fix(provider): strip think tags for MiniMax-M3 and other OpenAI-compatible models (#2330)

* fix(provider): strip think tags for MiniMax-M3 and other OpenAI-compatible models MiniMax-M3 (and other OpenAI-compatible providers) emit chain-of-thought reasoning directly in the content field wrapped in tags, instead of using a separate reasoning_content field or the legacy CRETIRE_REASONING markers. The existing remove_think logic only handled CRETIRE_* tags, so think blocks leaked into user-visible output even when remove_think was enabled. - Add _ThinkStripState: a stateful filter that correctly handles tags split across streaming chunk boundaries. - Add _strip_think classmethod with regex patterns for both and CRETIRE_* tags. - Wire think_state into invoke_llm_stream so deltas are filtered before reaching the accumulator. - Add remove_think safety net in _StreamAccumulator so the final message from tool-call rounds also gets stripped. - Fix remove_think resolution to use defensive nested .get() so pipelines missing output.misc don't raise AttributeError. * fix(litellmchat): add missing _CLOSE_TAG class attribute on _ThinkStripState * fix(provider): handle think stripping across LiteLLM paths --------- Co-authored-by: WangCham <651122857@qq.com>
2026-07-16 17:36:07 +00:00 · 2026-07-15 10:54:41 +08:00
parent bd35b793e1
commit c53b800267
4 changed files with 431 additions and 18 deletions
@@ -279,6 +279,122 @@ class TestInvokeLLMStreamUsage:

        assert query.variables['_stream_usage']['total_tokens'] == 12

+    @pytest.mark.asyncio
+    async def test_stream_removes_leading_think_across_chunks(self):
+        """A leading think block split across chunks must be removed."""
+        import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
+        import langbot_plugin.api.entities.builtin.provider.message as provider_message
+
+        mock_ap = Mock()
+        mock_ap.tool_mgr = Mock()
+        mock_ap.tool_mgr.generate_tools_for_openai = AsyncMock(return_value=None)
+        requester = litellmchat.LiteLLMRequester(ap=mock_ap, config={})
+        model = MockRuntimeModel('minimax-m3', 'test-api-key')
+
+        chunks = [
+            self._make_chunk(content='<thi'),
+            self._make_chunk(content='nk>hidden'),
+            self._make_chunk(content=' reasoning</thi'),
+            self._make_chunk(content='nk>Visible answer', finish_reason='stop'),
+        ]
+
+        async def _aiter(*args, **kwargs):
+            for c in chunks:
+                yield c
+
+        query = Mock(spec=pipeline_query.Query)
+        query.variables = {}
+        messages = [provider_message.Message(role='user', content='Hi')]
+
+        with patch.object(litellmchat, 'acompletion', new=AsyncMock(side_effect=lambda **kw: _aiter())):
+            collected = [
+                chunk
+                async for chunk in requester.invoke_llm_stream(
+                    query=query,
+                    model=model,
+                    messages=messages,
+                    remove_think=True,
+                )
+            ]
+
+        assert ''.join(chunk.content or '' for chunk in collected) == 'Visible answer'
+
+    @pytest.mark.asyncio
+    async def test_stream_removes_initial_orphan_think_close(self):
+        """Initial reasoning content without an open tag is removed until </think>."""
+        import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
+        import langbot_plugin.api.entities.builtin.provider.message as provider_message
+
+        mock_ap = Mock()
+        mock_ap.tool_mgr = Mock()
+        mock_ap.tool_mgr.generate_tools_for_openai = AsyncMock(return_value=None)
+        requester = litellmchat.LiteLLMRequester(ap=mock_ap, config={})
+        model = MockRuntimeModel('minimax-m3', 'test-api-key')
+
+        chunks = [
+            self._make_chunk(content='hidden reasoning'),
+            self._make_chunk(content=' still hidden</thi'),
+            self._make_chunk(content='nk>Visible answer', finish_reason='stop'),
+        ]
+
+        async def _aiter(*args, **kwargs):
+            for c in chunks:
+                yield c
+
+        query = Mock(spec=pipeline_query.Query)
+        query.variables = {}
+        messages = [provider_message.Message(role='user', content='Hi')]
+
+        with patch.object(litellmchat, 'acompletion', new=AsyncMock(side_effect=lambda **kw: _aiter())):
+            collected = [
+                chunk
+                async for chunk in requester.invoke_llm_stream(
+                    query=query,
+                    model=model,
+                    messages=messages,
+                    remove_think=True,
+                )
+            ]
+
+        assert ''.join(chunk.content or '' for chunk in collected) == 'Visible answer'
+
+    @pytest.mark.asyncio
+    async def test_stream_removes_non_leading_think_content(self):
+        """A think block in the answer body is removed with its content."""
+        import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
+        import langbot_plugin.api.entities.builtin.provider.message as provider_message
+
+        mock_ap = Mock()
+        mock_ap.tool_mgr = Mock()
+        mock_ap.tool_mgr.generate_tools_for_openai = AsyncMock(return_value=None)
+        requester = litellmchat.LiteLLMRequester(ap=mock_ap, config={})
+        model = MockRuntimeModel('gpt-4o', 'test-api-key')
+
+        chunks = [
+            self._make_chunk(content='Use <think>x</think> as an XML-like example.', finish_reason='stop'),
+        ]
+
+        async def _aiter(*args, **kwargs):
+            for c in chunks:
+                yield c
+
+        query = Mock(spec=pipeline_query.Query)
+        query.variables = {}
+        messages = [provider_message.Message(role='user', content='Hi')]
+
+        with patch.object(litellmchat, 'acompletion', new=AsyncMock(side_effect=lambda **kw: _aiter())):
+            collected = [
+                chunk
+                async for chunk in requester.invoke_llm_stream(
+                    query=query,
+                    model=model,
+                    messages=messages,
+                    remove_think=True,
+                )
+            ]
+
+        assert ''.join(chunk.content or '' for chunk in collected) == 'Use  as an XML-like example.'
+
    @pytest.mark.asyncio
    async def test_stream_tool_call_delta_missing_id_and_name(self):
        """LiteLLM may stream tool-call argument deltas with id/name set to None."""
@@ -482,6 +598,38 @@ class TestProcessThinkingContent:
        result = requester._process_thinking_content(content, None, remove_think=True)
        assert result == 'The answer is 42.'

