Merge pull request #4352 from pipecat-ai/mb/pyright-fixes-1-per-file

More pyright fixes

changelog/4352.changed.md

@@ -0,0 +1 @@
+- `ToolsSchema(standard_tools=...)` now accepts any `Sequence[FunctionSchema | DirectFunction]` rather than requiring an exact `list` of the union. Callers can pass a narrower `list[FunctionSchema]` (or any other `Sequence`) without the type checker complaining about list invariance.

changelog/4352.fixed.2.md

@@ -0,0 +1 @@
+- Fixed direct-function registration crashing for functions without a docstring. `DirectFunctionWrapper` passed `inspect.getdoc()`'s result to `docstring_parser.parse()`, which raises when the docstring is `None`. Functions now register cleanly whether or not they have a docstring; an empty docstring produces empty description and parameter metadata as expected.

changelog/4352.fixed.md

@@ -0,0 +1 @@
+- Fixed `AssemblyAISTTService`, `CartesiaSTTService`, `GradiumSTTService`, and `SonioxSTTService` crashing the pipeline on transient WebSocket send failures. Each `run_stt` sent audio directly without catching errors, so a single network hiccup mid-stream raised an uncaught exception through `process_frame`. The guards now log a warning and let the connection-state check on the next call handle recovery, matching the pattern used by Deepgram, xAI, Azure, and other push-based STTs.

pyrightconfig.json

@@ -6,9 +6,6 @@
   "exclude": ["**/*_pb2.py", "**/__pycache__"],
   "ignore": [
     "tests",
-    "src/pipecat/adapters/base_llm_adapter.py",
-    "src/pipecat/adapters/schemas/direct_function.py",
-    "src/pipecat/adapters/schemas/tools_schema.py",
     "src/pipecat/adapters/services/anthropic_adapter.py",
     "src/pipecat/adapters/services/aws_nova_sonic_adapter.py",
     "src/pipecat/adapters/services/bedrock_adapter.py",
@@ -23,7 +20,6 @@
     "src/pipecat/audio/filters/aic_filter.py",
     "src/pipecat/audio/filters/krisp_viva_filter.py",
     "src/pipecat/audio/filters/rnnoise_filter.py",
-    "src/pipecat/audio/resamplers/soxr_stream_resampler.py",
     "src/pipecat/audio/turn/smart_turn/local_smart_turn_v2.py",
     "src/pipecat/audio/turn/smart_turn/local_smart_turn_v3.py",
     "src/pipecat/audio/vad/silero.py",
@@ -35,8 +31,6 @@
     "src/pipecat/processors/frameworks/rtvi/processor.py",
     "src/pipecat/processors/frameworks/strands_agents.py",
     "src/pipecat/processors/gstreamer/pipeline_source.py",
-    "src/pipecat/processors/metrics/frame_processor_metrics.py",
-    "src/pipecat/services/ai_service.py",
     "src/pipecat/services/anthropic/llm.py",
     "src/pipecat/services/assemblyai/stt.py",
     "src/pipecat/services/asyncai/tts.py",
@@ -57,7 +51,6 @@
     "src/pipecat/services/deepgram/flux/stt.py",
     "src/pipecat/services/deepgram/sagemaker/stt.py",
     "src/pipecat/services/deepgram/sagemaker/tts.py",
-    "src/pipecat/services/deepgram/stt.py",
     "src/pipecat/services/deepgram/tts.py",
     "src/pipecat/services/elevenlabs/stt.py",
     "src/pipecat/services/elevenlabs/tts.py",
@@ -71,22 +64,18 @@
     "src/pipecat/services/google/tts.py",
     "src/pipecat/services/google/vertex/llm.py",
     "src/pipecat/services/gradium/stt.py",
-    "src/pipecat/services/gradium/tts.py",
     "src/pipecat/services/groq/tts.py",
     "src/pipecat/services/heygen/api_interactive_avatar.py",
     "src/pipecat/services/heygen/base_api.py",
     "src/pipecat/services/heygen/client.py",
     "src/pipecat/services/heygen/video.py",
     "src/pipecat/services/hume/tts.py",
-    "src/pipecat/services/image_service.py",
     "src/pipecat/services/inworld/realtime/llm.py",
     "src/pipecat/services/inworld/tts.py",
     "src/pipecat/services/kokoro/tts.py",
     "src/pipecat/services/llm_service.py",
     "src/pipecat/services/lmnt/tts.py",
-    "src/pipecat/services/mcp_service.py",
     "src/pipecat/services/mem0/memory.py",
-    "src/pipecat/services/mistral/llm.py",
     "src/pipecat/services/mistral/stt.py",
     "src/pipecat/services/mistral/tts.py",
     "src/pipecat/services/moondream/vision.py",
@@ -105,11 +94,9 @@
     "src/pipecat/services/resembleai/tts.py",
     "src/pipecat/services/rime/tts.py",
     "src/pipecat/services/sambanova/llm.py",
-    "src/pipecat/services/sarvam/llm.py",
     "src/pipecat/services/sarvam/stt.py",
     "src/pipecat/services/sarvam/tts.py",
     "src/pipecat/services/simli/video.py",
-    "src/pipecat/services/smallest/stt.py",
     "src/pipecat/services/smallest/tts.py",
     "src/pipecat/services/soniox/stt.py",
     "src/pipecat/services/speechmatics/stt.py",
@@ -118,26 +105,20 @@
     "src/pipecat/services/tavus/video.py",
     "src/pipecat/services/tts_service.py",
     "src/pipecat/services/ultravox/llm.py",
-    "src/pipecat/services/vision_service.py",
     "src/pipecat/services/websocket_service.py",
     "src/pipecat/services/whisper/stt.py",
-    "src/pipecat/services/xai/realtime/events.py",
     "src/pipecat/services/xai/realtime/llm.py",
-    "src/pipecat/services/xai/stt.py",
-    "src/pipecat/services/xai/tts.py",
     "src/pipecat/services/xtts/tts.py",
     "src/pipecat/transports/base_output.py",
     "src/pipecat/transports/daily/transport.py",
     "src/pipecat/transports/heygen/transport.py",
     "src/pipecat/transports/lemonslice/transport.py",
     "src/pipecat/transports/livekit/transport.py",
-    "src/pipecat/transports/local/tk.py",
     "src/pipecat/transports/smallwebrtc/connection.py",
     "src/pipecat/transports/smallwebrtc/request_handler.py",
     "src/pipecat/transports/smallwebrtc/transport.py",
     "src/pipecat/transports/tavus/transport.py",
     "src/pipecat/transports/websocket/client.py",
-    "src/pipecat/transports/websocket/fastapi.py",
     "src/pipecat/transports/websocket/server.py",
     "src/pipecat/transports/whatsapp/client.py"
   ],

