diff --git a/src/main/ai-vault/isolated-scan-roots.ts b/src/main/ai-vault/isolated-scan-roots.ts
new file mode 100644
index 00000000000..0fe3057f0a5
--- /dev/null
+++ b/src/main/ai-vault/isolated-scan-roots.ts
@@ -0,0 +1,32 @@
+import { join } from 'path'
+
+// Per-test scan roots that point every agent source at a throwaway temp dir, so
+// the scanner never reads the developer's real ~/.claude, ~/.codex, or the
+// shared OpenCode SQLite database while tests run.
+export function isolatedScanRoots(root: string) {
+  return {
+    claudeProjectsDir: join(root, 'claude-projects'),
+    codexSessionsDir: join(root, 'codex-sessions'),
+    geminiSessionsDir: join(root, 'gemini-sessions'),
+    copilotSessionsDir: join(root, 'copilot-sessions'),
+    cursorProjectsDir: join(root, 'cursor-projects'),
+    opencodeStorageDir: join(root, 'opencode-storage'),
+    // Why: prevent the SQLite scanner from picking up the real
+    // ~/.local/share/opencode/opencode.db during tests.
+    opencodeDbPaths: [] as readonly string[],
+    grokSessionsDir: join(root, 'grok-sessions'),
+    devinTranscriptsDir: join(root, 'devin-transcripts'),
+    hermesSessionsDir: join(root, 'hermes-sessions'),
+    rovoSessionsDir: join(root, 'rovo-sessions'),
+    openclawStateDir: join(root, 'openclaw-state'),
+    openclawLegacyStateDir: join(root, 'openclaw-legacy-state'),
+    piSessionsDir: join(root, 'pi-sessions'),
+    droidSessionsDir: join(root, 'droid-sessions'),
+    droidProjectsDir: join(root, 'droid-projects'),
+    kimiSessionsDir: join(root, 'kimi-sessions')
+  }
+}
+
+export function jsonLines(records: unknown[]): string {
+  return records.map((record) => JSON.stringify(record)).join('\n')
+}
diff --git a/src/main/ai-vault/session-scanner-claude-path-only.test.ts b/src/main/ai-vault/session-scanner-claude-path-only.test.ts
new file mode 100644
index 00000000000..4953af36700
--- /dev/null
+++ b/src/main/ai-vault/session-scanner-claude-path-only.test.ts
@@ -0,0 +1,60 @@
+import { mkdtemp, mkdir, rm, writeFile } from 'fs/promises'
+import { tmpdir } from 'os'
+import { join } from 'path'
+import { afterEach, describe, expect, it } from 'vitest'
+import { isolatedScanRoots, jsonLines } from './isolated-scan-roots'
+import { scanAiVaultSessions } from './session-scanner'
+
+let tempRoots: string[] = []
+
+afterEach(async () => {
+  await Promise.all(tempRoots.map((root) => rm(root, { recursive: true, force: true })))
+  tempRoots = []
+})
+
+describe('scanAiVaultSessions path-only Claude transcripts', () => {
+  it('keeps cwd null because the scanner does not decode the project folder', async () => {
+    // The scanner intentionally does NOT decode the Claude project folder name
+    // back into a cwd (decoding is lossy for names with punctuation). It keeps
+    // cwd null; the renderer's workspace filter and resume builder match the file
+    // path against known worktree paths instead (see ai-vault-session-filters and
+    // ai-vault-resume-command tests, which prove the user-visible bug is fixed).
