a clean success string that does
+        NOT start with _A2A_ERROR_PREFIX, so callers route it through the
+        normal-outcome path. Verified discriminating: assert_NOT_startswith
+        the error prefix would FAIL on the old code (which returned an
+        error-prefixed string) and PASSES on the new code.
+        """
+        import a2a_client
+
+        resp = _make_response(200, {
+            "status": "queued",
+            "delivery_mode": "poll",
+            "method": "message/send",
+        })
+        mock_client = _make_mock_client(post_resp=resp)
+
+        with patch("a2a_client.httpx.AsyncClient", return_value=mock_client):
+            result = await a2a_client.send_a2a_message(_TEST_PEER_ID, "task")
+
+        # Discriminating: pre-fix returned a string that startswith
+        # _A2A_ERROR_PREFIX, so this assertion would have FAILED on the
+        # old code. New code returns a queued-success string.
+        assert not result.startswith(a2a_client._A2A_ERROR_PREFIX), (
+            f"poll-queued envelope must not be tagged as A2A error; got: {result!r}"
+        )
+        assert "queued" in result.lower()
+        assert "poll" in result.lower()
+        # The method is included so a structured-log scraper can route by
+        # protocol verb if needed.
+        assert "message/send" in result
+
+    async def test_poll_queued_envelope_with_other_method(self):
+        """Same envelope but a different a2a_method (the future could add
+        message/sendStream or similar). Pin that the parser doesn't hardcode
+        message/send — whatever method the server echoed is preserved.
+        """
+        import a2a_client
+
+        resp = _make_response(200, {
+            "status": "queued",
+            "delivery_mode": "poll",
+            "method": "message/sendStream",
+        })
+        mock_client = _make_mock_client(post_resp=resp)
+
+        with patch("a2a_client.httpx.AsyncClient", return_value=mock_client):
+            result = await a2a_client.send_a2a_message(_TEST_PEER_ID, "task")
+
+        assert not result.startswith(a2a_client._A2A_ERROR_PREFIX)
+        assert "message/sendStream" in result
+
+    async def test_status_queued_without_poll_mode_still_falls_through(self):
+        """Defensive: only the {status:"queued", delivery_mode:"poll"} pair
+        triggers the queued-success branch. A response with status:"queued"
+        but a different delivery_mode (or none) is still 'unexpected' —
+        we don't want to silently swallow a future server bug that emits
+        a partial envelope. Pin both keys are required.
+        """
+        import a2a_client
+
+        resp = _make_response(200, {
+            "status": "queued",
+            # delivery_mode missing
+            "method": "message/send",
+        })
+        mock_client = _make_mock_client(post_resp=resp)
+
+        with patch("a2a_client.httpx.AsyncClient", return_value=mock_client):
+            result = await a2a_client.send_a2a_message(_TEST_PEER_ID, "task")
+
+        # Falls through — must STILL be tagged as error.
+        assert result.startswith(a2a_client._A2A_ERROR_PREFIX)
+        assert "unexpected response shape" in result
+
     async def test_exception_returns_error_prefix_and_message(self):
         """Network exception → returns _A2A_ERROR_PREFIX + exception text."""
         import a2a_client
diff --git a/workspace/tests/test_mcp_doctor.py b/workspace/tests/test_mcp_doctor.py
new file mode 100644
index 00000000..5b587d24
--- /dev/null
+++ b/workspace/tests/test_mcp_doctor.py
@@ -0,0 +1,198 @@
+"""Tests for the molecule-mcp doctor subcommand (#2934 item 6).
+
+Each `check_*` function is unit-tested in isolation via env
+manipulation. The integration test (`test_run_no_env_returns_1`) pins
+the end-to-end exit code on a stripped environment — what an operator
+running the command for the first time on an untouched shell sees.
+"""
+from __future__ import annotations
+
+import os
+import sys
+from pathlib import Path
+from unittest import mock
+
+import pytest
+
+# Workspace tests run from the workspace/ directory; mcp_doctor is
+# imported with the same `import mcp_doctor` shape as the rest of
+# the runtime (per pyproject's package layout).
