diff --git a/src/cli/orchestration-mutation-recovery.test.ts b/src/cli/orchestration-mutation-recovery.test.ts
index 2acd3496241..c1870f5affe 100644
--- a/src/cli/orchestration-mutation-recovery.test.ts
+++ b/src/cli/orchestration-mutation-recovery.test.ts
@@ -1,5 +1,8 @@
 import { describe, expect, it } from 'vitest'
-import { orchestrationMutationRecoveryError } from './orchestration-mutation-recovery'
+import {
+  orchestrationMutationRecoveryError,
+  renderCommand
+} from './orchestration-mutation-recovery'
 import { RuntimeClientError } from './runtime-client'
 
 describe('orchestration mutation recovery', () => {
@@ -111,4 +114,27 @@ describe('orchestration mutation recovery', () => {
       'request_4'
     ])
   })
+
+  it('renders Windows cmd recovery guidance without quote drift or percent expansion', () => {
+    expect(
+      renderCommand(
+        ['orca', 'orchestration', 'worker-start', '--comment', 'literal "quoted" %PATH% & safe'],
+        'win32',
+        { ComSpec: 'C:\\Windows\\System32\\cmd.exe' }
+      )
+    ).toBe(
+      '"orca" "orchestration" "worker-start" "--comment" "literal ""quoted"" "^%"PATH"^%" & safe"'
+    )
+  })
+
+  it('keeps PowerShell and POSIX recovery guidance literal', () => {
+    expect(
+      renderCommand(['orca', 'literal "quoted" $HOME'], 'win32', {
+        ComSpec: 'powershell.exe'
+      })
+    ).toBe("& 'orca' 'literal \\\"quoted\\\" $HOME'")
+    expect(renderCommand(['orca', 'literal $(do-not-run)'], 'darwin')).toBe(
+      "orca 'literal $(do-not-run)'"
+    )
+  })
 })
diff --git a/src/cli/orchestration-mutation-recovery.ts b/src/cli/orchestration-mutation-recovery.ts
index e3fae18aa8c..9362d5bb2de 100644
--- a/src/cli/orchestration-mutation-recovery.ts
+++ b/src/cli/orchestration-mutation-recovery.ts
@@ -1,5 +1,9 @@
 import { RuntimeClientError } from './runtime-client'
 import { resolveOrchestrationCliExecutable } from './runtime/orchestration-recovery-command'
+import { quoteWindowsCmdArgument } from '../shared/child-process/windows-command-line'
+import { quotePowerShellNativeArgument } from '../shared/powershell-native-argument'
+import { resolveWindowsShellStartupFamily } from '../shared/windows-terminal-shell'
+import type { AgentStartupShell } from '../shared/tui-agent-startup-shell'
 
 export function orchestrationMutationRecoveryError(error: unknown): unknown {
   if (!(error instanceof RuntimeClientError) || !isUnknownMutationOutcomeCode(error.code)) {
@@ -129,8 +133,38 @@ function parseCommandLine(value: string): string[] | undefined {
   return parts.length > 0 ? parts : undefined
 }
 
-function renderCommand(command: readonly string[]): string {
-  return command.map(shellQuote).join(' ')
+export function renderCommand(
+  command: readonly string[],
+  platform: NodeJS.Platform = process.platform,
+  env: NodeJS.ProcessEnv = process.env
+): string {
+  const shell = resolveRecoveryShell(platform, env)
+  const rendered = command.map((value) => quoteRecoveryArgument(value, shell)).join(' ')
+  return shell === 'powershell' && rendered ? `& ${rendered}` : rendered
+}
+
+function resolveRecoveryShell(
+  platform: NodeJS.Platform,
+  env: NodeJS.ProcessEnv
+): AgentStartupShell {
+  if (platform !== 'win32') {
+    return 'posix'
+  }
+  return resolveWindowsShellStartupFamily(
+    env.ORCA_TERMINAL_WINDOWS_SHELL ?? env.ORCA_WINDOWS_SHELL ?? env.ComSpec ?? env.COMSPEC
+  )
+}
+
+function quoteRecoveryArgument(value: string, shell: AgentStartupShell): string {
+  if (shell === 'cmd') {
+    // cmd has no single-quote syntax and expands %VAR% inside double quotes;
+    // use the argv encoder that keeps quote parity and escapes percent pairs.
+    return quoteWindowsCmdArgument(value)
+  }
+  if (shell === 'powershell') {
+    return quotePowerShellNativeArgument(value)
+  }
+  return shellQuote(value)
 }
 
