Add xAI HTTP TTS service

Reworks the xAI TTS integration from #4031 with consistency fixes:
- Rename to XAIHttpTTSService (leaves room for future WebSocket service)
- Add proper language map with all 20 supported xAI languages
- Remove unnecessary deprecated InputParams/params (new service, nothing to deprecate)
- Add encoding as a constructor parameter
- Use Language.EN enum instead of string for default language
- Linting fixes

changelog/4031.added.md

@@ -0,0 +1 @@
+- Added `XAIHttpTTSService` for text-to-speech using xAI's HTTP TTS API.

examples/foundational/07e-interruptible-xai.py

@@ -0,0 +1,129 @@
+#
+# Copyright (c) 2024-2026, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+import os
+
+import aiohttp
+from dotenv import load_dotenv
+from loguru import logger
+
+from pipecat.audio.vad.silero import SileroVADAnalyzer
+from pipecat.frames.frames import LLMRunFrame
+from pipecat.pipeline.pipeline import Pipeline
+from pipecat.pipeline.runner import PipelineRunner
+from pipecat.pipeline.task import PipelineParams, PipelineTask
+from pipecat.processors.aggregators.llm_context import LLMContext
+from pipecat.processors.aggregators.llm_response_universal import (
+    LLMContextAggregatorPair,
+    LLMUserAggregatorParams,
+)
+from pipecat.runner.types import RunnerArguments
+from pipecat.runner.utils import create_transport
+from pipecat.services.deepgram.stt import DeepgramSTTService
+from pipecat.services.grok.llm import GrokLLMService
+from pipecat.services.xai.tts import XAIHttpTTSService
+from pipecat.transports.base_transport import BaseTransport, TransportParams
+from pipecat.transports.daily.transport import DailyParams
+from pipecat.transports.websocket.fastapi import FastAPIWebsocketParams
+
+load_dotenv(override=True)
+
+# We use lambdas to defer transport parameter creation until the transport
+# type is selected at runtime.
+transport_params = {
+    "daily": lambda: DailyParams(
+        audio_in_enabled=True,
+        audio_out_enabled=True,
+    ),
+    "twilio": lambda: FastAPIWebsocketParams(
+        audio_in_enabled=True,
+        audio_out_enabled=True,
+    ),
+    "webrtc": lambda: TransportParams(
+        audio_in_enabled=True,
+        audio_out_enabled=True,
+    ),
+}
+
+
+async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
+    logger.info(f"Starting bot")
+
+    async with aiohttp.ClientSession() as session:
+        stt = DeepgramSTTService(api_key=os.getenv("DEEPGRAM_API_KEY"))
+
+        tts = XAIHttpTTSService(
+            api_key=os.getenv("GROK_API_KEY"),
+            aiohttp_session=session,
+            settings=XAIHttpTTSService.Settings(
+                voice="eve",
+            ),
+        )
+
+        llm = GrokLLMService(
+            api_key=os.getenv("GROK_API_KEY"),
+            settings=GrokLLMService.Settings(
+                system_instruction="You are a helpful assistant in a voice conversation. Your responses will be spoken aloud, so avoid emojis, bullet points, or other formatting that can't be spoken. Respond to what the user said in a creative, helpful, and brief way.",
+            ),
+        )
+
+        context = LLMContext()
+        user_aggregator, assistant_aggregator = LLMContextAggregatorPair(
+            context,
+            user_params=LLMUserAggregatorParams(vad_analyzer=SileroVADAnalyzer()),
+        )
+
+        pipeline = Pipeline(
+            [
+                transport.input(),  # Transport user input
+                stt,
+                user_aggregator,  # User responses
+                llm,  # LLM
+                tts,  # TTS
+                transport.output(),  # Transport bot output
+                assistant_aggregator,  # Assistant spoken responses
+            ]
+        )
+
+        task = PipelineTask(
+            pipeline,
+            params=PipelineParams(
+                enable_metrics=True,
+                enable_usage_metrics=True,
+                audio_out_sample_rate=8000,
+            ),
+            idle_timeout_secs=runner_args.pipeline_idle_timeout_secs,
+        )
+
+        @transport.event_handler("on_client_connected")
+        async def on_client_connected(transport, client):
+            logger.info(f"Client connected")
+            # Kick off the conversation.
+            context.add_message(
+                {"role": "user", "content": "Please introduce yourself to the user."}
+            )
+            await task.queue_frames([LLMRunFrame()])
+
+        @transport.event_handler("on_client_disconnected")
+        async def on_client_disconnected(transport, client):
+            logger.info(f"Client disconnected")
+            await task.cancel()
+
+        runner = PipelineRunner(handle_sigint=runner_args.handle_sigint)
+
+        await runner.run(task)
+
+
+async def bot(runner_args: RunnerArguments):
+    """Main bot entry point compatible with Pipecat Cloud."""
+    transport = await create_transport(runner_args, transport_params)
+    await run_bot(transport, runner_args)
+
+
+if __name__ == "__main__":
+    from pipecat.runner.run import main
+
+    main()