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
+import mcp_doctor  # noqa: E402
+
+
+def test_module_exposes_six_checks():
+    """The doctor's checklist is six items today. Pin the count so
+    a future PR that drops a check (e.g. silently merges two) gets
+    flagged in review.
+    """
+    assert len(mcp_doctor.CHECKS) == 6
+
+
+def test_check_python_version_passes_on_311_plus():
+    """Pin the floor at 3.11 (matches the wheel's requires_python)."""
+    with mock.patch.object(sys, "version_info", (3, 11, 0, "final", 0)):
+        assert mcp_doctor.check_python_version() == "ok"
+    with mock.patch.object(sys, "version_info", (3, 12, 5, "final", 0)):
+        assert mcp_doctor.check_python_version() == "ok"
+
+
+def test_check_python_version_fails_on_310():
+    """3.10 is below the wheel's >=3.11 floor — must FAIL, not WARN.
+    pip silently filters the wheel out on 3.10 with `from versions:
+    none`, which reads as "package missing" — operators have spent
+    45min chasing that. The doctor's job is to call this out
+    explicitly.
+    """
+    with mock.patch.object(sys, "version_info", (3, 10, 12, "final", 0)):
+        assert mcp_doctor.check_python_version() == "fail"
+
+
+def test_check_env_vars_fails_when_all_unset(monkeypatch):
+    monkeypatch.delenv("PLATFORM_URL", raising=False)
+    monkeypatch.delenv("WORKSPACE_ID", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACES", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN_FILE", raising=False)
+    assert mcp_doctor.check_env_vars() == "fail"
+
+
+def test_check_env_vars_passes_with_token_env(monkeypatch):
+    monkeypatch.setenv("PLATFORM_URL", "https://x.moleculesai.app")
+    monkeypatch.setenv("WORKSPACE_ID", "ws-test")
+    monkeypatch.setenv("MOLECULE_WORKSPACE_TOKEN", "tok-abc")
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN_FILE", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACES", raising=False)
+    assert mcp_doctor.check_env_vars() == "ok"
+
+
+def test_check_env_vars_passes_with_token_file(monkeypatch, tmp_path):
+    """Ryan #2934 item 3 fix: token from a file (or keychain shim)
+    instead of inline env var so secrets stay out of shell history.
+    The doctor must accept that path equally with the inline form.
+    """
+    token_path = tmp_path / "token"
+    token_path.write_text("tok-from-file")
+    monkeypatch.setenv("PLATFORM_URL", "https://x.moleculesai.app")
+    monkeypatch.setenv("WORKSPACE_ID", "ws-test")
+    monkeypatch.setenv("MOLECULE_WORKSPACE_TOKEN_FILE", str(token_path))
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACES", raising=False)
+    assert mcp_doctor.check_env_vars() == "ok"
+
+
+def test_check_platform_health_warns_when_url_unset(monkeypatch):
+    monkeypatch.delenv("PLATFORM_URL", raising=False)
+    assert mcp_doctor.check_platform_health() == "warn"
+
+
+def test_check_platform_health_fails_on_missing_scheme(monkeypatch):
+    """A bare hostname is the second-most-common config error after
+    missing-token (per the snippet's NOTE on Origin/PLATFORM_URL).
+    The error message must say 'missing scheme' — not 'DNS error' —
+    so the operator can diagnose without inspecting the URL string.
+    """
+    monkeypatch.setenv("PLATFORM_URL", "x.moleculesai.app")
+    assert mcp_doctor.check_platform_health() == "fail"
+
+
+def test_check_register_skipped_without_env(monkeypatch):
+    monkeypatch.delenv("PLATFORM_URL", raising=False)
+    monkeypatch.delenv("WORKSPACE_ID", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN", raising=False)
+    # Skipped (warn), NOT failed — failing here would double-count
+    # the env-vars failure noise.
+    assert mcp_doctor.check_register() == "warn"
+
+
+def test_check_token_auth_uses_heartbeat_endpoint(monkeypatch):
+    """Pin: doctor MUST hit /registry/heartbeat, not /registry/register.
