feat: add /health endpoint and switch to Streamable HTTP transport

- Switch from legacy SSE transport (sse_app) to Streamable HTTP (http_app)
  - Fixes 405 Method Not Allowed for MCP clients like Gemini CLI
  - MCP endpoint now at /mcp (POST) instead of /sse (GET)

- Add /health endpoint that bypasses MCP_ALLOWED_HOSTS validation
  - Returns {"status": "ok"} (200) or {"status": "degraded"} (503)
  - Enables Docker health checks without exposing to external hosts

- Add curl to Docker image for health checks
- Add healthcheck config to docker-compose files
- Add test-health and test-mcp Makefile targets
- Update documentation

Dockerfile

@@ -15,6 +15,10 @@ RUN uv pip install --system .
 # Stage 2: Final image
 FROM python:3.11-slim-bullseye
 
+# Install curl for health checks
+RUN apt-get update && apt-get install -y --no-install-recommends curl \
+    && rm -rf /var/lib/apt/lists/*
+
 WORKDIR /app
 
 # Copy installed dependencies from builder

IMPLEMENTATION.md

@@ -8,7 +8,7 @@ Technical documentation for the Komodo MCP Server.
 ┌─────────────────────────────────────────────────────────┐
 │                    MCP Client (AI Agent)                │
 └─────────────────────────┬───────────────────────────────┘
-                          │ SSE
+                          │ HTTP (POST /mcp)
                           ▼
 ┌─────────────────────────────────────────────────────────┐
 │              Docker Container (komodo-mcp)              │

Makefile

@@ -1,4 +1,4 @@
-.PHONY: build dev logs stop test-sse clean rebuild
+.PHONY: build dev logs stop test-mcp test-health clean rebuild
 
 # Build the Docker image locally
 build:
@@ -18,15 +18,22 @@ logs:
 stop:
 	docker compose -f docker-compose.dev.yml down
 
-# Test SSE endpoint (5 second timeout)
-test-sse:
-	@echo "Testing SSE endpoint (5s timeout)..."
-	@curl -N --max-time 5 http://localhost:8001/sse 2>/dev/null || echo "\n[Timeout - this is expected for SSE]"
+# Test MCP endpoint (POST to /mcp)
+test-mcp:
+	@echo "Testing MCP endpoint..."
+	@curl -s -X POST http://localhost:8001/mcp \
+		-H "Content-Type: application/json" \
+		-d '{"jsonrpc": "2.0", "method": "initialize", "params": {"protocolVersion": "2024-11-05", "capabilities": {}, "clientInfo": {"name": "test", "version": "1.0"}}, "id": 1}' | head -200
 
 # Test root endpoint
 test-root:
 	@curl -s http://localhost:8001/ | head -20
 
+# Test health endpoint (bypasses MCP_ALLOWED_HOSTS)
+test-health:
+	@echo "Testing health endpoint..."
+	@curl -s http://localhost:8001/health
+
 # Full rebuild (no cache)
 rebuild:
 	docker compose -f docker-compose.dev.yml build --no-cache

README.md

@@ -45,14 +45,22 @@ services:
       - KOMODO_URL=https://komodo.example.com
       - KOMODO_API_KEY=your-key
       - KOMODO_API_SECRET=your-secret
-      - MCP_ALLOWED_HOSTS=komodo-mcp.example.io,localhost:*
+      - MCP_ALLOWED_HOSTS=komodo-mcp.example.io
     ports:
       - "8000:8000"
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
 ```
 
-### Connect MCP Client
+### Endpoints
 
-SSE endpoint: `https://your-host/sse`
+| Endpoint | Method | Description |
+|----------|--------|-------------|
+| `/mcp` | POST | MCP protocol endpoint |
+| `/health` | GET | Health check (bypasses `MCP_ALLOWED_HOSTS`) |
 
 ## Local Development
 
@@ -67,12 +75,12 @@ make dev
 
 # Test
 make logs
-make test-sse
+make test-mcp
 make stop
 ```
 
 ## Tech Stack
 
 - Python 3.11+ / FastMCP / httpx
-- SSE transport / uvicorn
+- Streamable HTTP transport / uvicorn
 - Docker with multi-stage build

docker-compose.dev.yml

@@ -6,4 +6,10 @@ services:
       - .env
     ports:
       - "8001:8000"
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 5s
     restart: unless-stopped

docker-compose.yml

@@ -9,4 +9,10 @@ services:
       - MCP_ALLOWED_HOSTS=komodo-mcp.example.io,localhost:*,127.0.0.1:*
     ports:
       - "8000:8000"
+    healthcheck:
+      test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 5s
     restart: unless-stopped

server.py

@@ -3,6 +3,9 @@ import logging
 import httpx
 from mcp.server.fastmcp import FastMCP
 from mcp.server.transport_security import TransportSecuritySettings
+from starlette.applications import Starlette
+from starlette.responses import JSONResponse
+from starlette.routing import Route, Mount
 from dotenv import load_dotenv
 
 # Load environment variables
@@ -225,6 +228,36 @@ def komodo_api_call(
     return method(request_type, params or {})
 
 
+# --- Health Check Endpoint ---
+# This bypasses MCP_ALLOWED_HOSTS for Docker health checks
+async def health(request):
+    """Health check endpoint - bypasses transport security."""
+    # Optionally verify Komodo connectivity
+    client, error = _get_client()
+    if error:
+        return JSONResponse({"status": "degraded", "error": error["error"]}, status_code=503)
+    return JSONResponse({"status": "ok"})
+
+
+# --- ASGI Application ---
+def create_app():
+    """Create the ASGI application with health check and MCP routes."""
+    mcp_app = mcp.http_app()
+    
+    # Wrapper app: /health bypasses security, everything else goes to MCP
+    routes = [
+        Route("/health", health, methods=["GET"]),
+        Mount("/", app=mcp_app),  # MCP handles /mcp endpoint
+    ]
+    
+    return Starlette(routes=routes)
+
+
+# Create the app instance for uvicorn
+app = create_app()
+
+
 if __name__ == "__main__":
     import uvicorn
-    uvicorn.run(mcp.sse_app, host="0.0.0.0", port=8000)
+    # Run the wrapper app (includes /health and /mcp endpoints)
+    uvicorn.run(app, host="0.0.0.0", port=8000)