fix(native-chat): constrain live transcript retries

src/main/native-chat/host-readable-transcript-path.test.ts

@@ -2,6 +2,7 @@ import { beforeEach, describe, expect, it, vi } from 'vitest'
 
 import {
   isGuestAbsoluteLinuxPath,
+  isTranscriptPathCompatibleWithHost,
   needsWslHostTranslation,
   resetHostReadableTranscriptPathCacheForTests,
   toHostReadableTranscriptPath,
@@ -44,6 +45,28 @@ describe('needsWslHostTranslation', () => {
   })
 })
 
+describe('isTranscriptPathCompatibleWithHost', () => {
+  it('constrains exact Windows paths to their authoritative host', () => {
+    expect(
+      isTranscriptPathCompatibleWithHost(ROLLOUT_UNC, { kind: 'wsl', distro: 'Ubuntu' }, 'win32')
+    ).toBe(true)
+    expect(
+      isTranscriptPathCompatibleWithHost(ROLLOUT_UNC, { kind: 'wsl', distro: 'Debian' }, 'win32')
+    ).toBe(false)
+    expect(isTranscriptPathCompatibleWithHost(ROLLOUT_UNC, { kind: 'host' }, 'win32')).toBe(false)
+    expect(
+      isTranscriptPathCompatibleWithHost('C:\\Users\\ada\\x.jsonl', { kind: 'host' }, 'win32')
+    ).toBe(true)
+    expect(
+      isTranscriptPathCompatibleWithHost(
+        'C:\\Users\\ada\\x.jsonl',
+        { kind: 'wsl', distro: 'Ubuntu' },
+        'win32'
+      )
+    ).toBe(false)
+  })
+})
+
 describe('toHostReadableTranscriptPath', () => {
   it('translates a WSL guest path to its UNC twin on Windows (#10326)', async () => {
     await expect(

src/main/native-chat/host-readable-transcript-path.ts

@@ -31,6 +31,27 @@ export function needsWslHostTranslation(
   return platform === 'win32' && isGuestAbsoluteLinuxPath(path.trim())
 }
 
+export function isTranscriptPathCompatibleWithHost(
+  path: string,
+  transcriptHost: NativeChatTranscriptHost,
+  platform: NodeJS.Platform = process.platform
+): boolean {
+  if (platform !== 'win32') {
+    return true
+  }
+  const unc = parseWslUncPath(path)
+  if (transcriptHost.kind === 'host') {
+    return !unc && !needsWslHostTranslation(path, platform)
+  }
+  const distro = transcriptHost.distro.trim()
+  return (
+    distro.length > 0 &&
+    (unc
+      ? unc.distro.toLowerCase() === distro.toLowerCase()
+      : needsWslHostTranslation(path, platform))
+  )
+}
+
 export type HostReadableTranscriptPathDeps = {
   platform?: NodeJS.Platform
   pathExists?: (path: string) => Promise<boolean>
@@ -135,19 +156,13 @@ export async function toHostReadableTranscriptPath(
     deps.pathExists ?? ((candidate: string) => pathExistsAsync(candidate, deps.signal))
   const platform = deps.platform ?? process.platform
   if (platform === 'win32' && deps.transcriptHost) {
+    if (!isTranscriptPathCompatibleWithHost(path, deps.transcriptHost, platform)) {
+      return null
+    }
     const unc = parseWslUncPath(path)
     if (unc) {
-      if (
-        deps.transcriptHost.kind === 'host' ||
-        unc.distro.toLowerCase() !== deps.transcriptHost.distro.trim().toLowerCase()
-      ) {
-        return null
-      }
       return (await pathExists(path)) ? path : null
     }
-    if (deps.transcriptHost.kind === 'wsl' && !needsWslHostTranslation(path, platform)) {
-      return null
-    }
   }
   // Why: classify BEFORE probing — Win32 resolves a bare `/home/…` against the
   // current drive (`C:\home\…`), so a probe first could bind chat to a local

src/main/native-chat/transcript-watch-resolve-poll.test.ts

@@ -117,6 +117,76 @@ describe('native chat transcript resolve polling', () => {
     subscription.unsubscribe()
   })
 