examples/foundational/14g-function-calling-grok.py

@@ -7,6 +7,7 @@
 
 import os
 
+import aiohttp
 from dotenv import load_dotenv
 from loguru import logger
 
@@ -24,10 +25,10 @@ from pipecat.processors.aggregators.llm_response_universal import (
 )
 from pipecat.runner.types import RunnerArguments
 from pipecat.runner.utils import create_transport
-from pipecat.services.cartesia.tts import CartesiaTTSService
 from pipecat.services.deepgram.stt import DeepgramSTTService
 from pipecat.services.grok.llm import GrokLLMService
 from pipecat.services.llm_service import FunctionCallParams
+from pipecat.services.xai.tts import XAIHttpTTSService
 from pipecat.transports.base_transport import BaseTransport, TransportParams
 from pipecat.transports.daily.transport import DailyParams
 from pipecat.transports.websocket.fastapi import FastAPIWebsocketParams
@@ -60,83 +61,88 @@ transport_params = {
 async def run_bot(transport: BaseTransport, runner_args: RunnerArguments):
     logger.info(f"Starting bot")
 
-    stt = DeepgramSTTService(api_key=os.getenv("DEEPGRAM_API_KEY"))
+    async with aiohttp.ClientSession() as session:
+        stt = DeepgramSTTService(api_key=os.getenv("DEEPGRAM_API_KEY"))
 
-    tts = CartesiaTTSService(
+        tts = XAIHttpTTSService(
-        api_key=os.getenv("CARTESIA_API_KEY"),
+            api_key=os.getenv("GROK_API_KEY"),
-        settings=CartesiaTTSService.Settings(
+            aiohttp_session=session,
-            voice="71a7ad14-091c-4e8e-a314-022ece01c121",  # British Reading Lady
+            settings=XAIHttpTTSService.Settings(
-        ),
+                voice="eve",
-    )
+            ),
+        )
 
-    llm = GrokLLMService(
+        llm = GrokLLMService(
-        api_key=os.getenv("GROK_API_KEY"),
+            api_key=os.getenv("GROK_API_KEY"),
-        settings=GrokLLMService.Settings(
+            settings=GrokLLMService.Settings(
-            system_instruction="You are a helpful assistant in a voice conversation. Your responses will be spoken aloud, so avoid emojis, bullet points, or other formatting that can't be spoken. Respond to what the user said in a creative, helpful, and brief way.",
+                system_instruction="You are a helpful assistant in a voice conversation. Your responses will be spoken aloud, so avoid emojis, bullet points, or other formatting that can't be spoken. Respond to what the user said in a creative, helpful, and brief way.",
-        ),
+            ),
-    )
+        )
-    # You can also register a function_name of None to get all functions
+        # You can also register a function_name of None to get all functions
-    # sent to the same callback with an additional function_name parameter.
+        # sent to the same callback with an additional function_name parameter.
-    llm.register_function("get_current_weather", fetch_weather_from_api)
+        llm.register_function("get_current_weather", fetch_weather_from_api)
 
-    weather_function = FunctionSchema(
+        weather_function = FunctionSchema(
-        name="get_current_weather",
+            name="get_current_weather",
-        description="Get the current weather",
+            description="Get the current weather",
-        properties={
+            properties={
-            "location": {
+                "location": {
-                "type": "string",
+                    "type": "string",
-                "description": "The city and state, e.g. San Francisco, CA",
+                    "description": "The city and state, e.g. San Francisco, CA",
+                },
+                "format": {
+                    "type": "string",
+                    "enum": ["celsius", "fahrenheit"],
+                    "description": "The temperature unit to use. Infer this from the user's location.",
+                },
             },
-            "format": {
+            required=["location", "format"],
-                "type": "string",
+        )
-                "enum": ["celsius", "fahrenheit"],
+        tools = ToolsSchema(standard_tools=[weather_function])
-                "description": "The temperature unit to use. Infer this from the user's location.",
+        context = LLMContext(tools=tools)
-            },
+        user_aggregator, assistant_aggregator = LLMContextAggregatorPair(
-        },
+            context,
-        required=["location", "format"],
+            user_params=LLMUserAggregatorParams(vad_analyzer=SileroVADAnalyzer()),
-    )
+        )
-    tools = ToolsSchema(standard_tools=[weather_function])
-    context = LLMContext(tools=tools)
-    user_aggregator, assistant_aggregator = LLMContextAggregatorPair(
-        context,
-        user_params=LLMUserAggregatorParams(vad_analyzer=SileroVADAnalyzer()),
-    )
 
