diff --git a/canvas/src/components/BatchActionBar.tsx b/canvas/src/components/BatchActionBar.tsx
index 3a25c33b3..773ce9dae 100644
--- a/canvas/src/components/BatchActionBar.tsx
+++ b/canvas/src/components/BatchActionBar.tsx
@@ -149,7 +149,7 @@ export function BatchActionBar() {
         title="Clear selection (Escape)"
         className="p-1.5 rounded-lg text-[12px] text-ink-mid hover:text-ink hover:bg-surface-card/50 transition-colors disabled:opacity-50 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent/50"
       >
-        ✕
+        <span aria-hidden="true">✕</span>
       </button>
     </div>
   );
diff --git a/canvas/src/components/CommunicationOverlay.tsx b/canvas/src/components/CommunicationOverlay.tsx
index 11198d21e..80b111b0b 100644
--- a/canvas/src/components/CommunicationOverlay.tsx
+++ b/canvas/src/components/CommunicationOverlay.tsx
@@ -217,7 +217,11 @@ export function CommunicationOverlay() {
   }
 
   return (
-    <div className="fixed top-16 right-4 z-30 w-[320px] max-h-[400px] bg-surface-sunken/95 border border-line/50 rounded-xl shadow-xl shadow-black/30 backdrop-blur-sm overflow-hidden">
+    <div
+      role="complementary"
+      aria-label={`Communications panel — ${comms.length} message${comms.length !== 1 ? "s" : ""}`}
+      className="fixed top-16 right-4 z-30 w-[320px] max-h-[400px] bg-surface-sunken/95 border border-line/50 rounded-xl shadow-xl shadow-black/30 backdrop-blur-sm overflow-hidden"
+    >
       <div className="flex items-center justify-between px-3 py-2 border-b border-line/60">
         <div className="text-[10px] font-semibold text-ink-mid uppercase tracking-wider">
           <span aria-hidden="true">↗↙ </span>Communications ({comms.length})
diff --git a/canvas/src/components/ConversationTraceModal.tsx b/canvas/src/components/ConversationTraceModal.tsx
index 61a834c06..ccc874dde 100644
--- a/canvas/src/components/ConversationTraceModal.tsx
+++ b/canvas/src/components/ConversationTraceModal.tsx
@@ -125,7 +125,7 @@ export function ConversationTraceModal({ open, workspaceId: _workspaceId, onClos
                   aria-label="Close conversation trace"
                   className="text-ink-mid hover:text-ink-mid text-lg px-2 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-1 focus-visible:ring-offset-surface"
                 >
-                  ✕
+                  <span aria-hidden="true">✕</span>
                 </button>
               </Dialog.Close>
             </div>
diff --git a/canvas/src/components/OrgImportPreflightModal.tsx b/canvas/src/components/OrgImportPreflightModal.tsx
index 6bc4ea480..4b5f8b830 100644
--- a/canvas/src/components/OrgImportPreflightModal.tsx
+++ b/canvas/src/components/OrgImportPreflightModal.tsx
@@ -406,7 +406,7 @@ function StrictEnvRow({
         {envKey}
       </code>
       {configured ? (
-        <span className="text-[10px] text-good">✓ set</span>
+        <span aria-hidden="true" className="text-[10px] text-good">✓ set</span>
       ) : (
         <>
           <input
@@ -498,7 +498,7 @@ function AnyOfEnvGroup({
                 {m}
               </code>
               {isConfigured ? (
-                <span className="text-[10px] text-good">✓ set</span>
+                <span aria-hidden="true" className="text-[10px] text-good">✓ set</span>
               ) : (
                 <>
                   <input
diff --git a/canvas/src/components/WorkspaceNode.tsx b/canvas/src/components/WorkspaceNode.tsx
index 7999e216b..caf25d7de 100644
--- a/canvas/src/components/WorkspaceNode.tsx
+++ b/canvas/src/components/WorkspaceNode.tsx
@@ -323,7 +323,7 @@ export function WorkspaceNode({ id, data }: NodeProps<Node<WorkspaceNodeData>>)
             }}
             className="flex items-center gap-1.5 mt-1 w-full bg-accent/10 px-2 py-1 rounded-md border border-accent/40 hover:bg-accent/20 transition-colors text-left focus-visible:ring-2 focus-visible:ring-accent/70 focus-visible:outline-none"
           >
-            <span className="text-[10px] text-accent">↻</span>
+            <span aria-hidden="true" className="text-[10px] text-accent">↻</span>
             <span className="text-[10px] text-accent">Restart to apply changes</span>
           </button>
         )}
diff --git a/canvas/src/components/tabs/ActivityTab.tsx b/canvas/src/components/tabs/ActivityTab.tsx
index 092a58bc9..c34f1b8c5 100644
--- a/canvas/src/components/tabs/ActivityTab.tsx
+++ b/canvas/src/components/tabs/ActivityTab.tsx
@@ -145,7 +145,7 @@ export function ActivityTab({ workspaceId }: Props) {
                   : "text-ink-mid hover:text-ink-mid hover:bg-surface-card/60"
               }`}
             >
-              <span className="mr-0.5 opacity-60">{f.icon}</span> {f.label}
+              <span aria-hidden="true" className="mr-0.5 opacity-60">{f.icon}</span> {f.label}
             </button>
           ))}
           <div className="ml-auto flex items-center gap-2">
@@ -260,7 +260,7 @@ function ActivityRow({
             </span>
           )}
 
