AWS Sam

AWS SAM

MCP Tools

• sam_init - Create new SAM app
• sam_build - Build SAM app
• sam_deploy - Deploy SAM app
• sam_logs - Fetch deployed app logs
• sam_local_invoke - Locally invoke Lambda function

Project Structure

├── infrastructure/
│   ├── cloudformation/
│   └── lambda/
│       └── api/
│           ├── app.py
│           └── requirements.txt
└── template.yaml

Key Rules

• ALWAYS use SAM resource types (AWS::Serverless::Function, etc.)
• ALWAYS use Lambda Powertools via Layers, NEVER add to dependencies
• ALWAYS use version locking for dependencies
• ALWAYS create separate Lambda functions for each API
• Do NOT add boto3/botocore to dependencies (included in runtime)
• Use SAM policy templates for IAM permissions
• Add .aws-sam to .gitignore

Create New App Workflow

1. sam_init with chosen runtime
2. Restructure: move functions to infrastructure/lambda/
3. Update CodeUri paths in template.yaml
4. sam_build to verify

MCP Server Config

{
  "mcpServers": {
    "aws-sam": {
      "command": "uvx",
      "args": ["awslabs.aws-serverless-mcp-server@latest"],
      "env": {
        "AWS_PROFILE": "default",
        "AWS_REGION": "us-east-1"
      }
    }
  }
}

Prerequisites: SAM CLI installed, optionally Docker/Finch.