-    pipeline = Pipeline(
+        pipeline = Pipeline(
-        [
+            [
-            transport.input(),
+                transport.input(),
-            stt,
+                stt,
-            user_aggregator,
+                user_aggregator,
-            llm,
+                llm,
-            tts,
+                tts,
-            transport.output(),
+                transport.output(),
-            assistant_aggregator,
+                assistant_aggregator,
-        ]
+            ]
-    )
+        )
 
-    task = PipelineTask(
+        task = PipelineTask(
-        pipeline,
+            pipeline,
-        params=PipelineParams(
+            params=PipelineParams(
-            enable_metrics=True,
+                enable_metrics=True,
-            enable_usage_metrics=True,
+                enable_usage_metrics=True,
-        ),
+            ),
-        idle_timeout_secs=runner_args.pipeline_idle_timeout_secs,
+            idle_timeout_secs=runner_args.pipeline_idle_timeout_secs,
-    )
+        )
 
-    @transport.event_handler("on_client_connected")
+        @transport.event_handler("on_client_connected")
-    async def on_client_connected(transport, client):
+        async def on_client_connected(transport, client):
-        logger.info(f"Client connected")
+            logger.info(f"Client connected")
-        # Kick off the conversation.
+            # Kick off the conversation.
-        await task.queue_frames([LLMRunFrame()])
+            context.add_message(
+                {"role": "user", "content": "Please introduce yourself to the user."}
+            )
+            await task.queue_frames([LLMRunFrame()])
 
-    @transport.event_handler("on_client_disconnected")
+        @transport.event_handler("on_client_disconnected")
-    async def on_client_disconnected(transport, client):
+        async def on_client_disconnected(transport, client):
-        logger.info(f"Client disconnected")
+            logger.info(f"Client disconnected")
-        await task.cancel()
+            await task.cancel()
 
-    runner = PipelineRunner(handle_sigint=runner_args.handle_sigint)
+        runner = PipelineRunner(handle_sigint=runner_args.handle_sigint)
 
-    await runner.run(task)
+        await runner.run(task)
 
 
 async def bot(runner_args: RunnerArguments):

src/pipecat/services/xai/tts.py

@@ -15,23 +15,60 @@ from typing import AsyncGenerator, Optional
 
 import aiohttp
 from loguru import logger
-from pydantic import BaseModel
 
 from pipecat.frames.frames import ErrorFrame, Frame, TTSAudioRawFrame
 from pipecat.services.settings import TTSSettings
 from pipecat.services.tts_service import TTSService
-from pipecat.transcriptions.language import Language
+from pipecat.transcriptions.language import Language, resolve_language
 from pipecat.utils.tracing.service_decorators import traced_tts
 
 
+def language_to_xai_language(language: Language) -> Optional[str]:
+    """Convert a Language enum to xAI language code.
+
+    Args:
+        language: The Language enum value to convert.
+
+    Returns:
+        The corresponding xAI language code, or None if not supported.
+    """
+    LANGUAGE_MAP = {
+        Language.AR: "ar-EG",
+        Language.AR_EG: "ar-EG",
+        Language.AR_SA: "ar-SA",
+        Language.AR_AE: "ar-AE",
+        Language.BN: "bn",
+        Language.DE: "de",
+        Language.EN: "en",
+        Language.ES: "es-ES",
+        Language.ES_ES: "es-ES",
+        Language.ES_MX: "es-MX",
+        Language.FR: "fr",
+        Language.HI: "hi",
+        Language.ID: "id",
+        Language.IT: "it",
+        Language.JA: "ja",
+        Language.KO: "ko",
+        Language.PT: "pt-PT",
+        Language.PT_BR: "pt-BR",
+        Language.PT_PT: "pt-PT",
+        Language.RU: "ru",
+        Language.TR: "tr",
+        Language.VI: "vi",
+        Language.ZH: "zh",
+    }
+
+    return resolve_language(language, LANGUAGE_MAP, use_base_code=True)
+
+
 @dataclass
 class XAITTSSettings(TTSSettings):
-    """Settings for XAITTSService."""
+    """Settings for XAIHttpTTSService."""
 
     pass
 
 
-class XAITTSService(TTSService):
+class XAIHttpTTSService(TTSService):
     """xAI HTTP text-to-speech service.
 
