diff --git a/packages/app/src/pages/session/message-timeline.tsx b/packages/app/src/pages/session/message-timeline.tsx
index c6329b39c5..5385dd6c7a 100644
--- a/packages/app/src/pages/session/message-timeline.tsx
+++ b/packages/app/src/pages/session/message-timeline.tsx
@@ -73,6 +73,7 @@ import { useServer } from "@/context/server"
 import { usePrompt } from "@/context/prompt"
 import { startPrompt, draftPrompt } from "@/utils/start-prompt"
 import { amicodeGet } from "@/utils/amicode-fetch"
+import { inAmicode, postAmicode } from "@/pages/session/use-amicode-commands"
 import { useSync } from "@/context/sync"
 import { notifySessionTabsRemoved } from "@/components/titlebar-session-events"
 import { messageAgentColor } from "@/utils/agent"
@@ -1697,6 +1698,7 @@ export function MessageTimeline(props: {
               }
               onOpenEntity={openEntityView}
               onOpenSwitcher={openSwitcher}
+              onInspectRun={inAmicode() ? () => postAmicode("amicode.openInspector") : undefined}
               retryLabel={language.t("amicode.retry")}
               unavailableLabel={language.t("amicode.unavailable")}
               onAsk={(text) => {
diff --git a/packages/app/src/pages/session/use-amicode-commands.test.ts b/packages/app/src/pages/session/use-amicode-commands.test.ts
new file mode 100644
index 0000000000..602ba8d10c
--- /dev/null
+++ b/packages/app/src/pages/session/use-amicode-commands.test.ts
@@ -0,0 +1,44 @@
+import { describe, expect, spyOn, test } from "bun:test"
+import { inAmicode, postAmicode } from "./use-amicode-commands"
+
+// The "Inspect Run" button (entity rail) and the Amico command palette both
+// reach the VS Code extension through postAmicode(). chat_panel.ts relays the
+// envelope to the host and executes ONLY commands on its BRIDGE_ALLOWED_COMMANDS
+// allowlist — so the exact envelope shape and command string are a contract.
+describe("postAmicode bridge envelope", () => {
+  test('posts {source:"amicode", kind:"command", command} to window.parent with "*"', () => {
+    const spy = spyOn(window.parent, "postMessage").mockImplementation(() => {})
+    try {
+      postAmicode("amicode.openInspector")
+      expect(spy).toHaveBeenCalledTimes(1)
+      // Cast past the DOM postMessage overloads (which type arg 2 as
+      // WindowPostMessageOptions) — postAmicode passes a legacy string origin.
+      const [message, targetOrigin] = spy.mock.calls[0] as unknown as [unknown, unknown]
+      expect(message).toEqual({ source: "amicode", kind: "command", command: "amicode.openInspector" })
+      // Post to any origin — chat_panel.ts pins the origin on the receiving side.
+      expect(targetOrigin).toBe("*")
+    } finally {
+      spy.mockRestore()
+    }
+  })
+
+  test("never throws even if the parent frame rejects the post", () => {
+    const spy = spyOn(window.parent, "postMessage").mockImplementation(() => {
+      throw new Error("no parent")
+    })
+    try {
+      expect(() => postAmicode("amicode.openInspector")).not.toThrow()
+    } finally {
+      spy.mockRestore()
+    }
+  })
+})
+
+// inAmicode() gates the button (and the palette ops) so they never render in the
+// public web / share build, where there is no extension host to relay to. In a
+// non-framed context self === top, so it must report false.
+describe("inAmicode gate", () => {
+  test("false when not framed (self === top)", () => {
+    expect(inAmicode()).toBe(false)
+  })
+})
diff --git a/packages/app/src/pages/session/use-amicode-commands.tsx b/packages/app/src/pages/session/use-amicode-commands.tsx
index ebeee0f065..b9a072be9d 100644
--- a/packages/app/src/pages/session/use-amicode-commands.tsx
+++ b/packages/app/src/pages/session/use-amicode-commands.tsx
@@ -10,9 +10,12 @@ import { useCommand, type CommandOption } from "@/context/command"
 // Each command posts {source:"amicode",kind:"command",command} to window.parent;
 // chat_panel.ts relays it to an ALLOWLISTED vscode command.
 
-const inAmicode = () => typeof window !== "undefined" && window.self !== window.top
+// Exported so non-palette surfaces (e.g. the "Inspect Run" button on the entity
+// rail) can fire the same host-bridged commands. inAmicode() gates them out of
+// the public web/share build, where there is no extension host to relay to.
+export const inAmicode = () => typeof window !== "undefined" && window.self !== window.top
 
-const postAmicode = (command: string) => {
+export const postAmicode = (command: string) => {
   try {
     window.parent?.postMessage({ source: "amicode", kind: "command", command }, "*")
   } catch {}
diff --git a/packages/ui/src/amicode/entity-rail.tsx b/packages/ui/src/amicode/entity-rail.tsx
index c3c4e2b86a..3d82be9ad1 100644
--- a/packages/ui/src/amicode/entity-rail.tsx
+++ b/packages/ui/src/amicode/entity-rail.tsx
@@ -49,6 +49,10 @@ export function AmicodeEntityRail(props: {
   onOpenEntity: (kind: string, seq?: number) => void
   onOpenSwitcher: () => void
   onAsk?: (text: string) => void
+  // Bridge-agnostic: fired when the user clicks "Inspect Run". The app wires it
+  // to the host (postAmicode → amicode.openInspector) and passes it only when
+  // framed in Amicode, so the button stays hidden everywhere else.
+  onInspectRun?: () => void
   retryLabel: string
   unavailableLabel: string
 }) {
@@ -134,6 +138,12 @@ export function AmicodeEntityRail(props: {
     if (snapshot.kind !== "ready") return undefined
     return snapshot.view.name ?? snapshot.view.slug
   })
+  // Whether there is a run to inspect — gates the "Inspect Run" button so it
+  // appears alongside the live run chip, not before any solve has started.
+  const hasRun = createMemo(() => {
+    const snapshot = state()
+    return snapshot.kind === "ready" && snapshot.view.runs.length > 0
+  })
 
   return (
     <Show when={amicodeParts().any > 0}>
@@ -264,6 +274,30 @@ export function AmicodeEntityRail(props: {
               </Show>
             )}
           </For>
+          <Show when={props.onInspectRun && hasRun()}>
+            <button
+              type="button"
+              data-slot="amicode-rail-inspect"
+              style={{
+                display: "inline-flex",
+                "align-items": "center",
+                "flex-shrink": "0",
+                gap: "4px",
+                border: "1px solid var(--v2-border-border-base)",
+                "border-radius": "5px",
+                background: "none",
+                color: "var(--v2-text-text-accent)",
+                padding: "1px 8px",
+                font: "inherit",
+                "font-weight": "600",
+                cursor: "pointer",
+              }}
+              title="Open the Run Inspector panel"
+              onClick={() => props.onInspectRun?.()}
+            >
+              Inspect Run
+            </button>
+          </Show>
         </Show>
       </div>
     </Show>