fix: disallow partial overrides of context args in agent chat_stream()

mwbrooks · mwbrooks · commit 724ea5ff7940 · 2026-02-11T20:48:24.000-08:00
diff --git a/slack_bolt/agent/agent.py b/slack_bolt/agent/agent.py
@@ -58,6 +58,11 @@ def chat_stream(
         Returns:
             A new ``ChatStream`` instance.
         """
+        provided = [arg for arg in (channel, thread_ts, recipient_team_id, recipient_user_id) if arg is not None]
+        if provided and len(provided) < 4:
+            raise ValueError(
+                "Either provide all of channel, thread_ts, recipient_team_id, and recipient_user_id, or none of them"
+            )
         resolved_channel = channel or self._channel_id
         resolved_thread_ts = thread_ts or self._thread_ts
         if resolved_channel is None:
diff --git a/slack_bolt/agent/async_agent.py b/slack_bolt/agent/async_agent.py
@@ -55,6 +55,11 @@ async def chat_stream(
         Returns:
             A new ``AsyncChatStream`` instance.
         """
+        provided = [arg for arg in (channel, thread_ts, recipient_team_id, recipient_user_id) if arg is not None]
+        if provided and len(provided) < 4:
+            raise ValueError(
+                "Either provide all of channel, thread_ts, recipient_team_id, and recipient_user_id, or none of them"
+            )
         resolved_channel = channel or self._channel_id
         resolved_thread_ts = thread_ts or self._thread_ts
         if resolved_channel is None:
diff --git a/tests/scenario_tests/test_events_agent.py b/tests/scenario_tests/test_events_agent.py
@@ -106,6 +106,19 @@ def test_agent_chat_stream_overrides_context_defaults(self):
         )
         assert stream is not None
 
+    def test_agent_chat_stream_rejects_partial_overrides(self):
+        """Passing only some of the four context args raises ValueError."""
+        client = MagicMock(spec=WebClient)
+        agent = BoltAgentDirect(
+            client=client,
+            channel_id="C111",
+            thread_ts="1234567890.123456",
+            team_id="T111",
+            user_id="W222",
+        )
+        with pytest.raises(ValueError, match="Either provide all of"):
+            agent.chat_stream(channel="C999")
+
     def test_agent_chat_stream_passes_extra_kwargs(self):
         """Extra kwargs are forwarded to WebClient.chat_stream()."""
         client = MagicMock(spec=WebClient)
diff --git a/tests/scenario_tests_async/test_events_agent.py b/tests/scenario_tests_async/test_events_agent.py
@@ -124,6 +124,20 @@ async def test_agent_chat_stream_overrides_context_defaults(self):
         )
         assert stream is not None
 
+    @pytest.mark.asyncio
+    async def test_agent_chat_stream_rejects_partial_overrides(self):
+        """Passing only some of the four context args raises ValueError."""
+        client = MagicMock(spec=AsyncWebClient)
+        agent = AsyncBoltAgent(
+            client=client,
+            channel_id="C111",
+            thread_ts="1234567890.123456",
+            team_id="T111",
+            user_id="W222",
+        )
+        with pytest.raises(ValueError, match="Either provide all of"):
+            await agent.chat_stream(channel="C999")
+
     @pytest.mark.asyncio
     async def test_agent_chat_stream_passes_extra_kwargs(self):
         """Extra kwargs are forwarded to AsyncWebClient.chat_stream()."""
