feat: add Cohere plugin for LiveKit Agents

livekit-plugins/livekit-plugins-openai/livekit/plugins/openai/__init__.py

@@ -17,7 +17,7 @@
 Support for OpenAI Realtime API, LLM, TTS, and STT APIs.
 
 Also includes support for a large number of OpenAI-compatible APIs including Azure OpenAI, Cerebras,
-Fireworks, Perplexity, Telnyx, xAI, Ollama, DeepSeek, OpenRouter, and OVHcloud AI Endpoints.
+Fireworks, Perplexity, Telnyx, xAI, Ollama, DeepSeek, OpenRouter, Cohere, and OVHcloud AI Endpoints.
 
 See https://docs.livekit.io/agents/integrations/openai/ and
 https://docs.livekit.io/agents/integrations/llm/ for more information.
@@ -27,6 +27,7 @@
 from .embeddings import EmbeddingData, create_embeddings
 from .llm import LLM, LLMStream
 from .models import (
+    CohereChatModels,
     OpenRouterProviderPreferences,
     OpenRouterWebPlugin,
     STTModels,
@@ -42,6 +43,7 @@
     "TTS",
     "LLM",
     "LLMStream",
+    "CohereChatModels",
     "OpenRouterProviderPreferences",
     "OpenRouterWebPlugin",
     "STTModels",

livekit-plugins/livekit-plugins-openai/livekit/plugins/openai/llm.py

@@ -26,6 +26,7 @@
 from livekit.agents.inference.llm import LLMStream as _LLMStream
 from livekit.agents.llm import (
     ChatContext,
+    ChatMessage,
     FunctionTool,
     ProviderTool,
     RawFunctionTool,
@@ -45,6 +46,7 @@
 from .models import (
     CerebrasChatModels,
     ChatModels,
+    CohereChatModels,
     CometAPIChatModels,
     DeepSeekChatModels,
     NebiusChatModels,
@@ -447,6 +449,44 @@ def with_openrouter(
             timeout=timeout,
         )
 
+    @staticmethod
+    def with_cohere(
+        *,
+        model: str | CohereChatModels = "command-r-08-2024",
+        api_key: str | None = None,
+        base_url: str = "https://api.cohere.ai/compatibility/v1",
+        client: openai.AsyncClient | None = None,
+        temperature: NotGivenOr[float] = NOT_GIVEN,
+        tool_choice: NotGivenOr[ToolChoice] = NOT_GIVEN,
+        top_p: NotGivenOr[float] = NOT_GIVEN,
+        max_completion_tokens: NotGivenOr[int] = NOT_GIVEN,
+        timeout: httpx.Timeout | None = None,
+    ) -> LLM:
+        """
+        Create a new instance of Cohere LLM using OpenAI-compatible API.
+
+        ``api_key`` must be set to your Cohere API key, either using the argument or by setting
+        the ``COHERE_API_KEY`` environment variable.
+        """
+        api_key = api_key or os.environ.get("COHERE_API_KEY")
+        if api_key is None:
+            raise ValueError(
+                "Cohere API key is required, either as argument or set COHERE_API_KEY environment variable"
+            )
+
+        return LLM(
+            model=model,
+            api_key=api_key,
+            client=client,
+            base_url=base_url,
+            temperature=temperature,
+            tool_choice=tool_choice,
+            top_p=top_p,
+            max_completion_tokens=max_completion_tokens,
+            timeout=timeout,
+            _strict_tool_schema=False,
+        )
+
     @staticmethod
     def with_deepseek(
         *,
@@ -961,6 +1001,16 @@ def chat(
         if is_given(response_format):
             extra["response_format"] = llm_utils.to_openai_response_format(response_format)  # type: ignore
 
+        # Cohere requires at least one user message to generate a response
+        if "api.cohere.ai" in str(self._client.base_url):
+            has_user_message = any(
+                isinstance(item, ChatMessage) and item.role == "user" for item in chat_ctx.items
+            )
+
+            if not has_user_message:
+                placeholder_msg = ChatMessage(role="user", content=["."])
+                chat_ctx.items.append(placeholder_msg)
+
         return LLMStream(
             self,
             model=self._opts.model,

livekit-plugins/livekit-plugins-openai/livekit/plugins/openai/models.py

@@ -290,6 +290,16 @@
     "grok-2-1212",
 ]
 
+CohereChatModels = Literal[
+    "command-a-03-2025",
+    "command-r7b-12-2024",
+    "command-a-translate-08-2025",
+    "command-a-reasoning-08-2025",
+    "command-a-vision-07-2025",
+    "command-r-08-2024",
+    "command-r-plus-08-2024",
+]
+
 
 def _supports_reasoning_effort(model: Union[ChatModels, str]) -> bool:
     return model in [