AWS Serverless

Builds, deploys, manages, debugs, configures, and optimizes serverless applications on AWS using Lambda, API Gateway, Step Functions, EventBridge, and SAM/CDK.

2 minutes · 473 words · 4 sections

Domain expertise for building serverless applications on AWS: Lambda, API Gateway, Step Functions, EventBridge, event source mappings, concurrency, cold starts, deployment, and troubleshooting.

Works best with the AWS MCP server (opens in a new tab) — run CLI commands, query CloudWatch, validate configs directly. All guidance also works with standard AWS CLI access.

Specialized skills — check these first

These cover capabilities and procedures the general references below do not. Several are specialized features or step-by-step tested procedures you would otherwise miss. Route to the matching skill before falling back to the references.

Advanced Lambda compute (easy to overlook)

Use this skill	When the workload involves
aws-lambda-microvms	Strong tenant isolation, sandboxed/untrusted code execution (AI agent code sandboxes, REPLs, notebooks, CI runners), long-lived sessions, suspend/resume with preserved state, port-listening servers (gRPC, WebSocket, custom TCP), Firecracker microVMs, snapshot-resumable compute, up to 8-hour lifetimes
aws-lambda-durable-functions	Durable execution, checkpoint-and-replay, long-running multi-step workflows written as plain code (TS/Python/Java), automatic state persistence, saga pattern in code, human-in-the-loop callbacks, executions up to 1 year, `context.step`/`context.wait`/`context.invoke`, `withDurableExecution`, `durable-execution-sdk`
aws-lambda-managed-instances	Lambda Managed Instances (LMI), capacity providers, EC2-backed Lambda, steady high-volume traffic (50M+ req/mo) wanting Savings Plans / Reserved Instance pricing, `PerExecutionEnvironmentMaxConcurrency`, `CapacityProviderConfig`, multi-concurrent execution environments

Step-by-step task procedures (tested CLI SOPs)

Use this skill	For the task
connecting-lambda-to-api-gateway	Wire an existing Lambda to a new REST/HTTP API: proxy integration, permissions, CORS, throttling, access logging, deployment
connecting-lambda-to-dynamodb	Connect Lambda to DynamoDB: IAM execution role, read/write permissions, stream event source mapping
creating-api-gateway-stage	Create an API Gateway stage with CloudWatch logging, X-Ray tracing, throttling, WAF association, and authorization
deploying-custom-domain-rest-api	Deploy a Regional REST API with custom domain: ACM cert, Lambda backend, request authorizer, base path mapping, Route 53 DNS
debugging-lambda-timeouts	Systematically diagnose a timing-out Lambda: config, CloudWatch logs/metrics, VPC, cold starts, memory, downstream calls
processing-s3-uploads-with-step-functions	Deploy an event-driven workflow: S3 upload → EventBridge → Step Functions → Lambda (small files) or Fargate (large files), with VPC/ECR/ECS/IAM

Routing (general references in this skill)

User need	Read
Building a new serverless app — pattern selection	architecture.md (opens in a new tab)
Lambda config, cold starts, SnapStart, memory, VPC, layers, Function URLs	lambda.md (opens in a new tab)
Concurrency (reserved, provisioned, ESM controls)	concurrency.md (opens in a new tab)
Event sources (SQS, DynamoDB Streams, SNS, Kinesis), filtering, batch failures	event-sources.md

Note: Reference files contain specific runtime versions, quotas, and feature matrices that change. When precision matters (production, runtime choice, quotas), confirm against current AWS documentation. The references focus on values and gotchas that are easy to get wrong — not on basics.

Appendix 42.1–42.10

10 files · 65 KB

Everything this skill ships beside its prose. All of it is set here, as subchapters of chapter 42.

ReferencesMarkdown · 9 files

Documentation the agent loads on demand, rather than up front.

AssetsPython · 1 file

Templates, schemas and fixtures the skill draws on.

42.10Powertools Handlerassets/powertools-handler.py2 KB

Install this repository

$ npx skills add aws/agent-toolkit-for-aws

» /plugin marketplace add aws/agent-toolkit-for-aws

Skills install per repository, not per chapter — the CLI has no documented per-skill form, so we do not print one.

About this skill

Trigger

Builds, deploys, manages, debugs, configures, and optimizes serverless applications on AWS using Lambda, API Gateway, Step Functions, EventBridge, and SAM/CDK. Covers cold starts, CORS debugging, event source mappings, troubleshooting, concurrency, SnapStart, Powertools, function URLs, EventBridge Scheduler, Lambda layers, and production readiness. Triggers on mentions of Lambda, API Gateway, Step Functions, SAM templates, CDK serverless stacks, DynamoDB stream triggers, SQS event sources, cold starts, timeouts, 502/504 errors, throttling, concurrency, CORS, Powertools, or any event-driven architecture on AWS, even without the word "serverless." Does not apply to EC2, ECS/Fargate containers, or Amplify hosting.

The verbatim description from this skill’s front matter — the string an agent matches on to decide whether to load it.

Also published for: Alternate — collapsed into this chapter because the copies are the same skill.
Source: skills/core-skills/aws-serverless/SKILL.md

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How this issue was made

Source: github.com/aws/agent-toolkit-for-aws, branch main, last pushed 10 August 2026.
Licence: Apache-2.0 — the text of every chapter is reproduced unmodified, frontmatter included, under the upstream licence.
Discovery: 120 chapters found by walking the repository tree for SKILL.md, not by matching a directory convention. 17 distinct layouts observed: plugins/aws-agents-for-devsecops/skills/*/SKILL.md, plugins/aws-agents/skills/*/SKILL.md, plugins/aws-core/skills/*/SKILL.md, skills/core-skills/*/SKILL.md, skills/specialized-skills/analytics-skills/*/SKILL.md, skills/specialized-skills/database-skills/*/SKILL.md, skills/specialized-skills/ec2-skills/*/SKILL.md, skills/specialized-skills/messaging-and-streaming-skills/*/SKILL.md, skills/specialized-skills/migration-and-modernization-skills/*/SKILL.md, skills/specialized-skills/networking-and-content-delivery-skills/*/SKILL.md, skills/specialized-skills/operations-skills/*/SKILL.md, skills/specialized-skills/resilience-skills/*/SKILL.md, skills/specialized-skills/security-and-identity-skills/*/SKILL.md, skills/specialized-skills/serverless-skills/*/SKILL.md.