diff --git a/src/main/runtime/orca-runtime-tests/worktree-ps-structured-host.spec.ts b/src/main/runtime/orca-runtime-tests/worktree-ps-structured-host.spec.ts
new file mode 100644
index 00000000000..58e7de1b674
--- /dev/null
+++ b/src/main/runtime/orca-runtime-tests/worktree-ps-structured-host.spec.ts
@@ -0,0 +1,146 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+import { OrcaRuntimeService } from '../orca-runtime-test-mocks.spec'
+import { TEST_WORKTREE_ID, store } from '../orca-runtime-test-fixtures.spec'
+import type { AgentJournalRenderItem } from '../../../shared/agent-session-journal-types'
+import type {
+  AgentSessionStatusEvent,
+  AgentSessionStatusSummary
+} from '../../../shared/agent-session-wire'
+import type { AgentSessionJournal } from '../../native-chat/agent-session-journal/journal-store'
+import type { StructuredAgentSessionHost } from '../../native-chat/agent-session-wire/structured-agent-session-host'
+import {
+  getStructuredAgentSessionHost,
+  setStructuredAgentSessionHost
+} from '../../native-chat/agent-session-wire/structured-agent-session-registry'
+import { StructuredAgentSessionStatusFeed } from '../../native-chat/agent-session-wire/structured-agent-session-status-feed'
+
+/**
+ * The production wiring, not the projection. Both structured-row suites call
+ * `attachRuntimeWorktreeAgentRows` directly with summaries they built themselves, so nothing
+ * executed `getWorktreePs`'s own `getStructuredAgentSessionHost()?.liveSessionStatusSummaries()`
+ * — and that file carries `@ts-nocheck`, so renaming the accessor stayed green in typecheck AND
+ * in the suite while `orca worktree ps` and mobile's poll would throw for every user.
+ */
+
+const HELD_SESSION = 'a1b2c3d4-e5f6-4a7b-8c9d-0e1f2a3b4c5d'
+const FORGOTTEN_SESSION = 'b2c3d4e5-f6a7-4b8c-9d0e-1f2a3b4c5d6e'
+const OBSERVED_AT = 1_757_030_400_000
+
+function runningTurn(prompt: string): AgentJournalRenderItem[] {
+  return [
+    {
+      itemId: 'user-1',
+      sequence: 1,
+      revision: 1,
+      observedAt: OBSERVED_AT,
+      body: { kind: 'message', role: 'user', blocks: [{ type: 'text', text: prompt }] }
+    },
+    {
+      itemId: 'turn-1',
+      sequence: 2,
+      revision: 1,
+      observedAt: OBSERVED_AT,
+      body: {
+        kind: 'status',
+        text: 'Working',
+        turnLifecycle: { turnId: 'turn-1', state: 'running' }
+      }
+    }
+  ]
+}
+
+function journalWith(prompt: string): AgentSessionJournal {
+  return {
+    isReadOnly: false,
+    lastActivityAt: () => OBSERVED_AT,
+    snapshot: () => ({ items: runningTurn(prompt) })
+  } as unknown as AgentSessionJournal
+}
+
+/** A real feed the host still holds one session on, having forgotten the other. Its `published`
+ *  cache never retracts, so the two views genuinely differ. */
+function statusFeed(): StructuredAgentSessionStatusFeed {
+  const session = (prompt: string) => ({
+    journal: journalWith(prompt),
+    params: { location: { workspaceId: TEST_WORKTREE_ID }, provider: 'claude' as const }
+  })
+  const sessions = new Map([
+    [HELD_SESSION, session('ship the thing')],
+    [FORGOTTEN_SESSION, session('rm the branch')]
+  ])
+  const feed = new StructuredAgentSessionStatusFeed({
+    sessions,
+    getRecord: () => null,
+    now: () => OBSERVED_AT
+  })
+  feed.publish(HELD_SESSION)
+  feed.publish(FORGOTTEN_SESSION)
+  // `forget-session`, the last eviction step, drops the session and leaves the feed alone.
