context-aws-sam_skill

Overview

This skill provides a focused development context for AWS SAM serverless projects, applied when working with template.yaml, Lambda handlers, samconfig.toml, API Gateway integrations, and sam local commands. It captures conventions, common patterns, and practical checks to streamline building, testing, and deploying SAM-based applications. Use it to enforce consistent structure, naming, and local testing practices across serverless services.

How this skill works

The skill inspects project files and workflow signals to surface SAM-specific guidance: template.yaml structure, Lambda handler files, samconfig.toml settings, and local invocation commands. It highlights best practices for resource naming, function configuration, API Gateway integration shapes, and local debugging with sam local. It also references architecture and conventions to suggest adjustments or optimizations during development.

When to use it

• Creating or updating Lambda functions and their handler files
• Designing or editing template.yaml (SAM template) resources and transforms
• Configuring API Gateway integrations and HTTP APIs
• Running local tests, invoking functions, or debugging with sam local
• Tuning deployment settings in samconfig.toml and CI/CD pipelines

Best practices

• Keep template.yaml organized by grouping resources and using meaningful logical IDs
• Define clear memory/timeout settings per function and set Policies minimally
• Use environment variables and parameter mappings for stage-specific configuration
• Prefer small, single-purpose Lambdas and separate concerns across functions
• Test locally with sam local invoke and sam local start-api, mirroring production event shapes
• Use Lambda Powertools (for supported runtimes) for tracing, logging, and standardized utilities

Example use cases

• Create a new HTTP endpoint: add AWS::Serverless::Function and AWS::Serverless::Api entries in template.yaml and test with sam local start-api
• Debug a failing handler locally using sam local invoke with a sample event and attached environment variables from samconfig.toml
• Migrate an existing function to SAM: extract resource settings into template.yaml and validate IAM policies and permissions
• Configure stage-specific settings: use samconfig.toml or template parameters to manage dev/staging/prod differences
• Integrate Lambda responses with API Gateway mapping templates for custom response formats