fix(server): handle tool denial interruption #1070

src/utils/queryHelpers.test.ts

@@ -0,0 +1,26 @@
+import { describe, expect, test } from 'bun:test'
+import {
+  createUserInterruptionMessage,
+  INTERRUPT_MESSAGE_FOR_TOOL_USE,
+} from './messages.js'
+import { isResultSuccessful } from './queryHelpers.js'
+
+describe('isResultSuccessful', () => {
+  test('treats user interruption during tool use as a normal terminal result', () => {
+    const interruption = createUserInterruptionMessage({ toolUse: true })
+
+    expect(isResultSuccessful(interruption, 'tool_use')).toBe(true)
+  })
+
+  test('does not treat an ordinary user prompt as successful after tool_use', () => {
+    const ordinaryPrompt = createUserInterruptionMessage({ toolUse: true })
+    ordinaryPrompt.message.content = [
+      {
+        type: 'text',
+        text: `${INTERRUPT_MESSAGE_FOR_TOOL_USE} keep going`,
+      },
+    ]
+
+    expect(isResultSuccessful(ordinaryPrompt, 'tool_use')).toBe(false)
+  })
+})

src/utils/queryHelpers.ts

@@ -27,7 +27,12 @@ import {
   createFileStateCacheWithSizeLimit,
   type FileStateCache,
 } from './fileStateCache.js'
-import { isNotEmptyMessage, normalizeMessages } from './messages.js'
+import {
+  INTERRUPT_MESSAGE,
+  INTERRUPT_MESSAGE_FOR_TOOL_USE,
+  isNotEmptyMessage,
+  normalizeMessages,
+} from './messages.js'
 import { expandPath } from './path.js'
 import type {
   inputSchema as permissionToolInputSchema,
@@ -50,6 +55,7 @@ const ASK_READ_FILE_STATE_CACHE_SIZE = 10
  * Returns true if:
  * - Last message is assistant with text/thinking content
  * - Last message is user with only tool_result blocks
+ * - Last message is a synthetic user interruption
  * - Last message is the user prompt but the API completed with end_turn
  *   (model chose to emit no content blocks)
  */
@@ -78,6 +84,16 @@ export function isResultSuccessful(
     ) {
       return true
     }
+
+    const onlyBlock = Array.isArray(content) ? content[0] : undefined
+    if (
+      content.length === 1 &&
+      onlyBlock?.type === 'text' &&
+      (onlyBlock.text === INTERRUPT_MESSAGE ||
+        onlyBlock.text === INTERRUPT_MESSAGE_FOR_TOOL_USE)
+    ) {
+      return true
+    }
   }
 
   // Carve-out: API completed (message_delta set stop_reason) but yielded