+
+    register is an UPSERT — using it from doctor would clobber the
+    workspace's actual agent_card metadata until the real agent next
+    calls register. heartbeat only updates last_heartbeat_at, which
+    a normal molecule-mcp boot does every 20s anyway, so the doctor's
+    extra heartbeat is indistinguishable from background traffic.
+
+    This test pins the URL via a urllib mock so a future refactor
+    that accidentally re-routes through /registry/register fails
+    here at PR-review time, not after operators report
+    "doctor-probe" briefly appearing as their agent name in canvas.
+    """
+    monkeypatch.setenv("PLATFORM_URL", "https://x.moleculesai.app")
+    monkeypatch.setenv("WORKSPACE_ID", "ws-test")
+    monkeypatch.setenv("MOLECULE_WORKSPACE_TOKEN", "tok-abc")
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN_FILE", raising=False)
+
+    captured: dict[str, object] = {}
+
+    class _FakeResp:
+        status = 200
+        def __enter__(self): return self
+        def __exit__(self, *a): pass
+
+    def fake_urlopen(req, timeout=None):
+        captured["full_url"] = req.full_url
+        captured["method"] = req.get_method()
+        return _FakeResp()
+
+    monkeypatch.setattr(mcp_doctor.urllib_request, "urlopen", fake_urlopen)
+    verdict = mcp_doctor.check_token_auth()
+    assert verdict == "ok"
+    assert captured["method"] == "POST"
+    # The load-bearing assertion — must use heartbeat, never register.
+    assert captured["full_url"].endswith("/registry/heartbeat"), (
+        f"doctor must use /registry/heartbeat (idempotent), not register "
+        f"(UPSERT — clobbers agent_card). Got: {captured['full_url']}"
+    )
+    assert "/registry/register" not in str(captured["full_url"]), (
+        "doctor must NEVER POST to /registry/register — that's a UPSERT "
+        "that overwrites agent_card metadata until the real agent next "
+        "calls register."
+    )
+
+
+def test_resolve_token_returns_value_and_label_for_env(monkeypatch):
+    """The single resolver returns both the value (for Bearer header)
+    and a non-secret label (for the env-vars summary). Drift between
+    label and value is the previous bug shape."""
+    monkeypatch.setenv("PLATFORM_URL", "https://x.moleculesai.app")
+    monkeypatch.setenv("MOLECULE_WORKSPACE_TOKEN", "secret-tok-abc")
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN_FILE", raising=False)
+    val, label = mcp_doctor._resolve_token()
+    assert val == "secret-tok-abc"
+    assert label == "env MOLECULE_WORKSPACE_TOKEN"
+    # Summary helper must agree with the resolver's source.
+    assert mcp_doctor._resolve_token_summary() == label
+
+
+def test_resolve_token_returns_none_when_missing(monkeypatch):
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN", raising=False)
+    monkeypatch.delenv("MOLECULE_WORKSPACE_TOKEN_FILE", raising=False)
+    val, label = mcp_doctor._resolve_token()
+    assert val is None
+    assert label is None
+
+
+def test_run_returns_1_when_any_fail(monkeypatch, capsys):
+    """End-to-end: stripped environment → at least one FAIL →
+    exit 1. Pin the exit-code contract so this is scriptable from
+    CI / install-checks too.
+    """
+    for k in (
+        "PLATFORM_URL",
+        "WORKSPACE_ID",
+        "MOLECULE_WORKSPACES",
+        "MOLECULE_WORKSPACE_TOKEN",
+        "MOLECULE_WORKSPACE_TOKEN_FILE",
+    ):
+        monkeypatch.delenv(k, raising=False)
+    code = mcp_doctor.run()
+    out = capsys.readouterr().out
+    assert code == 1
+    # The summary line must mention at least one failure count so
+    # an automated wrapper can grep for it.
+    assert "check(s) failed" in out
+    # And the human-facing label must be present so someone reading
+    # CI logs sees what the section is about, not a wall of [FAIL].
+    assert "molecule-mcp doctor" in out