add support for openrouter.

Signed-off-by: sahil suman <sahilsuman933@gmail.com>

dot-env.template

@@ -60,3 +60,6 @@ SIMLI_FACE_ID=...
 
 # Krisp
 KRISP_MODEL_PATH=...
+
+# OpenRouter
+OPENROUTER_API_KEY=...

examples/foundational/07u-interruptible-openrouter.py

@@ -0,0 +1,96 @@
+import asyncio
+import os
+import sys
+
+import aiohttp
+from dotenv import load_dotenv
+from loguru import logger
+from runner import configure
+
+from pipecat.frames.frames import LLMMessagesFrame
+from pipecat.pipeline.pipeline import Pipeline
+from pipecat.pipeline.runner import PipelineRunner
+from pipecat.pipeline.task import PipelineTask, PipelineParams
+from pipecat.services.azure import AzureTTSService
+from pipecat.services.openrouter import OpenRouterLLMService
+from pipecat.services.openai import OpenAILLMContext
+from pipecat.transports.services.daily import DailyParams, DailyTransport
+from pipecat.audio.vad.silero import SileroVADAnalyzer
+
+load_dotenv(override=True)
+
+logger.remove(0)
+logger.add(sys.stderr, level="DEBUG")
+
+
+async def main():
+    async with aiohttp.ClientSession() as session:
+        (room_url, token) = await configure(session)
+
+        transport = DailyTransport(
+            room_url,
+            token,
+            "Chatbot",
+            DailyParams(
+                audio_out_enabled=True,
+                transcription_enabled=True,
+                vad_enabled=True,
+                vad_analyzer=SileroVADAnalyzer(),
+                vad_audio_passthrough=True,
+            ),
+        )
+
+        tts = AzureTTSService(
+            api_key=os.getenv("AZURE_API_KEY"),
+            region="eastus",
+            voice="en-US-JennyNeural",
+            params=AzureTTSService.InputParams(
+                language="en-US",
+                rate="1.1",
+                style="chat",
+            ),
+        )
+
+        llm = OpenRouterLLMService(
+            api_key=os.getenv("OPENROUTER_API_KEY"), model="microsoft/phi-4"
+        )
+        messages = [
+            {
+                "role": "system",
+                "content": "You are a helpful LLM in a WebRTC call. Your goal is to demonstrate your capabilities in a succinct way. Your output will be converted to audio so don't include special characters in your answers. Respond to what the user said in a creative, helpful, and brief way.",
+            }
+        ]
+        context = OpenAILLMContext(messages=messages)
+        context_aggregator = llm.create_context_aggregator(context)
+
+        pipeline = Pipeline(
+            [
+                transport.input(),
+                context_aggregator.user(),
+                llm,
+                tts,
+                transport.output(),
+                context_aggregator.assistant(),
+            ]
+        )
+
+        task = PipelineTask(
+            pipeline,
+            PipelineParams(allow_interruptions=True),
+        )
+
+        @transport.event_handler("on_first_participant_joined")
+        async def on_first_participant_joined(transport, participant):
+            await transport.capture_participant_transcription(participant["id"])
+            messages.append(
+                {"role": "system", "content": "Please introduce yourself to the user."}
+            )
+            await task.queue_frames([LLMMessagesFrame(messages)])
+
+        runner = PipelineRunner()
+
+        await runner.run(task)
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

src/pipecat/services/openrouter.py

@@ -0,0 +1,62 @@
+#
+# Copyright (c) 2025, Daily
+#
+# SPDX-License-Identifier: BSD 2-Clause License
+#
+
+from typing import Dict, List
+
+from loguru import logger
+
+from pipecat.processors.aggregators.openai_llm_context import OpenAILLMContext
+from pipecat.services.openai import OpenAILLMService
+
+try:
+    from openai import AsyncStream, OpenAI
+    from openai.types.chat import ChatCompletionChunk, ChatCompletionMessageParam
+except ModuleNotFoundError as e:
+    logger.error(f"Exception: {e}")
+    logger.error(
+        "In order to use OpenRouter, you need to `pip install pipecat-ai[openai]`. Also, set `OPENROUTER_API_KEY` environment variable."
+    )
+    raise Exception(f"Missing module: {e}")
+
+
+class OpenRouterLLMService(OpenAILLMService):
+    def __init__(
+        self,
+        *,
+        api_key: str | None = None,
+        model: str = "openai/gpt-4o-latest",
+        base_url: str = "https://openrouter.ai/api/v1",
+        **kwargs,
+    ):
+        super().__init__(
+            api_key=api_key,
+            base_url=base_url,
+            model=model,
+            **kwargs,
+        )
+
+    def create_client(self, api_key=None, base_url=None, **kwargs):
+        logger.debug(f"Creating OpenRouter client with api {base_url}")
+        return super().create_client(api_key, base_url, **kwargs)
+
+    async def get_chat_completions(
+        self, context: OpenAILLMContext, messages: List[ChatCompletionMessageParam]
+    ) -> AsyncStream[ChatCompletionChunk]:
+        params = {
+            "model": self.model_name,
+            "stream": True,
+            "messages": messages,
+            "temperature": self._settings["temperature"],
+            "top_p": self._settings["top_p"],
+            "max_tokens": self._settings["max_tokens"],
+            "frequency_penalty": self._settings["frequency_penalty"],
+            "presence_penalty": self._settings["presence_penalty"],
+        }
+
+        params.update(self._settings["extra"])
+
+        chunks = await self._client.chat.completions.create(**params)
+        return chunks