+    const root = await mkdtemp(join(tmpdir(), 'orca-ai-vault-claude-project-path-'))
+    tempRoots.push(root)
+    const roots = isolatedScanRoots(root)
+    const claudeProjectDir = join(
+      roots.claudeProjectsDir,
+      '-Users-ada-orca-workspaces-orca-path-only-session'
+    )
+    await mkdir(claudeProjectDir, { recursive: true })
+
+    const filePath = join(claudeProjectDir, '77777777-1111-4222-8333-444444444444.jsonl')
+    await writeFile(
+      filePath,
+      jsonLines([
+        {
+          type: 'user',
+          sessionId: '77777777-1111-4222-8333-444444444444',
+          timestamp: '2026-06-12T10:00:00.000Z',
+          isMeta: false,
+          message: { role: 'user', content: 'Find the path-only Claude session' }
+        }
+      ])
+    )
+
+    const result = await scanAiVaultSessions({
+      ...roots,
+      platform: 'darwin'
+    })
+
+    expect(result.issues).toEqual([])
+    expect(result.sessions).toHaveLength(1)
+    expect(result.sessions[0]).toMatchObject({
+      agent: 'claude',
+      sessionId: '77777777-1111-4222-8333-444444444444',
+      cwd: null,
+      filePath,
+      resumeCommand: "claude --resume '77777777-1111-4222-8333-444444444444'"
+    })
+  })
+})
diff --git a/src/main/ai-vault/session-scanner.test.ts b/src/main/ai-vault/session-scanner.test.ts
index a4c5cf6540f..2e56d4bd188 100644
--- a/src/main/ai-vault/session-scanner.test.ts
+++ b/src/main/ai-vault/session-scanner.test.ts
@@ -3,6 +3,7 @@ import { tmpdir } from 'os'
 import { join } from 'path'
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import { AI_VAULT_AGENTS, buildAiVaultResumeCommand } from '../../shared/ai-vault-types'
+import { isolatedScanRoots, jsonLines } from './isolated-scan-roots'
 import { scanAiVaultSessions } from './session-scanner'
 
 let tempRoots: string[] = []
@@ -13,34 +14,6 @@ afterEach(async () => {
   tempRoots = []
 })
 
-function isolatedScanRoots(root: string) {
-  return {
-    claudeProjectsDir: join(root, 'claude-projects'),
-    codexSessionsDir: join(root, 'codex-sessions'),
-    geminiSessionsDir: join(root, 'gemini-sessions'),
-    copilotSessionsDir: join(root, 'copilot-sessions'),
-    cursorProjectsDir: join(root, 'cursor-projects'),
-    opencodeStorageDir: join(root, 'opencode-storage'),
-    // Why: prevent the SQLite scanner from picking up the real
-    // ~/.local/share/opencode/opencode.db during tests.
-    opencodeDbPaths: [] as readonly string[],
-    grokSessionsDir: join(root, 'grok-sessions'),
-    devinTranscriptsDir: join(root, 'devin-transcripts'),
-    hermesSessionsDir: join(root, 'hermes-sessions'),
-    rovoSessionsDir: join(root, 'rovo-sessions'),
-    openclawStateDir: join(root, 'openclaw-state'),
-    openclawLegacyStateDir: join(root, 'openclaw-legacy-state'),
-    piSessionsDir: join(root, 'pi-sessions'),
-    droidSessionsDir: join(root, 'droid-sessions'),
-    droidProjectsDir: join(root, 'droid-projects'),
-    kimiSessionsDir: join(root, 'kimi-sessions')
-  }
-}
-
-function jsonLines(records: unknown[]): string {
-  return records.map((record) => JSON.stringify(record)).join('\n')
-}
-
 describe('scanAiVaultSessions', () => {
   it('indexes Claude and Codex transcripts with resume commands', async () => {
     const root = await mkdtemp(join(tmpdir(), 'orca-ai-vault-'))
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-session-filters.test.ts b/src/renderer/src/components/right-sidebar/ai-vault-session-filters.test.ts
index 5acfd125b09..8209c2054c5 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-session-filters.test.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-session-filters.test.ts
@@ -86,6 +86,70 @@ describe('filterAiVaultSessions', () => {
     ).toEqual(['claude:old-path'])
   })
 
+  it('includes a path-only Claude session whose file matches the active worktree path', () => {
+    const pathOnlySession: AiVaultSession = {
+      ...baseSession,
+      id: 'claude:path-only',
