Support Slack thread targets in send_message

tests/tools/test_send_message_tool.py

@@ -858,6 +858,12 @@ def test_private_channel_id_is_explicit(self):
     def test_dm_id_is_explicit(self):
         assert _parse_target_ref("slack", "D123ABCDEF")[2] is True
 
+    def test_channel_id_with_thread_ts_is_explicit(self):
+        chat_id, thread_id, is_explicit = _parse_target_ref("slack", "C0B0QV5434G:1777520157.319429")
+        assert chat_id == "C0B0QV5434G"
+        assert thread_id == "1777520157.319429"
+        assert is_explicit is True
+
     def test_user_id_is_not_explicit(self):
         """Slack user IDs (U...) and workspace IDs (W...) are NOT explicit send
         targets. chat.postMessage rejects them — a DM must be opened first via
@@ -875,6 +881,7 @@ def test_lowercase_or_short_id_is_not_explicit(self):
         assert _parse_target_ref("slack", "c0b0qv5434g")[2] is False
         assert _parse_target_ref("slack", "C123")[2] is False
         assert _parse_target_ref("slack", "X0B0QV5434G")[2] is False
+        assert _parse_target_ref("slack", "C0B0QV5434G:not-a-ts")[2] is False
 
     def test_slack_id_not_explicit_for_other_platforms(self):
         assert _parse_target_ref("discord", "C0B0QV5434G")[2] is False

tools/send_message_tool.py

@@ -26,7 +26,7 @@
 # because the API requires a conversation ID. To DM a user you must first call
 # conversations.open to obtain a D... ID. Without this gate, Slack IDs fall
 # through to channel-name resolution, which only matches by name and fails.
-_SLACK_TARGET_RE = re.compile(r"^\s*([CGD][A-Z0-9]{8,})\s*$")
+_SLACK_TARGET_RE = re.compile(r"^\s*([CGD][A-Z0-9]{8,})(?::([0-9]+(?:\.[0-9]+)?))?\s*$")
 _WEIXIN_TARGET_RE = re.compile(r"^\s*((?:wxid|gh|v\d+|wm|wb)_[A-Za-z0-9_-]+|[A-Za-z0-9._-]+@chatroom|filehelper)\s*$")
 _YUANBAO_TARGET_RE = re.compile(r"^\s*((?:group|direct):[^:]+)\s*$")
 # Discord snowflake IDs are numeric, same regex pattern as Telegram topic targets.
@@ -338,7 +338,7 @@ def _parse_target_ref(platform_name: str, target_ref: str):
     if platform_name == "slack":
         match = _SLACK_TARGET_RE.fullmatch(target_ref)
         if match:
-            return match.group(1), None, True
+            return match.group(1), match.group(2), True
     if platform_name == "weixin":
         match = _WEIXIN_TARGET_RE.fullmatch(target_ref)
         if match:
@@ -589,7 +589,7 @@ async def _send_to_platform(platform, pconfig, chat_id, message, thread_id=None,
     last_result = None
     for chunk in chunks:
         if platform == Platform.SLACK:
-            result = await _send_slack(pconfig.token, chat_id, chunk)
+            result = await _send_slack(pconfig.token, chat_id, chunk, thread_id=thread_id)
         elif platform == Platform.WHATSAPP:
             result = await _send_whatsapp(pconfig.extra, chat_id, chunk)
         elif platform == Platform.SIGNAL:
@@ -980,7 +980,7 @@ async def _send_discord(token, chat_id, message, thread_id=None, media_files=Non
         return _error(f"Discord send failed: {e}")
 
 
-async def _send_slack(token, chat_id, message):
+async def _send_slack(token, chat_id, message, thread_id=None):
     """Send via Slack Web API."""
     try:
         import aiohttp
@@ -994,6 +994,8 @@ async def _send_slack(token, chat_id, message):
         headers = {"Authorization": f"Bearer {token}", "Content-Type": "application/json"}
         async with aiohttp.ClientSession(timeout=aiohttp.ClientTimeout(total=30), **_sess_kw) as session:
             payload = {"channel": chat_id, "text": message, "mrkdwn": True}
+            if thread_id:
+                payload["thread_ts"] = str(thread_id)
             async with session.post(url, headers=headers, json=payload, **_req_kw) as resp:
                 data = await resp.json()
                 if data.get("ok"):