Reject unsupported LLM providers

.env.example

@@ -1,7 +1,7 @@
 # Enable or disable running the MCP server
 RUN_MCP_SERVER=true
 
-# LLM provider (anthropic, openai, mistral, gemini, ollama)
+# LLM provider (anthropic, openai)
 LM_PROVIDER=anthropic
 
 # Default model name for the LLM

README.md

@@ -15,7 +15,7 @@ This repository bundles the OCL Model Context Protocol (MCP) server together wit
 
 - Python 3.10+ (3.12 is used inside the Docker image) with access to the filesystem where the repo lives.
 - An optional OCL API token when you need access to private or organization-owned repositories.
-- Optional LLM provider credentials (for example, Anthropic) if you plan to use the UI’s chat experience.
+- Optional LLM provider credentials for Anthropic or OpenAI if you plan to use the UI’s chat experience.
 
 ## Configuration
 
@@ -27,7 +27,7 @@ Important variables:
 |---|---|
 | `OCL_TOKEN` | OCL API token (40 characters) for authenticated concept/mapping requests. |
 | `OCL_URL` | Override for the OCL base URL; `chat` defaults to production but allows `staging`, `local`, or any custom URL. |
-| `LM_PROVIDER` | Sets a default provider in the UI (defaults to `anthropic`). |
+| `LM_PROVIDER` | Sets a default provider in the UI. Supported values are `anthropic` and `openai` (defaults to `anthropic`). |
 | `LM_MODEL` | Preferred model name for the chat session. |
 | `LM_TOKEN` | API key for the chosen LLM provider (passed straight to the UI). |
 | `UI_HOST` / `UI_PORT` | Host and port for the FastAPI app (default `0.0.0.0:8002`). |
@@ -82,4 +82,3 @@ Compose loads `.env`, exposes port `8002`, and uses the healthcheck in `docker-c
 
 - See `mcp-server/README.md` for detailed MCP server usage, tooling, and available MCP endpoints.
 - `mcp-server/docs/` contains auxiliary guides (Claude configuration, examples, etc.).
-*** End Patch

mcp-client/routes/frontend.py

@@ -1,14 +1,15 @@
 import os
 import json
 from typing import List, Optional, Dict, Any
-from fastapi import APIRouter, Request, Body
+from fastapi import APIRouter, Body, HTTPException, Request
 from fastapi.responses import RedirectResponse, JSONResponse
 from langchain_anthropic import ChatAnthropic
 from langchain_openai import ChatOpenAI
 from langchain_core.tools import tool, StructuredTool
 from langchain_core.messages import HumanMessage, SystemMessage, AIMessage, ToolMessage
 
 from mcp import types as mcp_types
+from routes.providers import normalize_provider
 from web_config import templates
 from ocl_mcp.server import OCLMCPServer
 from ocl_mcp.tools import (
@@ -235,13 +236,16 @@ async def chat_message(request: Request, payload: dict = Body(...)):
 
     # Initialize LLM
     config_payload = payload.get("config", {})
-    provider = config_payload.get("provider") or os.getenv("LM_PROVIDER", "anthropic")
+    try:
+        provider = normalize_provider(config_payload.get("provider") or os.getenv("LM_PROVIDER"))
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc)) from exc
     model_name = config_payload.get("model") or os.getenv("LM_MODEL")
     api_key = config_payload.get("api_key") or os.getenv("LM_TOKEN")
 
     if provider == "openai":
         llm = ChatOpenAI(model=model_name or "gpt-4o", api_key=api_key)
-    else:
+    elif provider == "anthropic":
         llm = ChatAnthropic(model=model_name or "claude-3-5-sonnet-20241022", api_key=api_key)
 
     # Bind tools

mcp-client/routes/providers.py

@@ -0,0 +1,10 @@
+DEFAULT_PROVIDER = "anthropic"
+SUPPORTED_LM_PROVIDERS = ("anthropic", "openai")
+
+
+def normalize_provider(provider):
+    provider = (provider or DEFAULT_PROVIDER).strip().lower() or DEFAULT_PROVIDER
+    if provider not in SUPPORTED_LM_PROVIDERS:
+        supported = ", ".join(SUPPORTED_LM_PROVIDERS)
+        raise ValueError(f"Unsupported LLM provider '{provider}'. Supported providers: {supported}.")
+    return provider

mcp-client/templates/chat.html

@@ -108,9 +108,6 @@ <h2>Session configuration</h2>
           <select id="provider" name="provider" required>
             <option value="openai">OpenAI</option>
             <option value="anthropic">Anthropic</option>
-            <option value="mistral">Mistral</option>
-            <option value="gemini">Google Gemini</option>
-            <option value="ollama">Ollama</option>
           </select>
         </div>
         <div class="form-field">

tests/test_provider_config.py

@@ -0,0 +1,42 @@
+import importlib.util
+import unittest
+from pathlib import Path
+
+
+PROVIDER_MODULE_PATH = (
+    Path(__file__).resolve().parents[1] / "mcp-client" / "routes" / "providers.py"
+)
+
+
+def load_provider_module():
+    spec = importlib.util.spec_from_file_location("provider_config", PROVIDER_MODULE_PATH)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+class ProviderConfigTest(unittest.TestCase):
+    def test_normalize_provider_defaults_to_anthropic(self):
+        providers = load_provider_module()
+
+        self.assertEqual(providers.normalize_provider(None), "anthropic")
+        self.assertEqual(providers.normalize_provider(""), "anthropic")
+
+    def test_normalize_provider_accepts_supported_providers_case_insensitively(self):
+        providers = load_provider_module()
+
+        self.assertEqual(providers.normalize_provider(" OpenAI "), "openai")
+        self.assertEqual(providers.normalize_provider("ANTHROPIC"), "anthropic")
+
+    def test_normalize_provider_rejects_unsupported_providers(self):
+        providers = load_provider_module()
+
+        with self.assertRaises(ValueError) as context:
+            providers.normalize_provider("gemini")
+
+        self.assertIn("Unsupported LLM provider 'gemini'", str(context.exception))
+        self.assertIn("anthropic, openai", str(context.exception))
+
+
+if __name__ == "__main__":
+    unittest.main()