fix(whatsapp): drop status broadcasts and channel newsletters before agent dispatch (#25845)

WhatsApp pseudo-chats (Status updates / Stories, Channels / Newsletters,
broadcast lists) were being routed through the full agent pipeline. A
user's gateway.log showed the agent replying to a contact's Story
('status@broadcast') with 345 chars plus title-generation cost, which
also shows up in the contact's status feed.

Drop these JIDs at _should_process_message() before the policy gate so
they're filtered regardless of dm_policy or allowlist state. Covers:
- status@broadcast (Stories)
- *@newsletter (Channels)
- *@broadcast (broadcast lists, future-proofing)

The bridge.js already filters these on the fromMe outbound path, but
inbound events on self-chat mode skipped that check.

Tests:
- status@broadcast dropped on open policy
- broadcast filter wins over allowlisted senders
- real DMs still pass through
- helper unit cases (case-insensitive, whitespace-tolerant)

26/26 tests/gateway/test_whatsapp_group_gating.py pass; 59/59 adjacent
WhatsApp test suites pass.

gateway/platforms/whatsapp.py

@@ -322,6 +322,26 @@ class WhatsAppAdapter(BasePlatformAdapter):
             return {str(part).strip() for part in raw if str(part).strip()}
         return {part.strip() for part in str(raw).split(",") if part.strip()}
 
+    @staticmethod
+    def _is_broadcast_chat(chat_id: str) -> bool:
+        """True for WhatsApp pseudo-chats that aren't real conversations.
+
+        Covers Status updates (Stories) and Channel/Newsletter broadcasts.
+        These show up as inbound messages on Baileys but the agent should
+        never reply — answering a Story update spams the contact's status
+        feed, and Channel posts aren't addressable in the first place.
+        """
+        if not chat_id:
+            return False
+        cid = chat_id.strip().lower()
+        if cid == "status@broadcast":
+            return True
+        # @broadcast suffix covers status@broadcast plus any future
+        # broadcast-list variants. @newsletter is the Channel JID suffix.
+        if cid.endswith("@broadcast") or cid.endswith("@newsletter"):
+            return True
+        return False
+
     def _is_dm_allowed(self, sender_id: str) -> bool:
         """Check whether a DM from the given sender should be processed."""
         if self._dm_policy == "disabled":
@@ -432,9 +452,16 @@ class WhatsAppAdapter(BasePlatformAdapter):
         return cleaned.strip() or text
 
     def _should_process_message(self, data: Dict[str, Any]) -> bool:
+        chat_id_raw = str(data.get("chatId") or "")
+        # WhatsApp uses pseudo-chats for Status updates (Stories) and
+        # Channel/Newsletter broadcasts. These are not real conversations
+        # and the agent should never reply to them — even in self-chat mode
+        # where the bridge may surface them as "fromMe" events.
+        if self._is_broadcast_chat(chat_id_raw):
+            return False
         is_group = data.get("isGroup", False)
         if is_group:
-            chat_id = str(data.get("chatId") or "")
+            chat_id = chat_id_raw
             if not self._is_group_allowed(chat_id):
                 return False
         else:

tests/gateway/test_whatsapp_group_gating.py

@@ -296,3 +296,78 @@ def test_config_bridges_whatsapp_allow_from(monkeypatch, tmp_path):
     assert config.platforms[Platform.WHATSAPP].extra["allow_from"] == ["6281234567890@s.whatsapp.net"]
     assert __import__("os").environ["WHATSAPP_DM_POLICY"] == "allowlist"
     assert __import__("os").environ["WHATSAPP_ALLOWED_USERS"] == "6281234567890@s.whatsapp.net"
+
+
+# --- Broadcast / status / newsletter pseudo-chats are always dropped ---
+
+
+def test_status_broadcast_chats_are_always_dropped():
+    """Felipe's gateway.log showed the agent replying to status@broadcast
+    (a contact's WhatsApp Story update). These pseudo-chats aren't real
+    conversations and the adapter must drop them regardless of dm_policy.
+    """
+    from gateway.platforms.whatsapp import WhatsAppAdapter
+
+    # Even on the most permissive config — open DMs, no allowlist — Stories
+    # and Channel posts must not reach the agent.
+    adapter = _make_adapter(dm_policy="open")
+
+    # Classic Story update — what Felipe was seeing in production.
+    status_msg = _dm_message(
+        body="[video received]",
+        chatId="status@broadcast",
+        senderId="34612345678@s.whatsapp.net",
+    )
+    assert adapter._should_process_message(status_msg) is False
+
+    # Channel / Newsletter broadcast posts.
+    newsletter_msg = _dm_message(
+        body="check out our latest post",
+        chatId="120363999999999999@newsletter",
+        senderId="120363999999999999@newsletter",
+    )
+    assert adapter._should_process_message(newsletter_msg) is False
+
+
+def test_broadcast_filter_runs_before_allowlist():
+    """A status@broadcast message from an allowlisted sender still drops —
+    we never want to reply to Stories, even from authorized contacts.
+    """
+    adapter = _make_adapter(
+        dm_policy="allowlist",
+        allow_from=["34612345678@s.whatsapp.net"],
+    )
+
+    msg = _dm_message(
+        body="[image received]",
+        chatId="status@broadcast",
+        senderId="34612345678@s.whatsapp.net",
+    )
+    assert adapter._should_process_message(msg) is False
+
+
+def test_real_dm_still_processed_after_broadcast_filter():
+    """Sanity check: the broadcast filter doesn't accidentally drop real DMs."""
+    adapter = _make_adapter(dm_policy="open")
+
+    msg = _dm_message(
+        body="hello",
+        chatId="34612345678@s.whatsapp.net",
+        senderId="34612345678@s.whatsapp.net",
+    )
+    assert adapter._should_process_message(msg) is True
+
+
+def test_is_broadcast_chat_helper_recognizes_common_jids():
+    from gateway.platforms.whatsapp import WhatsAppAdapter
+
+    assert WhatsAppAdapter._is_broadcast_chat("status@broadcast") is True
+    assert WhatsAppAdapter._is_broadcast_chat("STATUS@BROADCAST") is True
+    assert WhatsAppAdapter._is_broadcast_chat("  status@broadcast  ") is True
+    assert WhatsAppAdapter._is_broadcast_chat("120363999999999999@newsletter") is True
+    assert WhatsAppAdapter._is_broadcast_chat("1234@broadcast") is True  # broadcast list
+    # Real chats must not match.
+    assert WhatsAppAdapter._is_broadcast_chat("34612345678@s.whatsapp.net") is False
+    assert WhatsAppAdapter._is_broadcast_chat("120363001234567890@g.us") is False
+    assert WhatsAppAdapter._is_broadcast_chat("") is False
+    assert WhatsAppAdapter._is_broadcast_chat(None) is False  # type: ignore[arg-type]