     The service requests raw PCM audio so emitted ``TTSAudioRawFrame`` objects
@@ -41,31 +78,14 @@ class XAITTSService(TTSService):
     Settings = XAITTSSettings
     _settings: Settings
 
-    XAI_DEFAULT_SAMPLE_RATE = 24000
-    XAI_PCM_CODEC = "pcm"
-
-    class InputParams(BaseModel):
-        """Input parameters for xAI TTS configuration.
-
-        .. deprecated:: 0.0.105
-            Use ``settings=XAITTSService.Settings(...)`` instead.
-
-        Parameters:
-            language: Language for speech synthesis.
-        """
-
-        language: Optional[Language] = None
-
     def __init__(
         self,
         *,
         api_key: str,
         base_url: str = "https://api.x.ai/v1/tts",
-        voice: Optional[str] = None,
-        language: Optional[str | Language] = None,
         sample_rate: Optional[int] = None,
+        encoding: Optional[str] = "pcm",
         aiohttp_session: Optional[aiohttp.ClientSession] = None,
-        params: Optional[InputParams] = None,
         settings: Optional[Settings] = None,
         **kwargs,
     ):
@@ -74,54 +94,25 @@ class XAITTSService(TTSService):
         Args:
             api_key: xAI API key for authentication.
             base_url: xAI TTS endpoint. Defaults to ``https://api.x.ai/v1/tts``.
-            voice: Voice identifier. Defaults to ``"eve"``.
+            sample_rate: Audio sample rate. If None, uses default.
-
+            encoding: Output encoding format. Defaults to "pcm".
-                .. deprecated:: 0.0.105
-                    Use ``settings=XAITTSService.Settings(voice=...)`` instead.
-
-            language: BCP-47 or base language code (for example ``"en"`` or ``"pt-BR"``).
-                Defaults to ``"en"``.
-
-                .. deprecated:: 0.0.105
-                    Use ``settings=XAITTSService.Settings(language=...)`` instead.
-
-            sample_rate: Output sample rate for PCM audio. Defaults to 24000 Hz.
             aiohttp_session: Optional shared aiohttp session.
-            params: Deprecated input parameters object.
+            settings: Runtime-updatable settings.
-            settings: Runtime-updatable settings. When provided alongside deprecated
-                parameters, ``settings`` values take precedence.
             **kwargs: Additional keyword arguments passed to ``TTSService``.
         """
         default_settings = self.Settings(
             model=None,
             voice="eve",
-            language="en",
+            language=Language.EN,
         )
 
-        if voice is not None:
-            self._warn_init_param_moved_to_settings("voice", "voice")
-            default_settings.voice = voice
-        if language is not None:
-            self._warn_init_param_moved_to_settings("language", "language")
-            default_settings.language = (
-                self.language_to_service_language(language)
-                if isinstance(language, Language)
-                else language
-            )
-
-        if params is not None:
-            self._warn_init_param_moved_to_settings("params")
-            if not settings and params.language is not None:
-                default_settings.language = self.language_to_service_language(params.language)
-
         if settings is not None:
             default_settings.apply_update(settings)
 
         super().__init__(
-            pause_frame_processing=True,
+            sample_rate=sample_rate,
             push_start_frame=True,
             push_stop_frames=True,
-            sample_rate=sample_rate or self.XAI_DEFAULT_SAMPLE_RATE,
             settings=default_settings,
             **kwargs,
         )
@@ -130,14 +121,22 @@ class XAITTSService(TTSService):
         self._base_url = base_url
         self._session = aiohttp_session
         self._session_owner = aiohttp_session is None
+        self._encoding = encoding
 
     def can_generate_metrics(self) -> bool:
         """Check if this service can generate processing metrics."""
         return True
 
     def language_to_service_language(self, language: Language) -> Optional[str]:
-        """Convert a Language enum to xAI's language format."""
+        """Convert a Language enum to xAI language format.
-        return str(language)
+
+        Args:
+            language: The language to convert.
+
+        Returns:
+            The xAI-specific language code, or None if not supported.
+        """
+        return language_to_xai_language(language)
 
     async def start(self, frame):
         """Start the xAI TTS service."""
@@ -175,7 +174,7 @@ class XAITTSService(TTSService):
             "text": text,
             "voice_id": self._settings.voice,
             "output_format": {
-                "codec": self.XAI_PCM_CODEC,
+                "codec": self._encoding,
                 "sample_rate": self.sample_rate,
             },
         }
@@ -189,12 +188,11 @@ class XAITTSService(TTSService):
 
