AWS Lambda MCP Server

MCP server running on AWS Lambda using awslabs/mcp-lambda.

Requirements

• Terraform >= 1.14
• Docker
• AWS CLI

Deploy

Note: Lambda requires an ECR image to exist before creation. This creates a chicken-and-egg problem:

• ECR repository must be created first via Terraform
• Docker image must be pushed before Lambda can be created
• Therefore, initial deployment requires multiple steps (subsequent updates only need terraform apply)

1. Create ECR Repository

cd terraform
terraform init
terraform apply -target=module.lambda_mcp.aws_ecr_repository.lambda_mcp

2. Build & Push Docker Image

ECR_REPO=$(terraform output -raw ecr_repository_url)
aws ecr get-login-password | docker login --username AWS --password-stdin ${ECR_REPO%/*}
docker build -t mcp-server ..
docker tag mcp-server ${ECR_REPO}:latest
docker push ${ECR_REPO}:latest

3. Deploy Lambda

terraform apply

Subsequent Updates

After initial deployment, just push a new image and run terraform apply:

docker build -t mcp-server ..
docker tag mcp-server ${ECR_REPO}:latest
docker push ${ECR_REPO}:latest
terraform apply

Security

⚠️ Warning: This deployment uses Lambda Function URL with authorization_type = "NONE", meaning the endpoint is publicly accessible. For production use, consider enabling IAM authentication or adding other security measures.

MCP Client Config

{
  "mcpServers": {
    "aws-api": {
      "url": "<terraform output function_url>"
    }
  }
}

Test with curl

FUNCTION_URL=$(terraform output -raw function_url)

# Initialize
curl -X POST "$FUNCTION_URL" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "initialize",
    "params": {
      "protocolVersion": "2024-11-05",
      "capabilities": {},
      "clientInfo": {
        "name": "test-client",
        "version": "1.0.0"
      }
    }
  }'

# List available tools
curl -X POST "$FUNCTION_URL" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{"jsonrpc": "2.0", "id": 2, "method": "tools/list"}'

License

Apache-2.0