Feature Request: Add thread/topic title support in Reply Message API

Feature Request

API area: IM v1 — Messages / Threads

Problem

When creating threads (话题) in P2P (1:1) chats via the Reply Message API (POST /im/v1/messages/:message_id/reply with reply_in_thread: true), the resulting thread window always displays a generic title "话题" (Topic). There is currently:

1. No parameter in the Reply Message API to set a custom thread title/name
2. No dedicated API endpoint to update a thread's title after creation
3. No way for users to edit thread titles in the Feishu PC/mobile client for P2P chats

This contrasts with 话题群 (topic groups), where topic titles are fully supported.

Use Case

We run a multi-agent AI assistant system built on the Feishu Open Platform. Each agent creates branched thread windows for parallel conversations via the Reply API. When a user has 5+ active threads with the same bot, they all show "话题" — making it impossible to distinguish between them without opening each one.

Proposed Solution

1. Add an optional thread_name field to ReplyMessageRequestBody for the Reply Message API:

   {
     "content": "...",
     "msg_type": "text",
     "reply_in_thread": true,
     "thread_name": "SSH Security Hardening"
   }
   

2. Add a PATCH endpoint for updating thread titles:

   PATCH /im/v1/threads/:thread_id
   { "name": "Updated Thread Title" }
   

3. Enable client-side editing of thread titles in P2P chats (currently only available in topic groups).

Impact

Thread naming would significantly improve UX for bot-heavy workflows where users maintain multiple concurrent conversation branches. The thread_id (omt_*) infrastructure already exists — this request is about exposing title metadata for it.

Thank you for considering this enhancement.

Start by locating the IM v1 Reply Message API definition and its ReplyMessageRequestBody, then trace how thread-related fields are represented in the SDK. Compare the requested thread_name field and PATCH /im/v1/threads/:thread_id operation with the existing API surface; done requires the SDK to expose the agreed thread-title operations and corresponding request data.