+      cwd: null,
+      filePath:
+        '/Users/ada/.claude/projects/-Users-ada-orca-workspaces-orca-path-only-session/sess.jsonl'
+    }
+
+    expect(
+      filterAiVaultSessions([pathOnlySession], {
+        query: '',
+        agents: ['claude'],
+        scope: 'workspace',
+        sort: 'updated',
+        activeWorktreePaths: ['/Users/ada/orca/workspaces/orca/path-only-session'],
+        hideEmptySessions: true
+      }).map((session) => session.id)
+    ).toEqual(['claude:path-only'])
+  })
+
+  it('excludes a path-only Claude session for a non-matching worktree path', () => {
+    const pathOnlySession: AiVaultSession = {
+      ...baseSession,
+      id: 'claude:path-only',
+      cwd: null,
+      filePath:
+        '/Users/ada/.claude/projects/-Users-ada-orca-workspaces-orca-path-only-session/sess.jsonl'
+    }
+
+    expect(
+      filterAiVaultSessions([pathOnlySession], {
+        query: '',
+        agents: ['claude'],
+        scope: 'workspace',
+        sort: 'updated',
+        activeWorktreePaths: ['/Users/ada/orca/workspaces/orca/other-session'],
+        hideEmptySessions: true
+      })
+    ).toEqual([])
+  })
+
+  it('does not apply the path-only fallback to non-Claude null-cwd sessions', () => {
+    const codexPathOnly: AiVaultSession = {
+      ...baseSession,
+      id: 'codex:path-only',
+      agent: 'codex',
+      cwd: null,
+      filePath:
+        '/Users/ada/.claude/projects/-Users-ada-orca-workspaces-orca-path-only-session/sess.jsonl'
+    }
+
+    expect(
+      filterAiVaultSessions([codexPathOnly], {
+        query: '',
+        agents: ['codex'],
+        scope: 'workspace',
+        sort: 'updated',
+        activeWorktreePaths: ['/Users/ada/orca/workspaces/orca/path-only-session'],
+        hideEmptySessions: true
+      })
+    ).toEqual([])
+  })
+
   it('returns no workspace matches when active workspace paths are empty', () => {
     expect(
       filterAiVaultSessions([baseSession], {
diff --git a/src/renderer/src/components/right-sidebar/ai-vault-session-filters.ts b/src/renderer/src/components/right-sidebar/ai-vault-session-filters.ts
index f0422547761..20d25bbcfac 100644
--- a/src/renderer/src/components/right-sidebar/ai-vault-session-filters.ts
+++ b/src/renderer/src/components/right-sidebar/ai-vault-session-filters.ts
@@ -5,6 +5,7 @@ import {
   normalizeRuntimePathSeparators
 } from '../../../../shared/cross-platform-path'
 import { isClipboardTextByteLengthOverLimit } from '../../../../shared/clipboard-text'
+import { isClaudeSessionFileForWorkspace } from '../../../../shared/claude-project-path'
 import { parseWslUncPath } from '../../../../shared/wsl-paths'
 import type {
   AiVaultAgent,
@@ -71,16 +72,8 @@ export function filterAiVaultSessions(
       if (filters.hideEmptySessions && session.messageCount === 0) {
         return false
       }
-      if (filters.scope === 'workspace') {
-        const cwd = session.cwd
-        if (
-          !cwd ||
-          !filters.activeWorktreePaths.some((pathValue) =>
-            isAiVaultSessionInWorkspacePath(pathValue, cwd)
-          )
-        ) {
-          return false
-        }
+      if (filters.scope === 'workspace' && !isSessionInWorkspaceScope(session, filters)) {
+        return false
       }
       if (filters.scope === 'project') {
         if (!filters.activeProjectKey) {
@@ -278,6 +271,26 @@ function addAiVaultWorkspaceScopePath(paths: string[], pathValue: string): void
   paths.push(trimmedPath)
 }
 
+function isSessionInWorkspaceScope(
+  session: AiVaultSession,
+  filters: Pick<AiVaultSessionFilterState, 'activeWorktreePaths'>
+): boolean {
+  const cwd = session.cwd
+  if (cwd) {
+    return filters.activeWorktreePaths.some((pathValue) =>
+      isAiVaultSessionInWorkspacePath(pathValue, cwd)
+    )
+  }
+  // Path-only Claude transcripts encode their cwd only in the project folder
+  // name; match the file path against known worktree paths instead.
