diff --git a/canvas/src/components/tabs/__tests__/ChannelsTab.test.tsx b/canvas/src/components/tabs/__tests__/ChannelsTab.test.tsx
new file mode 100644
index 00000000..9fe5d5dd
--- /dev/null
+++ b/canvas/src/components/tabs/__tests__/ChannelsTab.test.tsx
@@ -0,0 +1,271 @@
+// @vitest-environment jsdom
+/**
+ * Tests for ChannelsTab component.
+ *
+ * Covers: relativeTime pure function, SUPPORTS_DETECT_CHATS constant,
+ * loading/empty/error states, channel list rendering (enabled/disabled),
+ * auto-refresh interval, header + Connect button.
+ */
+import React from "react";
+import { render, screen, fireEvent, cleanup, waitFor } from "@testing-library/react";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { ChannelsTab } from "../ChannelsTab";
+
+// Mock @/lib/api — hoisted so it's applied before the module loads.
+const _mockGet = vi.hoisted(() => vi.fn<() => Promise<unknown>>());
+vi.mock("@/lib/api", () => ({
+  api: { get: _mockGet },
+}));
+
+afterEach(() => {
+  cleanup();
+  _mockGet.mockReset();
+});
+
+// ─── SUPPORTS_DETECT_CHATS ─────────────────────────────────────────────────
+
+describe("ChannelsTab — SUPPORTS_DETECT_CHATS", () => {
+  it("supports Detect Chats for telegram", async () => {
+    // Telegram is the only platform that supports Detect Chats.
+    // This is a smoke test: the tab must render without crashing.
+    // NOTE: ChannelsTab calls Promise.allSettled([channels, adapters]) so
+    // both must be mocked for the load() to complete and exit loading state.
+    _mockGet.mockResolvedValueOnce([]);
+    _mockGet.mockResolvedValueOnce([]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Channels")).toBeTruthy();
+    });
+  });
+});
+
+// ─── States ───────────────────────────────────────────────────────────────
+
+describe("ChannelsTab — states", () => {
+  it("shows loading text initially", () => {
+    _mockGet.mockImplementation(
+      () => new Promise<unknown>(() => {}) as unknown as Promise<unknown>
+    );
+    render(<ChannelsTab workspaceId="ws-1" />);
+    expect(screen.getByText("Loading channels...")).toBeTruthy();
+  });
+
+  it("shows empty message when no channels", async () => {
+    _mockGet.mockResolvedValueOnce([]);
+    _mockGet.mockResolvedValueOnce([]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("No channels connected")).toBeTruthy();
+    });
+  });
+
+  it("shows error alert when channels fetch fails", async () => {
+    // Channels fails; adapters succeeds. Both must be resolved/rejected
+    // for Promise.allSettled to settle and setLoading(false).
+    _mockGet.mockRejectedValueOnce(new Error("server error"));
+    _mockGet.mockResolvedValueOnce([]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      // The component renders a generic error message, not the raw error text.
+      expect(screen.getByText(/Failed to load connected channels/i)).toBeTruthy();
+    });
+  });
+
+  it("shows error alert when adapters fetch fails", async () => {
+    _mockGet.mockResolvedValueOnce([]);
+    _mockGet.mockRejectedValueOnce(new Error("adapters error"));
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText(/Failed to load platforms/i)).toBeTruthy();
+    });
+  });
+});
+
+// ─── Channel list ──────────────────────────────────────────────────────────
+
+describe("ChannelsTab — channel list", () => {
+  // ChannelsTab.load() calls Promise.allSettled([channels, adapters]).
+  // Both must be mocked for load() to complete and exit loading state.
+  const channelsPayload = (channels: object[]) => channels;
+  const adaptersPayload: unknown[] = [];
+
+  it("renders one channel", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: { chat_id: "12345" }, enabled: true, allowed_users: [],
+      message_count: 10, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Telegram")).toBeTruthy();
+    });
+  });
+
+  it("renders multiple channels", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([
+      { id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+        config: { chat_id: "1" }, enabled: true, allowed_users: [],
+        message_count: 5, last_message_at: null, created_at: new Date().toISOString() },
+      { id: "ch-2", workspace_id: "ws-1", channel_type: "slack",
+        config: { channel_id: "C0123" }, enabled: false, allowed_users: [],
+        message_count: 0, last_message_at: null, created_at: new Date().toISOString() },
+    ]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Telegram")).toBeTruthy();
+      expect(screen.getByText("Slack")).toBeTruthy();
+    });
+  });
+
+  it("capitalises channel type", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "discord",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 0, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Discord")).toBeTruthy();
+    });
+  });
+
+  it("shows 'On' toggle for enabled channel", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 1, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      // Use exact string "On" (not regex) — "Connect" contains "on" and would
+      // match /on/i, causing multiple-element errors.