+  it.each([
+    [
+      'host provenance on WSL UNC',
+      { kind: 'host' as const },
+      '\\\\wsl.localhost\\Ubuntu\\home\\ada\\session.jsonl'
+    ],
+    [
+      'wrong WSL distro provenance',
+      { kind: 'wsl' as const, distro: 'Debian' },
+      '\\\\wsl.localhost\\Ubuntu\\home\\ada\\session.jsonl'
+    ],
+    [
+      'WSL provenance on a host drive',
+      { kind: 'wsl' as const, distro: 'Ubuntu' },
+      'C:\\Users\\ada\\session.jsonl'
+    ],
+    [
+      'host provenance on extended WSL UNC',
+      { kind: 'host' as const },
+      '\\\\?\\UNC\\wsl.localhost\\Ubuntu\\home\\ada\\session.jsonl'
+    ]
+  ])('does not fast-install %s after an initial miss', async (_name, transcriptHost, path) => {
+    setPlatform('win32')
+    const subscription = await subscribeNativeChatTranscript({
+      agent: 'claude',
+      sessionId: 'session-id',
+      transcriptPath: path,
+      transcriptHost,
+      resolvePollIntervalMs: 10,
+      onAppend: () => {}
+    })
+
+    await vi.advanceTimersByTimeAsync(100)
+    expect(mocks.install).not.toHaveBeenCalled()
+    subscription.unsubscribe()
+  })
+
+  it('preserves raw exact-path retries when provenance is unavailable', async () => {
+    setPlatform('win32')
+    const unc = '\\\\wsl.localhost\\Ubuntu\\home\\ada\\session.jsonl'
+    const subscription = await subscribeNativeChatTranscript({
+      agent: 'claude',
+      sessionId: 'session-id',
+      transcriptPath: unc,
+      resolvePollIntervalMs: 10,
+      onAppend: () => {}
+    })
+
+    await vi.advanceTimersByTimeAsync(100)
+    expect(mocks.install).toHaveBeenCalledWith(unc, expect.any(Function), expect.any(Object))
+    subscription.unsubscribe()
+  })
+
+  it('fast-installs an exact path that matches WSL provenance', async () => {
+    setPlatform('win32')
+    const unc = '\\\\wsl.localhost\\Ubuntu\\home\\ada\\session.jsonl'
+    const subscription = await subscribeNativeChatTranscript({
+      agent: 'claude',
+      sessionId: 'session-id',
+      transcriptPath: unc,
+      transcriptHost: { kind: 'wsl', distro: 'Ubuntu' },
+      resolvePollIntervalMs: 10,
+      onAppend: () => {}
+    })
+
+    await vi.advanceTimersByTimeAsync(100)
+    expect(mocks.install).toHaveBeenCalledWith(unc, expect.any(Function), expect.any(Object))
+    subscription.unsubscribe()
+  })
+
   it('keeps resolving on every retry when no exact hook path is available', async () => {
     const subscription = await subscribeNativeChatTranscript({
       agent: 'claude',

src/main/native-chat/transcript-watch.ts

@@ -1,6 +1,7 @@
 import { extname } from 'node:path'
 import type { NativeChatMessage } from '../../shared/native-chat-types'
 import {
+  isTranscriptPathCompatibleWithHost,
   needsWslHostTranslation,
   toHostReadableTranscriptPath
 } from './host-readable-transcript-path'
@@ -111,9 +112,14 @@ function subscribeViaResolvePoll(
     try {
       if (exactPath && !hostReadableExactPath) {
         if (!needsWslHostTranslation(exactPath)) {
-          // Non-WSL paths stay raw: installTranscriptWatcher already handles a
-          // not-yet-created file, so don't spend an extra probe per tick.
-          hostReadableExactPath = exactPath
+          // Why: live retries must enforce the same PTY provenance as reads
+          // before installing a watcher on an exact UNC or drive path.
+          if (
+            !args.transcriptHost ||
+            isTranscriptPathCompatibleWithHost(exactPath, args.transcriptHost)
+          ) {
+            hostReadableExactPath = exactPath
+          }
         } else if (Date.now() - lastWslTranslateAt >= FALLBACK_RESOLVE_POLL_MS) {
           // Why: translating probes the UNC twin per distro over the 9P
           // share, and the guest file usually appears well after the hook does,