+  return (
+    session.agent === 'claude' &&
+    filters.activeWorktreePaths.some((pathValue) =>
+      isClaudeSessionFileForWorkspace(session.filePath, pathValue)
+    )
+  )
+}
+
 function isAiVaultSessionInWorkspacePath(workspacePath: string, sessionCwd: string): boolean {
   if (isPathInsideOrEqual(workspacePath, sessionCwd)) {
     return true
diff --git a/src/renderer/src/lib/ai-vault-resume-command.test.ts b/src/renderer/src/lib/ai-vault-resume-command.test.ts
index 1d44f82a78f..b32fb679e25 100644
--- a/src/renderer/src/lib/ai-vault-resume-command.test.ts
+++ b/src/renderer/src/lib/ai-vault-resume-command.test.ts
@@ -59,12 +59,79 @@ describe('ai vault resume command runtime', () => {
           agent: 'claude',
           sessionId: 'session one',
           cwd: 'C:\\Users\\alice\\repo',
-          codexHome: null
+          codexHome: null,
+          filePath: 'C:\\Users\\alice\\.claude\\projects\\repo\\s.jsonl'
         }
       })
     ).toBe('cmd /d /s /c "cd /d ""C:\\Users\\alice\\repo"" && claude --resume ""session one"""')
   })
 
+  it('resumes a path-only Claude session into the matching worktree cwd', () => {
+    const state = makeState({
+      worktreePath: '/Users/ada/orca/workspaces/orca/path-only-session',
+      localWindowsRuntimePreference: { kind: 'wsl', distro: 'Ubuntu' }
+    })
+
+    expect(
+      buildAiVaultResumeCommandForWorktree({
+        state,
+        worktreeId: 'repo-1::worktree-1',
+        session: {
+          agent: 'claude',
+          sessionId: 'session one',
+          cwd: null,
+          codexHome: null,
+          filePath:
+            '/Users/ada/.claude/projects/-Users-ada-orca-workspaces-orca-path-only-session/s.jsonl'
+        }
+      })
+    ).toBe(
+      "cd '/Users/ada/orca/workspaces/orca/path-only-session' && claude --resume 'session one'"
+    )
+  })
+
+  it('keeps a no-cwd command when a path-only Claude session does not match the worktree', () => {
+    const state = makeState({
+      worktreePath: '/Users/ada/orca/workspaces/orca/other-session',
+      localWindowsRuntimePreference: { kind: 'wsl', distro: 'Ubuntu' }
+    })
+
+    expect(
+      buildAiVaultResumeCommandForWorktree({
+        state,
+        worktreeId: 'repo-1::worktree-1',
+        session: {
+          agent: 'claude',
+          sessionId: 'session one',
+          cwd: null,
+          codexHome: null,
+          filePath:
+            '/Users/ada/.claude/projects/-Users-ada-orca-workspaces-orca-path-only-session/s.jsonl'
+        }
+      })
+    ).toBe("claude --resume 'session one'")
+  })
+
+  it('resumes a WSL path-only Claude session into the linux cwd', () => {
+    const state = makeState({
+      worktreePath: '\\\\wsl.localhost\\Ubuntu\\home\\ada\\repo'
+    })
+
+    expect(
+      buildAiVaultResumeCommandForWorktree({
+        state,
+        worktreeId: 'repo-1::worktree-1',
+        session: {
+          agent: 'claude',
+          sessionId: 'session one',
+          cwd: null,
+          codexHome: null,
+          filePath: '/Users/ada/.claude/projects/-home-ada-repo/s.jsonl'
+        }
+      })
+    ).toBe("cd '/home/ada/repo' && claude --resume 'session one'")
+  })
+
   it('uses POSIX command wrapping for Windows-path projects forced to WSL', () => {
     const state = makeState({
       worktreePath: 'C:\\Users\\alice\\repo',
@@ -80,7 +147,8 @@ describe('ai vault resume command runtime', () => {
           agent: 'claude',
           sessionId: 'session one',
           cwd: '/home/alice/repo',
-          codexHome: null
+          codexHome: null,
+          filePath: '/home/alice/.claude/projects/repo/s.jsonl'
         }
       })
     ).toBe("cd '/home/alice/repo' && claude --resume 'session one'")
@@ -107,7 +175,8 @@ describe('ai vault resume command runtime', () => {