 function shellQuote(value: string): string {
diff --git a/src/main/runtime/runtime-rpc-long-poll-transport.test.ts b/src/main/runtime/runtime-rpc-long-poll-transport.test.ts
index 2286827ddeb..0b32415c9e8 100644
--- a/src/main/runtime/runtime-rpc-long-poll-transport.test.ts
+++ b/src/main/runtime/runtime-rpc-long-poll-transport.test.ts
@@ -32,6 +32,17 @@ vi.mock('../git/worktree', () => {
 })
 
 describe('OrcaRuntimeRpcServer', () => {
+  it('classifies worker-start as a keepalive-backed long poll', () => {
+    expect(
+      longPollClassOf({
+        id: 'req_worker_start',
+        authToken: 'token',
+        method: 'orchestration.workerStart',
+        params: { task: 'task_1', timeoutMs: 60_000 }
+      })
+    ).toBe('wait')
+  })
+
   it('keeps agent-prompt submission sockets alive during verification', () => {
     expect(
       longPollClassOf({
@@ -92,6 +103,45 @@ describe('OrcaRuntimeRpcServer', () => {
   // Exercise the real socket (not a mock) so we catch buffer/flush regressions
   // that a unit-level test would miss.
   describe('long-poll transport (§3.1)', () => {
+    it('emits keepalives while orchestration.workerStart blocks', async () => {
+      const userDataPath = mkdtempSync(join(tmpdir(), 'orca-runtime-rpc-'))
+      const runtime = new OrcaRuntimeService()
+      const server = new OrcaRuntimeRpcServer({
+        runtime,
+        userDataPath,
+        keepaliveIntervalMs: 30
+      })
+      const dispatch = server['dispatcher']
+      vi.spyOn(dispatch, 'dispatch').mockImplementation(async (request) => {
+        await sleep(120)
+        return {
+          id: request.id,
+          ok: true,
+          result: { dispatch: { id: 'dispatch_1' } },
+          _meta: { runtimeId: runtime.getRuntimeId() }
+        }
+      })
+      await server.start()
+
+      try {
+        const metadata = readRuntimeMetadata(userDataPath)
+        const session = openFramedSession(metadata!.transports[0]!.endpoint, {
+          id: 'req_worker_start',
+          authToken: metadata!.authToken,
+          method: 'orchestration.workerStart',
+          params: { task: 'task_1', timeoutMs: 60_000 }
+        })
+        await session.done
+
+        expect(
+          session.frames.filter((frame) => frame._keepalive === true).length
+        ).toBeGreaterThanOrEqual(2)
+        expect(session.frames.filter((frame) => frame.ok !== undefined)).toHaveLength(1)
+      } finally {
+        await server.stop()
+      }
+    })
+
     it('emits keepalive frames while a check --wait handler blocks', async () => {
       const userDataPath = mkdtempSync(join(tmpdir(), 'orca-runtime-rpc-'))
       const runtime = new OrcaRuntimeService()
diff --git a/src/main/runtime/runtime-rpc.ts b/src/main/runtime/runtime-rpc.ts
index 6d897d19641..4ac6c3287c0 100644
--- a/src/main/runtime/runtime-rpc.ts
+++ b/src/main/runtime/runtime-rpc.ts
@@ -446,6 +446,12 @@ type LongPollClass = 'ask' | 'wait'
 
 // Why: single classifier for long-poll requests (handlers that block on an external event), shared by counter/abort/keepalive. See §3.1.
 export function longPollClassOf(request: RpcRequest): LongPollClass | null {
+  // Worker start waits for readiness and then verifies the submitted prompt;
+  // the complete operation can run for 90–110s. Keep every local transport
+  // (Unix sockets and Windows named pipes) alive for that long poll.
+  if (request.method === 'orchestration.workerStart') {
+    return 'wait'
+  }
   if (request.method === 'terminal.wait') {
     return 'wait'
   }