src/pipecat/adapters/schemas/direct_function.py

@@ -127,7 +127,7 @@ class BaseDirectFunctionWrapper:
         self.name = self.function.__name__
 
         # Parse docstring for description and parameters
-        docstring = docstring_parser.parse(inspect.getdoc(self.function))
+        docstring = docstring_parser.parse(inspect.getdoc(self.function) or "")
 
         # Get function description
         self.description = (docstring.description or "").strip()

src/pipecat/adapters/schemas/tools_schema.py

@@ -10,6 +10,7 @@ This module provides schemas for managing both standardized function tools
 and custom adapter-specific tools in the Pipecat framework.
 """
 
+from collections.abc import Sequence
 from enum import Enum
 from typing import Any
 
@@ -39,7 +40,7 @@ class ToolsSchema:
 
     def __init__(
         self,
-        standard_tools: list[FunctionSchema | DirectFunction],
+        standard_tools: Sequence[FunctionSchema | DirectFunction],
         custom_tools: dict[AdapterType, list[dict[str, Any]]] | None = None,
     ) -> None:
         """Initialize the tools schema.
@@ -75,7 +76,7 @@ class ToolsSchema:
         return self._standard_tools
 
     @property
-    def custom_tools(self) -> dict[AdapterType, list[dict[str, Any]]]:
+    def custom_tools(self) -> dict[AdapterType, list[dict[str, Any]]] | None:
         """Get the custom tools dictionary.
 
         Returns:

