Aws Api Gateway

Two main types: REST API (full feature set, mapping templates) and HTTP API (simplified, lower latency, lower cost). Both support route definitions, integrations, stages, and custom domains. Management API (apigateway.amazonaws.com) mirrors all console operations. SDK generation available from the API definition for client libraries. WebSocket API adds $connect/$disconnect/$default routes. Consistent JSON responses across all management operations.

Built-in throttling per stage and per-method with 429 responses. Default account-level limits (10,000 req/s) expandable via service quotas. Gateway errors return structured JSON with X-Amzn-Errortype header. Integration timeout configurable (29s for REST, 30s for HTTP). CloudWatch Logs and X-Ray tracing integration for observability. AWS SLA: 99.95% uptime guarantee. Rate limit increases via AWS support.

AWS API Gateway is the standard way to expose backend logic as APIs on AWS — Lambda functions, EC2 instances, ECS services, or external HTTP endpoints. REST API type provides full request/response transformation; HTTP API type offers lower latency and cost for simple proxy patterns; WebSocket API supports stateful connections. Key agent use case: building or consuming APIs in front of Lambda-based agent tools. The management API allows programmatic API lifecycle management. High-volume, battle-tested at AWS scale. Main friction: IAM auth and the breadth of configuration options require AWS expertise. Confidence is docs-derived.

Authorization options: IAM auth (SigV4 signed requests), Amazon Cognito user pool authorizers, Lambda custom authorizers (JWT, API key, custom logic), and API key-based usage plans. Each route can have different authorizers. Resource policies control which principals can invoke the API. VPC endpoints available for private APIs. Stage variables and usage plans allow per-consumer throttle and quota limits.

AWS documentation covers API Gateway comprehensively: REST vs. HTTP vs. WebSocket comparisons, integration types, authorizer setup, deployment stages, and monitoring. CloudFormation, CDK, SAM, and Terraform provider support for infrastructure-as-code. HTTP API getting-started guides have improved significantly. Pricing is non-trivial to estimate but well-documented. Developer portal in developer.amazonaws.com with interactive API console.