diff --git a/cli/src/__tests__/project-files-chat-id.test.ts b/cli/src/__tests__/project-files-chat-id.test.ts
index 73f504f5fa..c9d732ccf6 100644
--- a/cli/src/__tests__/project-files-chat-id.test.ts
+++ b/cli/src/__tests__/project-files-chat-id.test.ts
@@ -8,7 +8,10 @@ import {
   getCurrentChatId,
   setCurrentChatId,
   startNewChat,
+  setProjectRoot,
+  getProjectDataDir,
 } from '../project-files'
+import { getConfigDir } from '../utils/config-dir'
 
 describe('chat id lifecycle', () => {
   test('getCurrentChatId is stable across calls', () => {
@@ -32,3 +35,20 @@ describe('chat id lifecycle', () => {
     expect(rotated).toMatch(/^\d{4}-\d{2}-\d{2}T\d{2}-\d{2}-\d{2}\.\d{3}Z$/)
   })
 })
+
+describe('getProjectDataDir', () => {
+  test('returns a path containing the project basename', () => {
+    setProjectRoot('/tmp/my-project')
+    const dataDir = getProjectDataDir()
+    expect(dataDir).toContain('my-project')
+    expect(dataDir).toContain('projects')
+  })
+
+  test('uses config-dir getConfigDir (not auth re-export)', () => {
+    setProjectRoot('/tmp/test-repo')
+    const dataDir = getProjectDataDir()
+    // Should resolve via config-dir's getConfigDir without pulling in auth.ts
+    const configDir = getConfigDir()
+    expect(dataDir).toContain(configDir)
+  })
+})
diff --git a/cli/src/project-files.ts b/cli/src/project-files.ts
index 99ffa73705..89c94db0fd 100644
--- a/cli/src/project-files.ts
+++ b/cli/src/project-files.ts
@@ -1,7 +1,7 @@
 import { mkdirSync, readdirSync, statSync } from 'fs'
 import path from 'path'
 
-import { getConfigDir } from './utils/auth'
+import { getConfigDir } from './utils/config-dir'
 
 let projectRoot: string | undefined
 let currentChatId: string | undefined