+  sessions.delete(FORGOTTEN_SESSION)
+  return feed
+}
+
+/** Everything the feed retained, read through the snapshot a subscriber opens on. No production
+ *  code reads this; it is here so swapping the call site back to a whole-cache read is a one-line
+ *  edit that this suite must catch. */
+function retainedSummaries(feed: StructuredAgentSessionStatusFeed): AgentSessionStatusSummary[] {
+  let retained: AgentSessionStatusSummary[] = []
+  feed.subscribe({
+    id: 'retained-probe',
+    emit: (event: AgentSessionStatusEvent) => {
+      if (event.type === 'snapshot') {
+        retained = event.sessions
+      }
+    }
+  })()
+  return retained
+}
+
+function installHost(feed: StructuredAgentSessionStatusFeed) {
+  const liveSessionStatusSummaries = vi.fn(() => feed.liveSessionSummaries())
+  const retainedSessionStatusSummaries = vi.fn(() => retainedSummaries(feed))
+  // Typed against the real host, so renaming the accessor on the class reddens `tc` here — the
+  // caller cannot, because `orca-runtime-get-worktree-ps.ts` is `@ts-nocheck`.
+  const host: Pick<StructuredAgentSessionHost, 'liveSessionStatusSummaries'> & {
+    retainedSessionStatusSummaries: () => AgentSessionStatusSummary[]
+  } = { liveSessionStatusSummaries, retainedSessionStatusSummaries }
+  setStructuredAgentSessionHost(host as unknown as StructuredAgentSessionHost)
+  return { liveSessionStatusSummaries, retainedSessionStatusSummaries }
+}
+
+describe('worktree ps reads the installed structured host', () => {
+  afterEach(() => {
+    setStructuredAgentSessionHost(null)
+  })
+
+  it('reports the held session and asks the host for its live summaries', async () => {
+    const feed = statusFeed()
+    const { liveSessionStatusSummaries } = installHost(feed)
+
+    const { worktrees } = await new OrcaRuntimeService(store).getWorktreePs()
+
+    const worktree = worktrees.find((entry) => entry.worktreeId === TEST_WORKTREE_ID)
+    expect(worktree).toBeDefined()
+    // Exactly one: the forgotten session is still in the feed's retained cache, so a call site
+    // that enumerated that cache instead would report two.
+    expect(worktree?.agents).toHaveLength(1)
+    expect(worktree?.agents[0]).toMatchObject({
+      state: 'working',
+      agentType: 'claude',
+      prompt: 'ship the thing'
+    })
+    // Pins the call site to the live-intersecting accessor, not merely to some accessor.
+    expect(liveSessionStatusSummaries).toHaveBeenCalledTimes(1)
+  })
+
+  it('succeeds with no structured rows when no host is installed', async () => {
+    // Guard the guard: these specs share one module registry, so state the premise.
+    expect(getStructuredAgentSessionHost()).toBeNull()
+
+    const { worktrees } = await new OrcaRuntimeService(store).getWorktreePs()
+
+    const worktree = worktrees.find((entry) => entry.worktreeId === TEST_WORKTREE_ID)
+    expect(worktree).toBeDefined()
+    expect(worktree?.agents).toEqual([])
+  })
+})
diff --git a/src/main/runtime/orca-runtime.test.ts b/src/main/runtime/orca-runtime.test.ts
index 829c2ca321e..74098040c27 100644
--- a/src/main/runtime/orca-runtime.test.ts
+++ b/src/main/runtime/orca-runtime.test.ts
@@ -85,6 +85,7 @@ await import('./orca-runtime-tests/mobile-summaries.spec')
 await import('./orca-runtime-tests/mobile-summaries-part-02.spec')
 await import('./orca-runtime-tests/mobile-summaries-part-03.spec')
 await import('./orca-runtime-tests/mobile-summaries-part-04.spec')
+await import('./orca-runtime-tests/worktree-ps-structured-host.spec')
 await import('./orca-runtime-tests/terminal-sleep-and-teardown.spec')
 await import('./orca-runtime-tests/terminal-sleep-and-teardown-part-02.spec')
 await import('./orca-runtime-tests/terminal-sleep-and-teardown-part-03.spec')