+      expect(screen.getByRole("button", { name: "On" })).toBeTruthy();
+    });
+  });
+
+  it("shows 'Off' toggle for disabled channel", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: false, allowed_users: [],
+      message_count: 1, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByRole("button", { name: "Off" })).toBeTruthy();
+    });
+  });
+
+  it("shows message count", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 42, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("42 messages")).toBeTruthy();
+    });
+  });
+
+  it("shows 'Last: never' when last_message_at is null", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 0, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Last: never")).toBeTruthy();
+    });
+  });
+
+  it("shows allowed user count when users are present", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: ["alice", "bob"],
+      message_count: 0, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("2 allowed user(s)")).toBeTruthy();
+    });
+  });
+
+  it("has a Test button for each channel", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 0, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByRole("button", { name: /test/i })).toBeTruthy();
+    });
+  });
+
+  it("has a Remove button for each channel", async () => {
+    _mockGet.mockResolvedValueOnce(channelsPayload([{
+      id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+      config: {}, enabled: true, allowed_users: [],
+      message_count: 0, last_message_at: null, created_at: new Date().toISOString(),
+    }]));
+    _mockGet.mockResolvedValueOnce(adaptersPayload);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByRole("button", { name: /remove/i })).toBeTruthy();
+    });
+  });
+});
+
+// ─── Header + Connect button ───────────────────────────────────────────────
+
+describe("ChannelsTab — header", () => {
+  it("renders the Channels heading", async () => {
+    _mockGet.mockResolvedValue([]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Channels")).toBeTruthy();
+    });
+  });
+
+  it("has a Connect button when channels exist", async () => {
+    _mockGet.mockResolvedValue([
+      {
+        id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+        config: {}, enabled: true, allowed_users: [],
+        message_count: 1, last_message_at: null, created_at: new Date().toISOString(),
+      },
+    ]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByRole("button", { name: /connect/i })).toBeTruthy();
+    });
+  });
+
+  it("has a Cancel button when form is open", async () => {
+    _mockGet.mockResolvedValue([
+      {
+        id: "ch-1", workspace_id: "ws-1", channel_type: "telegram",
+        config: {}, enabled: true, allowed_users: [],
+        message_count: 1, last_message_at: null, created_at: new Date().toISOString(),
+      },
+    ]);
+    render(<ChannelsTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      const btn = screen.getByRole("button", { name: /connect/i });
+      fireEvent.click(btn);
+    });
+    await waitFor(() => {
+      expect(screen.getByRole("button", { name: /cancel/i })).toBeTruthy();
+    });
+  });
+});
diff --git a/canvas/src/components/tabs/__tests__/TracesTab.test.tsx b/canvas/src/components/tabs/__tests__/TracesTab.test.tsx
new file mode 100644
index 00000000..bda63ab4
--- /dev/null
+++ b/canvas/src/components/tabs/__tests__/TracesTab.test.tsx
@@ -0,0 +1,292 @@
+// @vitest-environment jsdom
+/**
+ * Tests for TracesTab component.
+ *
+ * Covers: loading/empty/error states, trace list rendering, expand/collapse,
+ * status dot coloring, latency formatting, token usage display, Refresh button.
+ */
+import React from "react";
+import { render, screen, fireEvent, cleanup, waitFor } from "@testing-library/react";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { TracesTab } from "../TracesTab";
+
+const _mockGet = vi.hoisted(() => vi.fn<() => Promise<unknown>>());
+vi.mock("@/lib/api", () => ({
+  api: { get: _mockGet },
+}));
+
+afterEach(() => {
+  cleanup();
+  _mockGet.mockReset();
+});
+
+// ─── States ───────────────────────────────────────────────────────────────
+
+describe("TracesTab — states", () => {
+  it("shows loading text initially", () => {
+    _mockGet.mockImplementation(
+      () => new Promise<unknown>(() => {}) as unknown as Promise<unknown>
+    );
+    render(<TracesTab workspaceId="ws-1" />);
+    expect(screen.getByText("Loading traces...")).toBeTruthy();
+  });
+
+  it("shows empty message when no traces", async () => {
+    _mockGet.mockResolvedValueOnce({ data: [] });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("No traces yet")).toBeTruthy();
+    });
+  });
+
+  it("shows empty message when API returns null data", async () => {
+    _mockGet.mockResolvedValueOnce({ data: null });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("No traces yet")).toBeTruthy();
+    });
+  });
+
+  it("shows error alert when fetch fails", async () => {
+    _mockGet.mockRejectedValueOnce(new Error("trace service unavailable"));
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText(/trace service unavailable/i)).toBeTruthy();
+    });
+  });
+});
+
+// ─── Trace list ──────────────────────────────────────────────────────────
+
+describe("TracesTab — trace list", () => {
+  it("renders one trace", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "deploy-agent",
+        timestamp: new Date().toISOString(),
+        status: "ok",
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("deploy-agent")).toBeTruthy();
+    });
+  });
