fix(v5): recognize conversation depth errors (#2957)

Backport of #2881.\n\nOriginal commit: f68e52251c

Co-authored-by: Felipe Bermudez <felipeberm@gmail.com>

.changeset/deep-conversations-start.md

@@ -0,0 +1,5 @@
+---
+"@docsearch/react": patch
+---
+
+Recognize current Agent Studio conversation-depth error messages.

packages/docsearch-react/src/utils/__tests__/ai.test.ts

@@ -10,10 +10,47 @@ import {
   getSearchToolQueries,
   isAIToolPart,
   isAlgoliaMCPSearchOutputPart,
+  isThreadDepthError,
   sanitizeMessagesForRequest,
   getMessageContent,
 } from '../ai';
 
+describe('isThreadDepthError', () => {
+  it('detects AI-217 regardless of casing', () => {
+    expect(isThreadDepthError(new Error('AI-217: limit reached'))).toBe(true);
+    expect(isThreadDepthError(new Error('prefix ai-217 suffix'))).toBe(true);
+  });
+
+  it('detects conversation depth phrasing', () => {
+    expect(
+      isThreadDepthError(
+        new Error(
+          "You've hit the max conversation depth (4 messages), start a new conversation."
+        )
+      )
+    ).toBe(true);
+    expect(
+      isThreadDepthError(new Error('Maximum conversation depth reached.'))
+    ).toBe(true);
+  });
+
+  it('detects conversation depth in a JSON-shaped error message', () => {
+    expect(
+      isThreadDepthError(
+        new Error(
+          JSON.stringify({ message: 'Maximum conversation depth reached.' })
+        )
+      )
+    ).toBe(true);
+  });
+
+  it('ignores unrelated errors', () => {
+    expect(isThreadDepthError()).toBe(false);
+    expect(isThreadDepthError(new Error('Network failed'))).toBe(false);
+    expect(isThreadDepthError(new Error('AI-214: rate limit'))).toBe(false);
+  });
+});
+
 function message(id: string, parts: AIMessagePart[]): AIMessage {
   return {
     id,

packages/docsearch-react/src/utils/ai.ts

@@ -122,11 +122,11 @@ export const getMessageContent = (message: AIMessage | null): string =>
     .map((part) => part.text)
     .join('\n\n');
 
-/** Helper function to check if error is a thread depth error (AI-217). */
+/** Helper function to check if an error reports the conversation depth limit. */
 export function isThreadDepthError(error?: Error): boolean {
   if (!error) return false;
 
-  return error.message?.includes('AI-217') || false;
+  return /(?:ai-217|conversation\s+depth)/i.test(error.message ?? '');
 }
 
 export const EMPTY_TOOLS: Readonly<ToolCalls> = Object.freeze({});