-          <span className={`text-[9px] ml-auto shrink-0 ${statusStyle.color}`}>
+          <span aria-hidden="true" className={`text-[9px] ml-auto shrink-0 ${statusStyle.color}`}>
             {statusStyle.icon}
           </span>
 
@@ -274,7 +274,7 @@ function ActivityRow({
             {formatTime(entry.created_at)}
           </span>
 
-          <span className="text-[9px] text-ink-mid">
+          <span aria-hidden="true" className="text-[9px] text-ink-mid">
             {expanded ? "▼" : "▶"}
           </span>
         </div>
diff --git a/canvas/src/components/tabs/ChatTab.tsx b/canvas/src/components/tabs/ChatTab.tsx
index d6a9b85ca..5aa1410e7 100644
--- a/canvas/src/components/tabs/ChatTab.tsx
+++ b/canvas/src/components/tabs/ChatTab.tsx
@@ -383,7 +383,7 @@ function MyChatPanel({ workspaceId, data }: Props) {
                 // ignore — user will see no change and can retry
               }
             }}
-            className="px-2 py-0.5 text-[10px] font-medium bg-accent/10 hover:bg-accent/20 text-accent rounded border border-accent/30 transition-colors shrink-0"
+            className="px-2 py-0.5 text-[10px] font-medium bg-accent/10 hover:bg-accent/20 text-accent rounded border border-accent/30 transition-colors shrink-0 focus:outline-none focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-1 focus-visible:ring-offset-zinc-900"
           >
             Enable
           </button>
@@ -582,7 +582,7 @@ function MyChatPanel({ workspaceId, data }: Props) {
                 <div className="mt-1.5 text-[9px] text-ink-mid space-y-0.5">
                   <div className="text-ink-mid">Processing with {runtimeDisplayName(data.runtime)}...</div>
                   {activityLog.map((line, i) => (
-                    <div key={line + i} className="pl-2 border-l border-line">◇ {line}</div>
+                    <div key={line + i} className="pl-2 border-l border-line"><span aria-hidden="true">◇</span> {line}</div>
                   ))}
                 </div>
               )}
diff --git a/canvas/src/components/tabs/FilesTab/FileEditor.tsx b/canvas/src/components/tabs/FilesTab/FileEditor.tsx
index db5301c5d..e757c41e2 100644
--- a/canvas/src/components/tabs/FilesTab/FileEditor.tsx
+++ b/canvas/src/components/tabs/FilesTab/FileEditor.tsx
@@ -35,7 +35,7 @@ export function FileEditor({
     return (
       <div className="flex-1 flex items-center justify-center">
         <div className="text-center">
-          <div className="text-2xl opacity-20 mb-2">📄</div>
+          <div aria-hidden="true" className="text-2xl opacity-20 mb-2">📄</div>
           <p className="text-[10px] text-ink-mid">Select a file to edit</p>
         </div>
       </div>
@@ -47,7 +47,7 @@ export function FileEditor({
       {/* File header */}
       <div className="flex items-center justify-between px-3 py-1.5 border-b border-line/40 bg-surface-sunken/20">
         <div className="flex items-center gap-1.5 min-w-0">
-          <span className="text-[10px] opacity-50">{getIcon(selectedFile, false)}</span>
+          <span aria-hidden="true" className="text-[10px] opacity-50">{getIcon(selectedFile, false)}</span>
           <span className="text-[10px] font-mono text-ink-mid truncate">{selectedFile}</span>
           {isDirty && <span className="text-[9px] text-warm">modified</span>}
         </div>
diff --git a/canvas/src/components/tabs/FilesTab/FileTree.tsx b/canvas/src/components/tabs/FilesTab/FileTree.tsx
index 0e32bc455..2c5800878 100644
--- a/canvas/src/components/tabs/FilesTab/FileTree.tsx
+++ b/canvas/src/components/tabs/FilesTab/FileTree.tsx
@@ -199,6 +199,9 @@ function TreeItem({
     return (
       <div>
         <div
+          role="button"
+          tabIndex={0}
+          aria-label={`${node.name}${isDropTarget ? " (drop target)" : ""}`}
           className={`group w-full flex items-center gap-1 px-2 py-0.5 text-left transition-colors cursor-pointer ${
             isDropTarget
               ? "bg-accent/20 outline outline-1 outline-accent/60"
@@ -206,11 +209,17 @@ function TreeItem({
           }`}
           style={{ paddingLeft: `${depth * 12 + 8}px` }}
           onClick={() => onToggleDir(node.path)}
+          onKeyDown={(e) => {
+            if (e.key === "Enter" || e.key === " ") {
+              e.preventDefault();
+              onToggleDir(node.path);
+            }
+          }}
           onContextMenu={(e) => openContextMenu(e, node)}
           {...dragProps}
         >
-          <span className="text-[9px] text-ink-mid w-3">{isLoading ? "…" : expanded ? "▼" : "▶"}</span>
-          <span className="text-[10px]">📁</span>
+          <span aria-hidden="true" className="text-[9px] text-ink-mid w-3">{isLoading ? "…" : expanded ? "▼" : "▶"}</span>
+          <span aria-hidden="true" className="text-[10px]">📁</span>
           <span className="text-[10px] text-ink-mid flex-1">{node.name}</span>
           <button
             aria-label={`Delete ${node.name}`}
@@ -244,14 +253,23 @@ function TreeItem({
 