src/pipecat/adapters/services/mistral_adapter.py

@@ -0,0 +1,135 @@
+#
+# Copyright (c) 2024-2026, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+"""Mistral LLM adapter for Pipecat.
+
+Mistral's API uses an OpenAI-compatible interface but imposes three
+conversation-history constraints that OpenAI does not:
+
+1. **Tool messages must be followed by an assistant message.** A ``"tool"``
+   role message that isn't followed by an ``"assistant"`` message is
+   rejected.
+
+2. **Only the initial contiguous system block is permitted.** A
+   ``"system"`` message appearing after any non-system message must be
+   converted to ``"user"``.
+
+3. **A trailing assistant message requires ``prefix=True``.** When the
+   conversation ends on an assistant message, Mistral expects the
+   ``prefix`` flag set so it can continue from that partial reply.
+
+This adapter extends ``OpenAILLMAdapter`` and applies those three fixups
+before the messages reach ``build_chat_completion_params``.
+"""
+
+import copy
+from typing import Any, cast
+
+from openai.types.chat import ChatCompletionMessageParam
+
+from pipecat.adapters.services.open_ai_adapter import OpenAILLMAdapter, OpenAILLMInvocationParams
+from pipecat.processors.aggregators.llm_context import LLMContext
+
+
+class MistralLLMAdapter(OpenAILLMAdapter):
+    """Adapter that transforms messages to satisfy Mistral's API constraints.
+
+    Mistral accepts the OpenAI chat-completions schema but enforces extra
+    rules on conversation history. This adapter extends ``OpenAILLMAdapter``
+    and rewrites the messages produced by the parent to comply with those
+    rules before the request is built.
+    """
+
+    def get_llm_invocation_params(
+        self,
+        context: LLMContext,
+        *,
+        system_instruction: str | None = None,
+        convert_developer_to_user: bool,
+    ) -> OpenAILLMInvocationParams:
+        """Get OpenAI-compatible invocation parameters with Mistral message fixes applied.
+
+        Args:
+            context: The LLM context containing messages, tools, etc.
+            system_instruction: Optional system instruction from service settings
+                or ``run_inference``. Forwarded to the parent adapter.
+            convert_developer_to_user: If True, convert "developer"-role messages
+                to "user"-role messages. Forwarded to the parent adapter.
+
+        Returns:
+            Dictionary of parameters for Mistral's ChatCompletion API, with
+            messages transformed to satisfy Mistral's constraints.
+        """
+        params = super().get_llm_invocation_params(
+            context,
+            system_instruction=system_instruction,
+            convert_developer_to_user=convert_developer_to_user,
+        )
+        params["messages"] = self._transform_messages(list(params["messages"]))
+        return params
+
+    def _transform_messages(
+        self, messages: list[ChatCompletionMessageParam]
+    ) -> list[ChatCompletionMessageParam]:
+        """Transform messages to satisfy Mistral's API constraints.
+
+        Applies three transformation steps in order:
+
+        1. **Insert assistant messages after tool messages** — Any ``"tool"``
+           message not followed by an ``"assistant"`` message gets a minimal
+           ``{"role": "assistant", "content": " "}`` inserted after it.
+
+        2. **Convert non-initial system messages to user** — System messages
+           after the initial contiguous system block are converted to
+           ``"user"``, since Mistral only accepts system messages at the
+           start of a conversation.
+
+        3. **Set prefix on trailing assistant message** — If the final message
+           is an assistant message without a ``prefix`` field, set
+           ``prefix=True`` so Mistral will continue the partial reply.
+
+        Args:
+            messages: List of OpenAI-shaped message dicts.
+
+        Returns:
+            Transformed list of messages satisfying Mistral's constraints.
+        """
+        if not messages:
+            return messages
+
+        # Work on plain dicts: we need to mutate "role" (which OpenAI TypedDict
+        # variants tag with fixed Literals) and to attach Mistral's non-standard
+        # "prefix" field. Cast back on return — the outgoing list is valid for
+        # Mistral's extended schema even though it doesn't fit OpenAI's.
+        msgs: list[dict[str, Any]] = copy.deepcopy([dict(m) for m in messages])
+
+        # Step 1: ensure every "tool" message is followed by an "assistant".
+        insert_at: list[int] = []
+        for i, msg in enumerate(msgs):
+            if msg.get("role") == "tool":
+                is_last = i == len(msgs) - 1
+                if is_last or msgs[i + 1].get("role") != "assistant":
+                    insert_at.append(i + 1)
+        for idx in reversed(insert_at):
+            msgs.insert(idx, {"role": "assistant", "content": " "})
+
+        # Step 2: convert non-initial system messages to "user".
+        # Mistral rejects system messages after any non-system message.
+        first_non_system = next(
+            (i for i, m in enumerate(msgs) if m.get("role") != "system"),
+            len(msgs),
+        )
+        for i in range(first_non_system, len(msgs)):
+            if msgs[i].get("role") == "system":
+                msgs[i]["role"] = "user"
+
+        # Step 3: set prefix on a trailing assistant message so Mistral will
+        # continue it rather than rejecting the turn.
+        last = msgs[-1]
+        if last.get("role") == "assistant" and "prefix" not in last:
+            last["prefix"] = True
+
+        return cast(list[ChatCompletionMessageParam], msgs)

src/pipecat/audio/resamplers/soxr_stream_resampler.py

@@ -68,7 +68,7 @@ class SOXRStreamAudioResampler(BaseAudioResampler):
                 self._soxr_stream.clear()
         self._last_resample_time = current_time
 
-    def _maybe_initialize_sox_stream(self, in_rate: int, out_rate: int):
+    def _maybe_initialize_sox_stream(self, in_rate: int, out_rate: int) -> "soxr.ResampleStream":
         if self._soxr_stream is None:
             self._initialize(in_rate, out_rate)
         else:
@@ -80,6 +80,9 @@ class SOXRStreamAudioResampler(BaseAudioResampler):
                 f"expected {self._in_rate}->{self._out_rate}, got {in_rate}->{out_rate}"
             )
 
+        assert self._soxr_stream is not None
+        return self._soxr_stream
+
     async def resample(self, audio: bytes, in_rate: int, out_rate: int) -> bytes:
         """Resample audio data using soxr.ResampleStream resampler library.
 