           agent: 'codex',
           sessionId: 'session one',
           cwd: '/home/alice/repo',
-          codexHome: '\\\\wsl.localhost\\Ubuntu\\home\\alice\\.codex'
+          codexHome: '\\\\wsl.localhost\\Ubuntu\\home\\alice\\.codex',
+          filePath: '/home/alice/.codex/sessions/s.jsonl'
         }
       })
     ).toBe("cd '/home/alice/repo' && CODEX_HOME='/home/alice/.codex' codex resume 'session one'")
diff --git a/src/renderer/src/lib/ai-vault-resume-command.ts b/src/renderer/src/lib/ai-vault-resume-command.ts
index eb628023552..804f0011305 100644
--- a/src/renderer/src/lib/ai-vault-resume-command.ts
+++ b/src/renderer/src/lib/ai-vault-resume-command.ts
@@ -1,32 +1,76 @@
 import { buildAiVaultResumeCommand, type AiVaultSession } from '../../../shared/ai-vault-types'
+import { resolveClaudeSessionWorkspaceCwd } from '../../../shared/claude-project-path'
 import { parseWslUncPath } from '../../../shared/wsl-paths'
 import type { AppState } from '@/store/types'
 import { getLocalProjectExecutionRuntimeContext } from '@/lib/local-preflight-context'
 import { CLIENT_PLATFORM } from '@/lib/new-workspace'
 
-type AiVaultResumeCommandSession = Pick<AiVaultSession, 'agent' | 'sessionId' | 'cwd' | 'codexHome'>
+type AiVaultResumeWorktree = { id: string; path?: string }
+
+type AiVaultResumeState = Pick<
+  AppState,
+  'activeRepoId' | 'activeWorktreeId' | 'projects' | 'repos' | 'settings' | 'worktreesByRepo'
+>
+
+type AiVaultResumeCommandSession = Pick<
+  AiVaultSession,
+  'agent' | 'sessionId' | 'cwd' | 'codexHome' | 'filePath'
+>
 
 export function buildAiVaultResumeCommandForWorktree(args: {
-  state: Pick<
-    AppState,
-    'activeRepoId' | 'activeWorktreeId' | 'projects' | 'repos' | 'settings' | 'worktreesByRepo'
-  >
+  state: AiVaultResumeState
   worktreeId?: string | null
   session: AiVaultResumeCommandSession
   commandOverride?: string | null
 }): string {
   const platform = getAiVaultResumePlatform(args.state, args.worktreeId)
   const codexHome = getAiVaultResumeCodexHome(args.session.codexHome, platform)
+  const cwd = resolveAiVaultResumeCwd(args.state, args.worktreeId, args.session)
   return buildAiVaultResumeCommand({
     agent: args.session.agent,
     sessionId: args.session.sessionId,
-    cwd: args.session.cwd,
+    cwd,
     platform,
     commandOverride: args.commandOverride,
     codexHome
   })
 }
 
+function resolveAiVaultResumeCwd(
+  state: AiVaultResumeState,
+  worktreeId: string | null | undefined,
+  session: AiVaultResumeCommandSession
+): string | null {
+  if (session.cwd) {
+    return session.cwd
+  }
+  // Path-only Claude transcripts carry no cwd; resume into the target worktree
+  // only when its path encodes to the transcript's Claude project folder.
+  if (session.agent !== 'claude') {
+    return null
+  }
+  const worktreePath = findAiVaultResumeWorktree(state, worktreeId)?.path
+  if (!worktreePath) {
+    return null
+  }
+  return resolveClaudeSessionWorkspaceCwd(session.filePath, worktreePath)
+}
+
+function findAiVaultResumeWorktree(
+  state: AiVaultResumeState,
+  worktreeId: string | null | undefined
+): AiVaultResumeWorktree | null {
+  const targetWorktreeId = worktreeId ?? state.activeWorktreeId
+  if (!targetWorktreeId) {
+    return null
+  }
+  return (
+    Object.values(state.worktreesByRepo ?? {})
+      .flat()
+      .find((candidate) => candidate.id === targetWorktreeId) ?? null
+  )
+}
+
 function getAiVaultResumeCodexHome(
   codexHome: string | null,
   platform: NodeJS.Platform
@@ -40,10 +84,7 @@ function getAiVaultResumeCodexHome(
 }
 
 export function getAiVaultResumePlatform(
-  state: Pick<
-    AppState,
-    'activeRepoId' | 'activeWorktreeId' | 'projects' | 'repos' | 'settings' | 'worktreesByRepo'
-  >,
