Step Functions Agent is an open-source toolkit enabling developers to construct intelligent serverless workflows on AWS. By leveraging Large Language Models like OpenAI's GPT, this agent dynamically generates AWS Step Functions state machine definitions based on natural language prompts or structured instructions. It supports invoking Lambda functions, passing context between steps, implementing conditional branching, parallelization, retries, and error handling. The framework abstracts AWS service integrations, automatically provisions resources, and offers observability through CloudWatch. Users can customize prompts, integrate custom functions, and monitor workflow executions. With built-in fallback strategies and audit logging, Step Functions Agent streamlines building scalable, resilient AI-driven automation pipelines, accelerating development for data processing, ETL, and decision support applications.