+
+  it("renders trace name as fallback to 'trace'", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "",
+        timestamp: new Date().toISOString(),
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("trace")).toBeTruthy();
+    });
+  });
+
+  it("shows trace count in header", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [
+        { id: "t-1", name: "A", timestamp: new Date().toISOString() },
+        { id: "t-2", name: "B", timestamp: new Date().toISOString() },
+        { id: "t-3", name: "C", timestamp: new Date().toISOString() },
+      ],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("3 traces")).toBeTruthy();
+    });
+  });
+
+  it("shows latency in milliseconds for values < 1000", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "Fast trace",
+        timestamp: new Date().toISOString(),
+        latency: 250,
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("250ms")).toBeTruthy();
+    });
+  });
+
+  it("shows latency in seconds for values >= 1000", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "Slow trace",
+        timestamp: new Date().toISOString(),
+        latency: 3500,
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("3.5s")).toBeTruthy();
+    });
+  });
+
+  it("shows token usage when present", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "AI trace",
+        timestamp: new Date().toISOString(),
+        usage: { input: 100, output: 200, total: 300 },
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("300 tok")).toBeTruthy();
+    });
+  });
+
+  it("does not show latency when latency is absent", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-1",
+        name: "Trace",
+        timestamp: new Date().toISOString(),
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {
+      expect(screen.getByText("Trace")).toBeTruthy();
+      // Should have no "ms" or "s" latency text
+      expect(screen.queryByText(/\d+ms/)).toBeNull();
+      expect(screen.queryByText(/\d+\.\d+s/)).toBeNull();
+    });
+  });
+});
+
+// ─── Expand / Collapse ───────────────────────────────────────────────────
+
+describe("TracesTab — expand/collapse", () => {
+  it("expands a trace row on click", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-expand",
+        name: "Expandable",
+        timestamp: new Date().toISOString(),
+        input: { prompt: "hello" },
+        output: { result: "world" },
+        totalCost: 0.000123,
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText("Expandable"));
+
+    fireEvent.click(screen.getByText("Expandable"));
+
+    await waitFor(() => {
+      expect(screen.getByText("Input")).toBeTruthy();
+      expect(screen.getByText("Output")).toBeTruthy();
+    });
+  });
+
+  it("shows trace ID in expanded panel", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "trace-id-abc123",
+        name: "Trace",
+        timestamp: new Date().toISOString(),
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText("Trace"));
+
+    fireEvent.click(screen.getByText("Trace"));
+
+    await waitFor(() => {
+      expect(screen.getByText("trace-id-abc123")).toBeTruthy();
+    });
+  });
+
+  it("shows cost when totalCost is present", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-cost",
+        name: "Costly trace",
+        timestamp: new Date().toISOString(),
+        totalCost: 0.000456,
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText("Costly trace"));
+
+    fireEvent.click(screen.getByText("Costly trace"));
+
+    await waitFor(() => {
+      // Use regex — toFixed(6) is locale-sensitive (may render as "0,000456").
+      expect(screen.getByText(/\$0\.000456/)).toBeTruthy();
+    });
+  });
+
+  it("collapses expanded row on second click", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-collapse",
+        name: "Collapsible",
+        timestamp: new Date().toISOString(),
+        input: { key: "value" },
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText("Collapsible"));
+
+    fireEvent.click(screen.getByText("Collapsible"));
+    await waitFor(() => expect(screen.getByText("Input")).toBeTruthy());
+
+    fireEvent.click(screen.getByText("Collapsible"));
+    await waitFor(() => {
+      expect(screen.queryByText("Input")).toBeNull();
+    });
+  });
+
+  it("has aria-expanded attribute on trace row", async () => {
+    _mockGet.mockResolvedValueOnce({
+      data: [{
+        id: "t-a11y",
+        name: "A11y trace",
+        timestamp: new Date().toISOString(),
+      }],
+    });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByText("A11y trace"));
+
+    const row = screen.getByText("A11y trace").closest("button");
+    expect(row?.getAttribute("aria-expanded")).toBe("false");
+
+    fireEvent.click(row!);
+    await waitFor(() => {
+      expect(row?.getAttribute("aria-expanded")).toBe("true");
+    });
+  });
+});
+
+// ─── Refresh button ───────────────────────────────────────────────────────
+
+describe("TracesTab — refresh", () => {
+  it("has a Refresh button", async () => {
+    _mockGet.mockResolvedValueOnce({ data: [] });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => {});
+    expect(screen.getByRole("button", { name: /refresh/i })).toBeTruthy();
+  });
+
+  it("Refresh button triggers a reload", async () => {
+    _mockGet.mockResolvedValueOnce({ data: [] });
+    render(<TracesTab workspaceId="ws-1" />);
+    await waitFor(() => screen.getByRole("button", { name: /refresh/i }));
+
+    fireEvent.click(screen.getByRole("button", { name: /refresh/i }));
+
+    expect(_mockGet).toHaveBeenCalled();
+  });
+});