+  state: AiVaultResumeState,
   worktreeId?: string | null
 ): NodeJS.Platform {
   const projectRuntime = getLocalProjectExecutionRuntimeContext(state, worktreeId, CLIENT_PLATFORM)
@@ -54,11 +95,6 @@ export function getAiVaultResumePlatform(
     return 'linux'
   }
 
-  const targetWorktreeId = worktreeId ?? state.activeWorktreeId
-  const worktree = targetWorktreeId
-    ? Object.values(state.worktreesByRepo ?? {})
-        .flat()
-        .find((candidate) => candidate.id === targetWorktreeId)
-    : null
+  const worktree = findAiVaultResumeWorktree(state, worktreeId)
   return worktree?.path && parseWslUncPath(worktree.path) ? 'linux' : CLIENT_PLATFORM
 }
diff --git a/src/shared/claude-project-path.test.ts b/src/shared/claude-project-path.test.ts
new file mode 100644
index 00000000000..d0bc01887ce
--- /dev/null
+++ b/src/shared/claude-project-path.test.ts
@@ -0,0 +1,99 @@
+import { describe, expect, it } from 'vitest'
+import {
+  encodeClaudeProjectPath,
+  isClaudeSessionFileForWorkspace,
+  resolveClaudeSessionWorkspaceCwd
+} from './claude-project-path'
+
+describe('encodeClaudeProjectPath', () => {
+  it('replaces every non-alphanumeric char with a dash without collapsing runs', () => {
+    expect(encodeClaudeProjectPath('/Users/ada/orca/workspaces/orca/path-only-session')).toBe(
+      '-Users-ada-orca-workspaces-orca-path-only-session'
+    )
+    // `/.` produces `--`, not a single dash (no run collapsing).
+    expect(encodeClaudeProjectPath('/Users/ada/.superset/worktrees/foo')).toBe(
+      '-Users-ada--superset-worktrees-foo'
+    )
+    expect(encodeClaudeProjectPath('/Users/ada/source/orca/.claude/worktrees/foo')).toBe(
+      '-Users-ada-source-orca--claude-worktrees-foo'
+    )
+  })
+
+  it('preserves POSIX case but lowercases Windows-flavored paths', () => {
+    expect(encodeClaudeProjectPath('/Users/Ada/Repo')).toBe('-Users-Ada-Repo')
+    expect(encodeClaudeProjectPath('C:\\Users\\Ada\\repo')).toBe('c--users-ada-repo')
+  })
+
+  it('trims a trailing separator before encoding', () => {
+    expect(encodeClaudeProjectPath('/Users/ada/repo/')).toBe('-Users-ada-repo')
+  })
+})
+
+describe('resolveClaudeSessionWorkspaceCwd', () => {
+  const fileFor = (folder: string): string =>
+    `/Users/ada/.claude/projects/${folder}/77777777-1111-4222-8333-444444444444.jsonl`
+
+  it('matches an all-slash workspace path to its Claude folder', () => {
+    const workspace = '/Users/ada/orca/workspaces/orca/path-only-session'
+    expect(
+      resolveClaudeSessionWorkspaceCwd(
+        fileFor('-Users-ada-orca-workspaces-orca-path-only-session'),
+        workspace
+      )
+    ).toBe(workspace)
+  })
+
+  it('matches a dotted/underscored worktree path a slash-only encoder would miss', () => {
+    const workspace = '/Users/ada/source/orca/.claude/worktrees/my_project'
+    expect(
+      resolveClaudeSessionWorkspaceCwd(
+        fileFor('-Users-ada-source-orca--claude-worktrees-my-project'),
+        workspace
+      )
+    ).toBe(workspace)
+  })
+
+  it('does not match when a single encoded character differs', () => {
+    expect(
+      resolveClaudeSessionWorkspaceCwd(
+        fileFor('-Users-ada-orca-workspaces-orca-path-only-sessions'),
+        '/Users/ada/orca/workspaces/orca/path-only-session'
+      )
+    ).toBeNull()
+  })
+
+  it('documents punctuation-variant paths collide under Claude project encoding', () => {
+    const folder = fileFor('-Users-ada-orca-workspaces-foo-bar')
+
+    expect(resolveClaudeSessionWorkspaceCwd(folder, '/Users/ada/orca/workspaces/foo-bar')).toBe(
+      '/Users/ada/orca/workspaces/foo-bar'
+    )
+    expect(resolveClaudeSessionWorkspaceCwd(folder, '/Users/ada/orca/workspaces/foo_bar')).toBe(
+      '/Users/ada/orca/workspaces/foo_bar'
+    )
+  })
+