@@ -94,8 +97,8 @@ class SOXRStreamAudioResampler(BaseAudioResampler):
         if in_rate == out_rate:
             return audio
 
-        self._maybe_initialize_sox_stream(in_rate, out_rate)
+        stream = self._maybe_initialize_sox_stream(in_rate, out_rate)
         audio_data = np.frombuffer(audio, dtype=np.int16)
-        resampled_audio = self._soxr_stream.resample_chunk(audio_data)
+        resampled_audio = stream.resample_chunk(audio_data)
         result = resampled_audio.astype(np.int16).tobytes()
         return result

src/pipecat/processors/metrics/frame_processor_metrics.py

@@ -66,6 +66,8 @@ class FrameProcessorMetrics(BaseObject):
         Returns:
             The task manager instance for async operations.
         """
+        if self._task_manager is None:
+            raise RuntimeError("task_manager not set; call setup() first")
         return self._task_manager
 
     @property

src/pipecat/services/ai_service.py

@@ -66,8 +66,9 @@ class AIService(FrameProcessor):
         Args:
             model: The name of the AI model to use.
         """
+        model = self._settings.model
         self.set_core_metrics_data(
-            MetricsData(processor=self.name, model=self._settings.model or "")
+            MetricsData(processor=self.name, model=model if isinstance(model, str) else "")
         )
 
     async def start(self, frame: StartFrame):

src/pipecat/services/assemblyai/stt.py

@@ -418,7 +418,7 @@ class AssemblyAISTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text conversion.
 
         Args:
@@ -433,7 +433,11 @@ class AssemblyAISTTService(WebsocketSTTService):
             while len(self._audio_buffer) >= self._chunk_size_bytes:
                 chunk = bytes(self._audio_buffer[: self._chunk_size_bytes])
                 self._audio_buffer = self._audio_buffer[self._chunk_size_bytes :]
-                await self._websocket.send(chunk)
+                try:
+                    await self._websocket.send(chunk)
+                except Exception as e:
+                    logger.warning(f"{self}: send failed: {e}")
+                    break
 
         yield None
 

src/pipecat/services/asyncai/tts.py

@@ -449,7 +449,7 @@ class AsyncAITTSService(WebsocketTTSService):
         await super().on_audio_context_completed(context_id)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Async API websocket endpoint.
 
         Args:
@@ -620,7 +620,7 @@ class AsyncAIHttpTTSService(TTSService):
         self._output_sample_rate = self.sample_rate
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Async's HTTP streaming API.
 
         Args:

src/pipecat/services/aws/stt.py

@@ -196,7 +196,7 @@ class AWSTranscribeSTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data and send to AWS Transcribe.
 
         Args:

src/pipecat/services/azure/stt.py

@@ -191,7 +191,7 @@ class AzureSTTService(STTService):
 
         return changed
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text conversion.
 
         Feeds audio data to the Azure speech recognizer for processing.

src/pipecat/services/cartesia/stt.py

@@ -277,7 +277,7 @@ class CartesiaSTTService(WebsocketSTTService):
             if self._websocket and self._websocket.state is State.OPEN:
                 await self._websocket.send("finalize")
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text transcription.
 
         Args:
@@ -290,7 +290,10 @@ class CartesiaSTTService(WebsocketSTTService):
         if not self._websocket or self._websocket.state is not State.OPEN:
             await self._connect()
 
-        await self._websocket.send(audio)
+        try:
+            await self._websocket.send(audio)
+        except Exception as e:
+            logger.warning(f"{self}: send failed: {e}")
         yield None
 
     async def _connect(self):

src/pipecat/services/cartesia/tts.py

@@ -660,7 +660,7 @@ class CartesiaTTSService(WebsocketTTSService):
             await self._connect_websocket()
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Cartesia's streaming API.
 
         Args:
@@ -873,7 +873,7 @@ class CartesiaHttpTTSService(TTSService):
         await self._close_session()
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Cartesia's HTTP API.
 
         Args:

src/pipecat/services/deepgram/flux/sagemaker/stt.py

@@ -222,7 +222,7 @@ class DeepgramFluxSageMakerSTTService(DeepgramFluxSTTBase):
     # Audio sending and response receiving
     # ------------------------------------------------------------------
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Deepgram Flux for transcription.
 