   return (
     <div
+      role="button"
+      tabIndex={0}
+      aria-label={node.name}
       className={`group flex items-center gap-1 px-2 py-0.5 cursor-pointer transition-colors ${
         isSelected ? "bg-blue-900/30 text-ink" : "hover:bg-surface-card/40 text-ink-mid"
       }`}
       style={{ paddingLeft: `${depth * 12 + 20}px` }}
       onClick={() => onSelect(node.path)}
+      onKeyDown={(e) => {
+        if (e.key === "Enter" || e.key === " ") {
+          e.preventDefault();
+          onSelect(node.path);
+        }
+      }}
       onContextMenu={(e) => openContextMenu(e, node)}
     >
-      <span className="text-[9px]">{getIcon(node.name, false)}</span>
+      <span aria-hidden="true" className="text-[9px]">{getIcon(node.name, false)}</span>
       <span className="text-[10px] flex-1 truncate font-mono">{node.name}</span>
       <button
         aria-label={`Delete ${node.name}`}
diff --git a/canvas/src/components/tabs/MemoryTab.tsx b/canvas/src/components/tabs/MemoryTab.tsx
index 8e5608019..1602e2f99 100644
--- a/canvas/src/components/tabs/MemoryTab.tsx
+++ b/canvas/src/components/tabs/MemoryTab.tsx
@@ -368,7 +368,7 @@ export function MemoryTab({ workspaceId }: Props) {
                           TTL {new Date(entry.expires_at).toLocaleString()}
                         </span>
                       )}
-                      <span className="text-[10px] text-ink-mid">
+                      <span aria-hidden="true" className="text-[10px] text-ink-mid">
                         {expanded === entry.key ? "▼" : "▶"}
                       </span>
                     </div>
diff --git a/canvas/src/components/tabs/ScheduleTab.tsx b/canvas/src/components/tabs/ScheduleTab.tsx
index b25fbf1d6..f0af58709 100644
--- a/canvas/src/components/tabs/ScheduleTab.tsx
+++ b/canvas/src/components/tabs/ScheduleTab.tsx
@@ -313,7 +313,7 @@ export function ScheduleTab({ workspaceId }: Props) {
       <div className="flex-1 overflow-y-auto">
         {schedules.length === 0 && !showForm ? (
           <div className="p-6 text-center">
-            <div className="text-2xl mb-2">⏲</div>
+            <div aria-hidden="true" className="text-2xl mb-2">⏲</div>
             <div className="text-[10px] text-ink-mid mb-1">No schedules yet</div>
             <div className="text-[9px] text-ink-mid">
               Add a schedule to run tasks automatically — daily scans, periodic reports, standup reminders.
diff --git a/canvas/src/components/tabs/chat/AttachmentViews.tsx b/canvas/src/components/tabs/chat/AttachmentViews.tsx
index 0d01a425d..7a2a47ea2 100644
--- a/canvas/src/components/tabs/chat/AttachmentViews.tsx
+++ b/canvas/src/components/tabs/chat/AttachmentViews.tsx
@@ -33,7 +33,7 @@ export function PendingAttachmentPill({
       <button
         onClick={onRemove}
         aria-label={`Remove ${file.name}`}
-        className="ml-0.5 text-ink-mid hover:text-ink transition-colors shrink-0"
+        className="ml-0.5 text-ink-mid hover:text-ink transition-colors shrink-0 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-1"
       >
         <svg width="10" height="10" viewBox="0 0 16 16" fill="none" aria-hidden="true">
           <path d="M4 4l8 8M12 4l-8 8" stroke="currentColor" strokeWidth="1.6" strokeLinecap="round" />
@@ -63,7 +63,8 @@ export function AttachmentChip({
     <button
       onClick={() => onDownload(attachment)}
       title={`Download ${attachment.name}`}
-      className={`flex items-center gap-1.5 rounded-md border px-2 py-1 text-[10px] transition-colors max-w-full ${toneClasses}`}
+      aria-label={`Download ${attachment.name}`}
+      className={`flex items-center gap-1.5 rounded-md border px-2 py-1 text-[10px] transition-colors max-w-full focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-1 ${toneClasses}`}
     >
       <FileGlyph className="shrink-0 opacity-70" />
       <span className="truncate">{attachment.name}</span>