+  it('matches a WSL UNC worktree against its linux-encoded folder and returns the linux cwd', () => {
+    expect(
+      resolveClaudeSessionWorkspaceCwd(
+        fileFor('-home-ada-repo'),
+        '\\\\wsl.localhost\\Ubuntu\\home\\ada\\repo'
+      )
+    ).toBe('/home/ada/repo')
+  })
+
+  it('tolerates Windows case drift between recorded cwd and stored worktree path', () => {
+    expect(
+      resolveClaudeSessionWorkspaceCwd(fileFor('c--users-ada-repo'), 'C:\\Users\\Ada\\repo')
+    ).toBe('C:\\Users\\Ada\\repo')
+  })
+
+  it('exposes a boolean predicate', () => {
+    expect(isClaudeSessionFileForWorkspace(fileFor('-Users-ada-repo'), '/Users/ada/repo')).toBe(
+      true
+    )
+    expect(isClaudeSessionFileForWorkspace(fileFor('-Users-ada-repo'), '/Users/ada/other')).toBe(
+      false
+    )
+  })
+})
diff --git a/src/shared/claude-project-path.ts b/src/shared/claude-project-path.ts
new file mode 100644
index 00000000000..a7996917838
--- /dev/null
+++ b/src/shared/claude-project-path.ts
@@ -0,0 +1,60 @@
+import {
+  isWindowsAbsolutePathLike,
+  normalizeRuntimePathForComparison,
+  normalizeRuntimePathSeparators
+} from './cross-platform-path'
+import { parseWslUncPath } from './wsl-paths'
+
+// Claude Code names each project directory after the session's absolute cwd by
+// replacing EVERY non-alphanumeric character with '-' — it does not collapse
+// runs of '-' and preserves case (verified against real on-disk names, e.g.
+// `/Users/ada/.claude/worktrees/foo` -> `-Users-ada--claude-worktrees-foo`).
+// We never decode these names (lossy and non-injective); instead we encode a
+// KNOWN workspace path and compare, which keeps the fallback scoped to the
+// worktree the user is currently viewing/resuming from.
+export function encodeClaudeProjectPath(workspacePath: string): string {
+  return normalizeRuntimePathForComparison(workspacePath).replace(/[^a-zA-Z0-9]/g, '-')
+}
+
+// Returns the effective cwd to use for a path-only Claude transcript when its
+// project folder encodes exactly to one of the given workspace candidates, or
+// null when none match. For WSL UNC worktrees the returned cwd is the Linux
+// path so POSIX resume commands cd into a real directory, not a UNC path.
+export function resolveClaudeSessionWorkspaceCwd(
+  filePath: string,
+  workspacePath: string
+): string | null {
+  const folder = claudeProjectFolderName(filePath)
+  if (!folder) {
+    return null
+  }
+
+  for (const candidate of claudeWorkspaceMatchCandidates(workspacePath)) {
+    // Claude preserves the original cwd casing in the folder name, so lowercase
+    // it only on the Windows branch to mirror normalizeRuntimePathForComparison.
+    const folderKey = isWindowsAbsolutePathLike(candidate) ? folder.toLowerCase() : folder
+    if (encodeClaudeProjectPath(candidate) === folderKey) {
+      return candidate
+    }
+  }
+  return null
+}
+
+export function isClaudeSessionFileForWorkspace(filePath: string, workspacePath: string): boolean {
+  return resolveClaudeSessionWorkspaceCwd(filePath, workspacePath) !== null
+}
+
+function claudeProjectFolderName(filePath: string): string {
+  // The transcript's immediate parent directory is Claude's encoded project
+  // folder name. String-only (no fs): normalize separators then take the
+  // second-to-last segment.
+  const segments = normalizeRuntimePathSeparators(filePath).split('/').filter(Boolean)
+  return segments.at(-2) ?? ''
+}
+
+function claudeWorkspaceMatchCandidates(workspacePath: string): string[] {
+  // Claude under WSL encodes the Linux cwd, but Orca may store the worktree as a
+  // Windows UNC path; try the Linux path too so the encoded folder can match.
+  const wsl = parseWslUncPath(workspacePath)
+  return wsl ? [workspacePath, wsl.linuxPath] : [workspacePath]
+}