         Args:

src/pipecat/services/deepgram/flux/stt.py

@@ -354,7 +354,7 @@ class DeepgramFluxSTTService(DeepgramFluxSTTBase, WebsocketService):
     # Audio sending and receiving
     # ------------------------------------------------------------------
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Deepgram Flux for transcription.
 
         Transmits raw audio bytes to the Deepgram Flux API for real-time speech

src/pipecat/services/deepgram/sagemaker/stt.py

@@ -256,7 +256,7 @@ class DeepgramSageMakerSTTService(STTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Deepgram for transcription.
 
         Args:

src/pipecat/services/deepgram/sagemaker/tts.py

@@ -325,7 +325,7 @@ class DeepgramSageMakerTTSService(TTSService):
                 logger.error(f"{self} error sending Flush message: {e}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Deepgram TTS on SageMaker.
 
         Args:

src/pipecat/services/deepgram/stt.py

@@ -514,7 +514,7 @@ class DeepgramSTTService(STTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Deepgram for transcription.
 
         Args:

src/pipecat/services/deepgram/tts.py

@@ -330,7 +330,7 @@ class DeepgramTTSService(WebsocketTTSService):
                 logger.error(f"{self} error sending Flush message: {e}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Deepgram's WebSocket TTS API.
 
         Args:
@@ -441,7 +441,7 @@ class DeepgramHttpTTSService(TTSService):
         return True
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Deepgram's TTS API.
 
         Args:

src/pipecat/services/elevenlabs/stt.py

@@ -370,7 +370,7 @@ class ElevenLabsSTTService(SegmentedSTTService):
         """Handle a transcription result with tracing."""
         await self.stop_processing_metrics()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Transcribe an audio segment using ElevenLabs' STT API.
 
         Args:
@@ -674,7 +674,7 @@ class ElevenLabsRealtimeSTTService(WebsocketSTTService):
                     except Exception as e:
                         logger.warning(f"Failed to send commit: {e}")
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text transcription.
 
         Args:

src/pipecat/services/elevenlabs/tts.py

@@ -889,7 +889,7 @@ class ElevenLabsTTSService(WebsocketTTSService):
             await self._websocket.send(json.dumps(msg))
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using ElevenLabs' streaming WebSocket API.
 
         Args:
@@ -1240,7 +1240,7 @@ class ElevenLabsHttpTTSService(TTSService):
         return word_times
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using ElevenLabs streaming API with timestamps.
 
         Makes a request to the ElevenLabs API to generate audio and timing data.

src/pipecat/services/fish/tts.py

@@ -373,7 +373,7 @@ class FishAudioTTSService(InterruptibleTTSService):
                 await self.push_error(error_msg=f"Unknown error occurred: {e}", exception=e)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Fish Audio's streaming API.
 
         Args:

src/pipecat/services/gladia/stt.py

@@ -461,7 +461,7 @@ class GladiaSTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Run speech-to-text on audio data.
 
         Args:

src/pipecat/services/google/stt.py

@@ -931,7 +931,7 @@ class GoogleSTTService(STTService):
         except Exception as e:
             await self.push_error(error_msg=f"Unknown error occurred: {e}", exception=e)
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process an audio chunk for STT transcription.
 
         Args:

src/pipecat/services/gradium/stt.py

@@ -333,7 +333,7 @@ class GradiumSTTService(WebsocketSTTService):
         except Exception as e:
             logger.warning(f"Failed to send flush: {e}")
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text conversion.
 
         Args:
@@ -350,7 +350,11 @@ class GradiumSTTService(WebsocketSTTService):
             chunk = base64.b64encode(chunk).decode("utf-8")
             msg = {"type": "audio", "audio": chunk}
             if self._websocket and self._websocket.state is State.OPEN:
-                await self._websocket.send(json.dumps(msg))
+                try:
+                    await self._websocket.send(json.dumps(msg))
+                except Exception as e:
+                    logger.warning(f"{self}: send failed: {e}")
+                    break
 
         yield None
 

src/pipecat/services/gradium/tts.py

@@ -356,7 +356,7 @@ class GradiumTTSService(WebsocketTTSService):
                 await self.push_error(error_msg=f"Error: {msg.get('message', msg)}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Gradium's streaming API.
 
         Args:

src/pipecat/services/image_service.py

@@ -57,7 +57,8 @@ class ImageGenService(AIService):
             Frame: Frames containing the generated image (typically ImageRawFrame
                 or URLImageRawFrame).
         """
-        pass
+        raise NotImplementedError
+        yield  # pragma: no cover
 
     async def process_frame(self, frame: Frame, direction: FrameDirection):
         """Process frames for image generation.

src/pipecat/services/inworld/tts.py

@@ -283,7 +283,7 @@ class InworldHttpTTSService(TTSService):
         return (word_times, chunk_end_time)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate TTS audio for the given text.
 