         measuring_ttfb = True
         try:
-            async with self._session.post(self._base_url, json=payload, headers=headers) as response:
+            async with self._session.post(
+                self._base_url, json=payload, headers=headers
+            ) as response:
                 if response.status != 200:
                     error = await response.text(errors="ignore")
-                    logger.error(
-                        f"{self} error getting audio (status: {response.status}, error: {error})"
-                    )
                     yield ErrorFrame(
                         error=f"Error getting audio (status: {response.status}, error: {error})"
                     )
@@ -208,6 +206,11 @@ class XAITTSService(TTSService):
                     if measuring_ttfb:
                         await self.stop_ttfb_metrics()
                         measuring_ttfb = False
-                    yield TTSAudioRawFrame(chunk, self.sample_rate, 1, context_id=context_id)
+                    yield TTSAudioRawFrame(
+                        chunk,
+                        self.sample_rate,
+                        1,
+                        context_id=context_id,
+                    )
         except Exception as e:
             yield ErrorFrame(error=f"Unknown error occurred: {e}")

tests/test_xai_tts.py

@@ -21,7 +21,7 @@ from pipecat.frames.frames import (
     TTSStoppedFrame,
     TTSTextFrame,
 )
-from pipecat.services.xai.tts import XAITTSService
+from pipecat.services.xai.tts import XAIHttpTTSService
 from pipecat.tests.utils import run_test
 
 
@@ -52,7 +52,7 @@ async def test_run_xai_tts_success(aiohttp_client):
     base_url = str(client.make_url("/v1/tts"))
 
     async with aiohttp.ClientSession() as session:
-        tts_service = XAITTSService(
+        tts_service = XAIHttpTTSService(
             api_key="test-key",
             base_url=base_url,
             aiohttp_session=session,

uv.lock

@@ -4966,7 +4966,11 @@ requires-dist = [
     { name = "wait-for2", marker = "python_full_version < '3.12'", specifier = ">=0.4.1,<1" },
     { name = "websockets", marker = "extra == 'websockets-base'", specifier = ">=13.1,<16.0" },
 ]
+<<<<<<< HEAD
 provides-extras = ["aic", "anthropic", "assemblyai", "asyncai", "aws", "aws-nova-sonic", "azure", "cartesia", "camb", "cerebras", "daily", "deepgram", "deepseek", "elevenlabs", "fal", "fireworks", "fish", "gladia", "google", "gradium", "grok", "groq", "gstreamer", "heygen", "hume", "inworld", "koala", "kokoro", "krisp", "langchain", "lemonslice", "livekit", "lmnt", "local", "local-smart-turn", "mcp", "mem0", "mistral", "mlx-whisper", "moondream", "neuphonic", "noisereduce", "novita", "nvidia", "openai", "rnnoise", "openpipe", "openrouter", "perplexity", "piper", "qwen", "remote-smart-turn", "resembleai", "rime", "riva", "runner", "sagemaker", "sambanova", "sarvam", "smallest", "sentry", "silero", "simli", "soniox", "soundfile", "speechmatics", "strands", "tavus", "together", "tracing", "ultravox", "webrtc", "websocket", "websockets-base", "whisper"]
+=======
+provides-extras = ["aic", "anthropic", "assemblyai", "asyncai", "aws", "aws-nova-sonic", "azure", "cartesia", "camb", "cerebras", "daily", "deepgram", "deepseek", "elevenlabs", "fal", "fireworks", "fish", "gladia", "google", "gradium", "grok", "groq", "gstreamer", "heygen", "hume", "inworld", "koala", "kokoro", "krisp", "langchain", "lemonslice", "livekit", "lmnt", "local", "local-smart-turn", "mcp", "mem0", "mistral", "mlx-whisper", "moondream", "neuphonic", "noisereduce", "novita", "nvidia", "openai", "rnnoise", "openpipe", "openrouter", "perplexity", "piper", "qwen", "remote-smart-turn", "resembleai", "rime", "riva", "runner", "sagemaker", "sambanova", "sarvam", "sentry", "silero", "simli", "soniox", "soundfile", "speechmatics", "strands", "tavus", "together", "tracing", "ultravox", "webrtc", "websocket", "websockets-base", "whisper", "xai"]
+>>>>>>> 43f25faca (Add xAI HTTP TTS service)
 
 [package.metadata.requires-dev]
 dev = [