+    def test_remove_leading_think_tag(self):
+        """Test removing a leading <think> block when remove_think=True"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        content = '<think>Let me think...</think> The answer is 42.'
+        result = requester._process_thinking_content(content, None, remove_think=True)
+        assert result == 'The answer is 42.'
+
+    def test_remove_non_leading_think_tag(self):
+        """Test removing <think> and its content in the answer body"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        content = 'Use <think>example</think> in the document.'
+        result = requester._process_thinking_content(content, None, remove_think=True)
+        assert result == 'Use  in the document.'
+
+    def test_remove_initial_orphan_think_close(self):
+        """Test removing leading reasoning content when only </think> is visible"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        content = 'hidden reasoning</think> Visible answer.'
+        result = requester._process_thinking_content(content, None, remove_think=True)
+        assert result == 'Visible answer.'
+
+    def test_remove_multiple_think_tags(self):
+        """Test removing multiple <think> blocks"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        content = '<think>hidden</think> Keep <think>example</think>.'
+        result = requester._process_thinking_content(content, None, remove_think=True)
+        assert result == 'Keep .'
+
    def test_preserve_thinking_markers(self):
        """Test preserving thinking markers when remove_think=False"""
        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
@@ -491,6 +639,20 @@ class TestProcessThinkingContent:
        assert 'CRETIRE_REASONING_BEGINk' in result
        assert 'The answer is 42.' in result

+    def test_preserve_reasoning_content_when_remove_think_false(self):
+        """Test showing separate reasoning_content when remove_think=False"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        result = requester._process_thinking_content('The answer is 42.', 'Let me think...', remove_think=False)
+        assert result == '<think>\nLet me think...\n</think>\nThe answer is 42.'
+
+    def test_hide_reasoning_content_when_remove_think_true(self):
+        """Test hiding separate reasoning_content when remove_think=True"""
+        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
+
+        result = requester._process_thinking_content('The answer is 42.', 'Let me think...', remove_think=True)
+        assert result == 'The answer is 42.'
+
    def test_empty_content(self):
        """Test empty content"""
        requester = litellmchat.LiteLLMRequester(ap=Mock(), config={})
@@ -163,6 +163,51 @@ def test_stream_accumulator_merges_fragmented_tool_call_arguments():
    assert final_msg.tool_calls[0].function.arguments == '{"command":"pwd"}'


+def test_stream_accumulator_strips_leading_think_from_tool_round_content():
+    accumulator = _StreamAccumulator(
+        msg_sequence=3,
+        initial_content='I will search for LangBot.',
+        remove_think=True,
+    )
+
+    assert accumulator.add(provider_message.MessageChunk(role='assistant', content='<thi')) is None
+    assert accumulator.add(provider_message.MessageChunk(role='assistant', content='nk>hidden')) is None
+    emitted = accumulator.add(
+        provider_message.MessageChunk(
+            role='assistant',
+            content=' reasoning</think>Here is the answer.',
+            is_final=True,
+        )
+    )
+
+    assert emitted is not None
+    assert emitted.content == 'I will search for LangBot.Here is the answer.'
+    assert '<think>' not in emitted.content
+    assert 'hidden reasoning' not in emitted.content
+
+
+def test_stream_accumulator_strips_initial_orphan_think_close_from_tool_round_content():
+    accumulator = _StreamAccumulator(
+        msg_sequence=3,
+        initial_content='I will search for LangBot.',
+        remove_think=True,
+    )
+
+    assert accumulator.add(provider_message.MessageChunk(role='assistant', content='hidden reasoning')) is None
+    emitted = accumulator.add(
+        provider_message.MessageChunk(
+            role='assistant',
+            content=' still hidden</think>Here is the answer.',
+            is_final=True,
+        )
+    )
+
+    assert emitted is not None
+    assert emitted.content == 'I will search for LangBot.Here is the answer.'
+    assert '</think>' not in emitted.content
+    assert 'hidden reasoning' not in emitted.content
+
+
@pytest.mark.asyncio
 async def test_localagent_uses_exec_for_exact_calculation():
    provider = RecordingProvider()