         Args:
@@ -1134,7 +1134,7 @@ class InworldTTSService(WebsocketTTSService):
         await self.send_with_retry(json.dumps(msg), self._report_error)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate TTS audio for the given text using the Inworld WebSocket TTS service.
 
         Args:

src/pipecat/services/lmnt/tts.py

@@ -336,7 +336,7 @@ class LmntTTSService(InterruptibleTTSService):
                     logger.error(f"Invalid JSON message: {message}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate TTS audio from text using LMNT's streaming API.
 
         Args:

src/pipecat/services/mistral/llm.py

@@ -10,8 +10,8 @@ from collections.abc import Sequence
 from dataclasses import dataclass
 
 from loguru import logger
-from openai.types.chat import ChatCompletionMessageParam
 
+from pipecat.adapters.services.mistral_adapter import MistralLLMAdapter
 from pipecat.adapters.services.open_ai_adapter import OpenAILLMInvocationParams
 from pipecat.frames.frames import FunctionCallFromLLM
 from pipecat.services.openai.base_llm import BaseOpenAILLMService
@@ -36,6 +36,8 @@ class MistralLLMService(OpenAILLMService):
     # This value is used by BaseOpenAILLMService when calling the adapter.
     supports_developer_role = False
 
+    adapter_class = MistralLLMAdapter
+
     Settings = MistralLLMSettings
     _settings: Settings
 
@@ -92,60 +94,6 @@ class MistralLLMService(OpenAILLMService):
         logger.debug(f"Creating Mistral client with api {base_url}")
         return super().create_client(api_key, base_url, **kwargs)
 
-    def _apply_mistral_fixups(
-        self, messages: list[ChatCompletionMessageParam]
-    ) -> list[ChatCompletionMessageParam]:
-        """Apply fixups to messages to meet Mistral-specific requirements.
-
-        1. A "tool"-role message must be followed by an assistant message.
-
-        2. "system"-role messages must only appear at the start of a
-           conversation.
-
-        3. Assistant messages must have prefix=True when they are the final
-           message in a conversation (but at no other point).
-
-        Args:
-            messages: The original list of messages.
-
-        Returns:
-            Messages with Mistral prefix requirement applied to final assistant message.
-        """
-        if not messages:
-            return messages
-
-        # Create a copy to avoid modifying the original
-        fixed_messages = [dict(msg) for msg in messages]
-
-        # Ensure all tool responses are followed by an assistant message
-        assistant_insert_indices = []
-        for i, msg in enumerate(fixed_messages):
-            if msg.get("role") == "tool":
-                # If this is the last message or the next message is not assistant
-                if i == len(fixed_messages) - 1 or fixed_messages[i + 1].get("role") != "assistant":
-                    assistant_insert_indices.append(i + 1)
-        for idx in reversed(assistant_insert_indices):
-            fixed_messages.insert(idx, {"role": "assistant", "content": " "})
-
-        # Convert any "system" messages that aren't at the start (i.e., after the initial contiguous block) to "user"
-        first_non_system_idx = next(
-            (i for i, msg in enumerate(fixed_messages) if msg.get("role") != "system"),
-            len(fixed_messages),
-        )
-        for i, msg in enumerate(fixed_messages):
-            if msg.get("role") == "system" and i >= first_non_system_idx:
-                msg["role"] = "user"
-
-        # Get the last message
-        last_message = fixed_messages[-1]
-
-        # Only add prefix=True to the last message if it's an assistant message
-        # and Mistral would otherwise reject it
-        if last_message.get("role") == "assistant" and "prefix" not in last_message:
-            last_message["prefix"] = True
-
-        return fixed_messages
-
     async def run_function_calls(self, function_calls: Sequence[FunctionCallFromLLM]):
         """Execute function calls, filtering out already-completed ones.
 
@@ -208,18 +156,14 @@ class MistralLLMService(OpenAILLMService):
     def build_chat_completion_params(self, params_from_context: OpenAILLMInvocationParams) -> dict:
         """Build parameters for Mistral chat completion request.
 
-        Handles Mistral-specific requirements including:
+        Handles Mistral-specific parameter mapping (``random_seed`` in place
-        - Assistant message prefix requirement for API compatibility
+        of ``seed``). Message-shape fixups required by Mistral are applied
-        - Parameter mapping (random_seed instead of seed)
+        by :class:`MistralLLMAdapter` upstream.
-        - Core completion settings
         """
-        # Apply Mistral's assistant prefix requirement for API compatibility
-        fixed_messages = self._apply_mistral_fixups(params_from_context["messages"])
-
         params = {
             "model": self._settings.model,
             "stream": True,
-            "messages": fixed_messages,
+            "messages": params_from_context["messages"],
             "tools": params_from_context["tools"],
             "tool_choice": params_from_context["tool_choice"],
             "frequency_penalty": self._settings.frequency_penalty,

src/pipecat/services/mistral/stt.py

@@ -185,7 +185,7 @@ class MistralSTTService(STTService):
             if self._connection and not self._connection.is_closed:
                 await self._connection.flush_audio()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Mistral for transcription.
 
