aws-step-functions

AWS Step Functions

Overview

AWS Step Functions uses Amazon States Language (ASL) to define state machines as JSON. With AWS Step Functions, you can create workflows, also called state machines, to build distributed applications, automate processes, orchestrate microservices, and create data and machine learning pipelines.

This skill provides comprehensive guidance for writing state machines in ASL, covering:

• ASL structure and JSONata expression syntax
• Details on the eight available workflow states
• The $states reserved variable
• Workflow variables with Assign
• Error handling
• AWS Service integration patterns
• Example code for data transformation and architecture
• Validation and testing of state machines
• How to migrate from JSONPath to JSONata

The AWS MCP server is recommended for sandboxed execution and audit logging when following this skill, but all steps use AWS CLI syntax and work without it.

When to Load Reference Files

Load the appropriate reference file based on what the user is working on:

• ASL structure, state types, Task, Pass, Choice, Wait, Succeed, Fail, Parallel, Map → see references/asl-state-types.md
• Error handling, troubleshooting, Retry, Catch, fallback, error codes, States.Timeout, States.ALL → see references/error-handling.md
• Service integrations, Lambda invoke, DynamoDB, SNS, SQS, SDK integrations, Resource ARN, sync, async → see references/service-integrations.md
• Migrating from JSONPath to JSONata, migration, JSONPath to JSONata, InputPath, Parameters, ResultSelector, ResultPath, OutputPath, intrinsic functions, Iterator, payload template → see references/migrating-from-jsonpath-to-jsonata.md
• Validation, linting, testing, TestState, test state, mock, mocking, unit test, inspection level, DEBUG, TRACE, validate state, test in isolation → see references/validation-and-testing.md
• Architecture patterns, examples, polling, saga, compensation, scatter-gather, semaphore, lock, human-in-the-loop, escalation, Express to Standard → see references/architecture-patterns.md
• Data transformation, JSONata expressions, filtering, aggregation, string operations, $reduce, $lookup, $toMillis, $partition, $parse, $hash, $uuid → see references/transforming-data.md
• State input/output, $states, Assign, Output, Arguments, variable scope, variable limits, evaluation order, passing data between states → see references/processing-state-inputs-and-outputs.md