From 45d303efbaef480c9f11aff20d35763c9b4e8447 Mon Sep 17 00:00:00 2001
From: Merge Sim <sim@local>
Date: Mon, 31 Aug 2026 11:10:46 -0700
Subject: [PATCH] fix(runtime): fence diagnostics by shared-control capability

---
 .../runtime-status-diagnostics-generation.ts  |  4 ++-
 .../slices/runtime-status-diagnostics.test.ts | 32 +++++++++++++++++--
 ...-runtime-shared-control-connection.test.ts |  5 +++
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/renderer/src/store/slices/runtime-status-diagnostics-generation.ts b/src/renderer/src/store/slices/runtime-status-diagnostics-generation.ts
index 9e94cbc77c9..b6fabe7f49b 100644
--- a/src/renderer/src/store/slices/runtime-status-diagnostics-generation.ts
+++ b/src/renderer/src/store/slices/runtime-status-diagnostics-generation.ts
@@ -1,3 +1,5 @@
+import { REMOTE_RUNTIME_SHARED_CONTROL_CAPABILITY } from '../../../../shared/protocol-version'
+
 const diagnosticsGenerationByEnvironment = new Map<string, number>()
 
 export function acceptRuntimeEnvironmentDiagnosticsGeneration(
@@ -25,7 +27,7 @@ export function mergePushedRuntimeEnvironmentDiagnostics(args: {
 }): void {
   if (
     !acceptRuntimeEnvironmentDiagnosticsGeneration(args.environmentId, args.transportGeneration) ||
-    !args.current?.status
+    !args.current?.status?.capabilities?.includes(REMOTE_RUNTIME_SHARED_CONTROL_CAPABILITY)
   ) {
     return
   }
diff --git a/src/renderer/src/store/slices/runtime-status-diagnostics.test.ts b/src/renderer/src/store/slices/runtime-status-diagnostics.test.ts
index 29469ff6284..9faecdcabf1 100644
--- a/src/renderer/src/store/slices/runtime-status-diagnostics.test.ts
+++ b/src/renderer/src/store/slices/runtime-status-diagnostics.test.ts
@@ -1,5 +1,6 @@
 import { describe, expect, it } from 'vitest'
 import { create } from 'zustand'
+import { REMOTE_RUNTIME_SHARED_CONTROL_CAPABILITY } from '../../../../shared/protocol-version'
 import type { RuntimeStatus } from '../../../../shared/runtime-types'
 import { createRuntimeStatusSlice, type RuntimeStatusSlice } from './runtime-status'
 
@@ -27,7 +28,9 @@ function createSliceStore() {
 describe('runtime-status diagnostics', () => {
   it('merges transport diagnostics into the complete status and fences stale pushes', () => {
     const store = createSliceStore()
-    const status = makeStatus()
+    const status = makeStatus({
+      capabilities: ['browser.screencast.v1', REMOTE_RUNTIME_SHARED_CONTROL_CAPABILITY]
+    })
     store.getState().setRuntimeEnvironmentStatus('env-a', { status, checkedAt: 1 })
     const closed = {
       state: 'closed' as const,
@@ -45,7 +48,10 @@ describe('runtime-status diagnostics', () => {
     })
     expect(store.getState().runtimeStatusByEnvironmentId.get('env-a')?.status).toMatchObject({
       runtimeId: 'runtime-a',
-      capabilities: ['browser.screencast.v1'],
+      capabilities: expect.arrayContaining([
+        'browser.screencast.v1',
+        REMOTE_RUNTIME_SHARED_CONTROL_CAPABILITY
+      ]),
       liveTabCount: 3,
       remoteControl: closed
     })
@@ -58,4 +64,26 @@ describe('runtime-status diagnostics', () => {
       store.getState().runtimeStatusByEnvironmentId.get('env-a')?.status?.remoteControl?.state
     ).toBe('closed')
   })
+
+  it('ignores diagnostics after the latest status drops shared-control support', () => {
+    const store = createSliceStore()
+    const status = makeStatus({ capabilities: [] })
+    store.getState().setRuntimeEnvironmentStatus('env-a', { status, checkedAt: 1 })
+
+    store.getState().publishRuntimeEnvironmentDiagnostics({
+      environmentId: 'env-a',
+      transportGeneration: 3,
+      diagnostics: {
+        state: 'reconnecting',
+        pendingRequestCount: 0,
+        subscriptionCount: 1,
+        reconnectAttempt: 2,
+        lastConnectedAt: 1,
+        lastClose: { code: 1006, reason: 'network' },
+        lastError: 'connection lost'
+      }
+    })
+
+    expect(store.getState().runtimeStatusByEnvironmentId.get('env-a')?.status).toBe(status)
+  })
 })
diff --git a/src/shared/remote-runtime-shared-control-connection.test.ts b/src/shared/remote-runtime-shared-control-connection.test.ts
index 466dbf3c972..e55805725c4 100644
--- a/src/shared/remote-runtime-shared-control-connection.test.ts
+++ b/src/shared/remote-runtime-shared-control-connection.test.ts
@@ -32,11 +32,16 @@ describe('RemoteRuntimeSharedControlConnection', () => {
 
     expect(first).toMatchObject({ ok: true, result: { method: 'worktree.ps' } })
     expect(second).toMatchObject({ ok: true, result: { method: 'session.tabs.listAll' } })
+    expect(server.connectionCount()).toBe(1)
     expect(server.auths).toContainEqual({
       type: 'e2ee_auth',
       deviceToken: 'device-token',
       clientCapabilities: remoteRuntimeClientCapabilities()
     })
+    expect(server.requests.map((request) => request.method)).toEqual([
+      'worktree.ps',
+      'session.tabs.listAll'
+    ])
     expect((connection.close(), states)).toEqual(
       expect.arrayContaining(['awaiting_ready', 'ready', 'closed'])
     )