         Args:

src/pipecat/services/neuphonic/tts.py

@@ -366,7 +366,7 @@ class NeuphonicTTSService(InterruptibleTTSService):
             await self._websocket.send(json.dumps(msg))
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Neuphonic's streaming API.
 
         Args:
@@ -565,7 +565,7 @@ class NeuphonicHttpTTSService(TTSService):
             return None
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Neuphonic streaming API.
 
         Args:

src/pipecat/services/nvidia/stt.py

@@ -498,7 +498,7 @@ class NvidiaSTTService(STTService):
                     )
                     logger.trace(f"Interim Transcription: [{transcript}]")
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Process audio data for speech-to-text transcription.
 
         Args:
@@ -756,7 +756,7 @@ class NvidiaSegmentedSTTService(SegmentedSTTService):
         """Handle a transcription result with tracing."""
         pass
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Transcribe an audio segment.
 
         Args:

src/pipecat/services/nvidia/tts.py

@@ -526,7 +526,7 @@ class NvidiaTTSService(TTSService):
         )
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using NVIDIA Nemotron Speech TTS.
 
         On the first call for a turn, starts a persistent ``synthesize_online``

src/pipecat/services/openai/stt.py

@@ -415,7 +415,7 @@ class OpenAIRealtimeSTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to the transcription session.
 
         Audio is streamed over the WebSocket. Transcription results arrive

src/pipecat/services/resembleai/tts.py

@@ -431,7 +431,7 @@ class ResembleAITTSService(WebsocketTTSService):
                 await self._connect_websocket()
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Resemble AI's streaming API.
 
         Args:

src/pipecat/services/rime/tts.py

@@ -603,7 +603,7 @@ class RimeTTSService(WebsocketTTSService):
                 self.reset_active_audio_context()
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Rime's streaming API.
 
         Args:
@@ -786,7 +786,7 @@ class RimeHttpTTSService(TTSService):
         return language_to_rime_language(language)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Rime's HTTP API.
 
         Args:
@@ -1142,7 +1142,7 @@ class RimeNonJsonTTSService(InterruptibleTTSService):
                 await self.push_error(error_msg=f"Error: {e}", exception=e)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Rime's streaming API.
 
         Args:

src/pipecat/services/sarvam/llm.py

@@ -83,7 +83,10 @@ class SarvamLLMService(OpenAILLMService):
         if settings is not None:
             default_settings.apply_update(settings)
 
-        self._validate_model(default_settings.model)
+        model = default_settings.model
+        if not isinstance(model, str):
+            raise ValueError("Sarvam LLM requires a non-empty model string.")
+        self._validate_model(model)
 
         super().__init__(
             api_key=api_key,

src/pipecat/services/sarvam/stt.py

@@ -570,7 +570,7 @@ class SarvamSTTService(STTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Sarvam for transcription.
 
         Args:

src/pipecat/services/sarvam/tts.py

@@ -569,7 +569,7 @@ class SarvamHttpTTSService(TTSService):
         await super().start(frame)
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Sarvam AI's API.
 
         Args:
@@ -1192,7 +1192,7 @@ class SarvamTTSService(InterruptibleTTSService):
             logger.warning("WebSocket not ready, cannot send text")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech audio frames from input text using Sarvam TTS.
 
         Sends text over WebSocket for synthesis and yields corresponding audio or status frames.

src/pipecat/services/smallest/stt.py

@@ -247,7 +247,7 @@ class SmallestSTTService(WebsocketSTTService):
                 except Exception as e:
                     logger.warning(f"{self} failed to send finalize: {e}")
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio to the Smallest Pulse WebSocket for transcription.
 
         Args:

src/pipecat/services/smallest/tts.py

@@ -390,7 +390,7 @@ class SmallestTTSService(InterruptibleTTSService):
                 logger.warning(f"{self} unknown message status: {msg}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using Smallest's WebSocket streaming API.
 
         Args:

src/pipecat/services/soniox/stt.py

@@ -402,7 +402,7 @@ class SonioxSTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Send audio data to Soniox STT Service.
 
