fix(discord): skip auto-threading reply messages

gateway/platforms/discord.py

@@ -2285,6 +2285,26 @@ class DiscordAdapter(BasePlatformAdapter):
         from gateway.platforms.base import resolve_channel_prompt
         return resolve_channel_prompt(self.config.extra, channel_id, parent_id)
 
+    def _discord_require_mention(self) -> bool:
+        """Return whether Discord channel messages require a bot mention."""
+        configured = self.config.extra.get("require_mention")
+        if configured is not None:
+            if isinstance(configured, str):
+                return configured.lower() not in ("false", "0", "no", "off")
+            return bool(configured)
+        return os.getenv("DISCORD_REQUIRE_MENTION", "true").lower() not in ("false", "0", "no", "off")
+
+    def _discord_free_response_channels(self) -> set:
+        """Return Discord channel IDs where no bot mention is required."""
+        raw = self.config.extra.get("free_response_channels")
+        if raw is None:
+            raw = os.getenv("DISCORD_FREE_RESPONSE_CHANNELS", "")
+        if isinstance(raw, list):
+            return {str(part).strip() for part in raw if str(part).strip()}
+        if isinstance(raw, str) and raw.strip():
+            return {part.strip() for part in raw.split(",") if part.strip()}
+        return set()
+
     def _thread_parent_channel(self, channel: Any) -> Any:
         """Return the parent text channel when invoked from a thread."""
         return getattr(channel, "parent", None) or channel
@@ -2745,12 +2765,11 @@ class DiscordAdapter(BasePlatformAdapter):
                 logger.debug("[%s] Ignoring message in ignored channel: %s", self.name, channel_ids)
                 return
 
-            free_channels_raw = os.getenv("DISCORD_FREE_RESPONSE_CHANNELS", "")
+            free_channels = self._discord_free_response_channels()
-            free_channels = {ch.strip() for ch in free_channels_raw.split(",") if ch.strip()}
             if parent_channel_id:
                 channel_ids.add(parent_channel_id)
 
-            require_mention = os.getenv("DISCORD_REQUIRE_MENTION", "true").lower() not in ("false", "0", "no")
+            require_mention = self._discord_require_mention()
             # Voice-linked text channels act as free-response while voice is active.
             # Only the exact bound channel gets the exemption, not sibling threads.
             voice_linked_ids = {str(ch_id) for ch_id in self._voice_text_channels.values()}
@@ -2780,7 +2799,8 @@ class DiscordAdapter(BasePlatformAdapter):
             no_thread_channels = {ch.strip() for ch in no_thread_channels_raw.split(",") if ch.strip()}
             skip_thread = bool(channel_ids & no_thread_channels) or is_free_channel
             auto_thread = os.getenv("DISCORD_AUTO_THREAD", "true").lower() in ("true", "1", "yes")
-            if auto_thread and not skip_thread and not is_voice_linked_channel:
+            is_reply_message = getattr(message, "type", None) == discord.MessageType.reply
+            if auto_thread and not skip_thread and not is_voice_linked_channel and not is_reply_message:
                 thread = await self._auto_create_thread(message)
                 if thread:
                     is_thread = True

tests/gateway/test_discord_free_response.py

@@ -96,7 +96,7 @@ def adapter(monkeypatch):
     return adapter
 
 
-def make_message(*, channel, content: str, mentions=None):
+def make_message(*, channel, content: str, mentions=None, msg_type=None):
     author = SimpleNamespace(id=42, display_name="Jezza", name="Jezza")
     return SimpleNamespace(
         id=123,
@@ -107,6 +107,7 @@ def make_message(*, channel, content: str, mentions=None):
         created_at=datetime.now(timezone.utc),
         channel=channel,
         author=author,
+        type=msg_type if msg_type is not None else discord_platform.discord.MessageType.default,
     )
 
 
@@ -204,6 +205,21 @@ async def test_discord_free_response_channel_overrides_mention_requirement(adapt
     assert event.text == "allowed without mention"
 
 
+@pytest.mark.asyncio
+async def test_discord_free_response_channel_can_come_from_config_extra(adapter, monkeypatch):
+    monkeypatch.delenv("DISCORD_REQUIRE_MENTION", raising=False)
+    monkeypatch.delenv("DISCORD_FREE_RESPONSE_CHANNELS", raising=False)
+    adapter.config.extra["free_response_channels"] = ["789", "999"]
+
+    message = make_message(channel=FakeTextChannel(channel_id=789), content="allowed from config")
+
+    await adapter._handle_message(message)
+
+    adapter.handle_message.assert_awaited_once()
+    event = adapter.handle_message.await_args.args[0]
+    assert event.text == "allowed from config"
+
+
 @pytest.mark.asyncio
 async def test_discord_forum_parent_in_free_response_list_allows_forum_thread(adapter, monkeypatch):
     monkeypatch.setenv("DISCORD_REQUIRE_MENTION", "true")
@@ -276,6 +292,31 @@ async def test_discord_auto_thread_enabled_by_default(adapter, monkeypatch):
     assert event.source.thread_id == "999"
 
 
+@pytest.mark.asyncio
+async def test_discord_reply_message_skips_auto_thread(adapter, monkeypatch):
+    """Quote-replies should stay in-channel instead of trying to create a thread."""
+    monkeypatch.delenv("DISCORD_AUTO_THREAD", raising=False)
+    monkeypatch.setenv("DISCORD_REQUIRE_MENTION", "true")
+    monkeypatch.setenv("DISCORD_FREE_RESPONSE_CHANNELS", "123")
+
+    adapter._auto_create_thread = AsyncMock()
+
+    message = make_message(
+        channel=FakeTextChannel(channel_id=123),
+        content="reply without mention",
+        msg_type=discord_platform.discord.MessageType.reply,
+    )
+
+    await adapter._handle_message(message)
+
+    adapter._auto_create_thread.assert_not_awaited()
+    adapter.handle_message.assert_awaited_once()
+    event = adapter.handle_message.await_args.args[0]
+    assert event.text == "reply without mention"
+    assert event.source.chat_id == "123"
+    assert event.source.chat_type == "group"
+
+
 @pytest.mark.asyncio
 async def test_discord_auto_thread_can_be_disabled(adapter, monkeypatch):
     """Setting auto_thread to false skips thread creation."""