         Args:
@@ -412,7 +412,10 @@ class SonioxSTTService(WebsocketSTTService):
             Frame: None (transcription results come via WebSocket callbacks).
         """
         if self._websocket and self._websocket.state is State.OPEN:
-            await self._websocket.send(audio)
+            try:
+                await self._websocket.send(audio)
+            except Exception as e:
+                logger.warning(f"{self}: send failed: {e}")
 
         yield None
 

src/pipecat/services/speechmatics/stt.py

@@ -1059,7 +1059,7 @@ class SpeechmaticsSTTService(STTService):
         """Record transcription event for tracing."""
         pass
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Adds audio to the audio buffer and yields None."""
         try:
             if self._client:

src/pipecat/services/stt_service.py

@@ -274,7 +274,7 @@ class STTService(AIService):
         return Language(language)
 
     @abstractmethod
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Run speech-to-text on the provided audio data.
 
         This method must be implemented by subclasses to provide actual speech

src/pipecat/services/tts_service.py

@@ -446,7 +446,7 @@ class TTSService(AIService):
 
     # Converts the text to audio.
     @abstractmethod
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Run text-to-speech synthesis on the provided text.
 
         This method must be implemented by subclasses to provide actual TTS functionality.

src/pipecat/services/vision_service.py

@@ -59,7 +59,8 @@ class VisionService(AIService):
             Frame: Frames containing the vision analysis results, typically TextFrame
             objects with descriptions or answers.
         """
-        pass
+        raise NotImplementedError
+        yield  # pragma: no cover
 
     async def process_frame(self, frame: Frame, direction: FrameDirection):
         """Process frames, handling vision image frames for analysis.

src/pipecat/services/xai/realtime/events.py

@@ -541,18 +541,6 @@ class InputAudioBufferCleared(ServerEvent):
     type: Literal["input_audio_buffer.cleared"]
 
 
-class ResponseCreated(ServerEvent):
-    """Event indicating an assistant response has been created.
-
-    Parameters:
-        type: Event type, always "response.created".
-        response: The created response object.
-    """
-
-    type: Literal["response.created"]
-    response: "Response"
-
-
 class ResponseOutputItemAdded(ServerEvent):
     """Event indicating an output item has been added to a response.
 

src/pipecat/services/xai/stt.py

@@ -209,7 +209,7 @@ class XAISTTService(WebsocketSTTService):
         await super().cancel(frame)
         await self._disconnect()
 
-    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame, None]:
+    async def run_stt(self, audio: bytes) -> AsyncGenerator[Frame | None, None]:
         """Forward raw audio bytes to the xAI STT WebSocket.
 
         Transcription frames are pushed from the receive task, not yielded

src/pipecat/services/xai/tts.py

@@ -188,7 +188,7 @@ class XAIHttpTTSService(TTSService):
             self._session = None
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate speech from text using xAI's TTS API."""
         logger.debug(f"{self}: Generating TTS [{text}]")
 
@@ -466,7 +466,7 @@ class XAITTSService(InterruptibleTTSService):
                 logger.debug(f"{self}: unhandled xAI message type: {msg_type}")
 
     @traced_tts
-    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame, None]:
+    async def run_tts(self, text: str, context_id: str) -> AsyncGenerator[Frame | None, None]:
         """Generate TTS audio from text using xAI's streaming WebSocket API."""
         logger.debug(f"{self}: Generating TTS [{text}]")
 

src/pipecat/transports/local/tk.py

@@ -228,7 +228,7 @@ class TkOutputTransport(BaseOutputTransport):
 
         # This holds a reference to the photo, preventing it from being garbage
         # collected.
-        self._image_label.image = photo
+        self._image_label.image = photo  # type: ignore[attr-defined]
 
 
 class TkLocalTransport(BaseTransport):

src/pipecat/transports/websocket/fastapi.py

@@ -255,7 +255,9 @@ class FastAPIWebsocketInputTransport(BaseInputTransport):
         if self._params.serializer:
             await self._params.serializer.setup(frame)
         if not self._monitor_websocket_task and self._params.session_timeout:
-            self._monitor_websocket_task = self.create_task(self._monitor_websocket())
+            self._monitor_websocket_task = self.create_task(
+                self._monitor_websocket(self._params.session_timeout)
+            )
         await self._client.trigger_client_connected()
         await self.push_frame(ClientConnectedFrame())
         if not self._receive_task:
@@ -322,9 +324,9 @@ class FastAPIWebsocketInputTransport(BaseInputTransport):
         if not self._client.is_closing:
             await self._client.trigger_client_disconnected()
 
-    async def _monitor_websocket(self):
+    async def _monitor_websocket(self, timeout: int):
-        """Wait for self._params.session_timeout seconds, if the websocket is still open, trigger timeout event."""
+        """Wait for ``timeout`` seconds, then trigger the client-timeout event if still open."""
-        await asyncio.sleep(self._params.session_timeout)
+        await asyncio.sleep(timeout)
         await self._client.trigger_client_timeout()