Hector AI is an open-source, MIT-licensed framework for building, deploying, and federating AI agents using pure YAML configuration. It supports zero-code agent definition, built-in metrics and tracing with Prometheus and OpenTelemetry, guardrails for security including prompt injection detection and PII redaction, RAG capabilities with vector databases, A2A protocol for peer-to-peer agent communication, and deployment on-premise or cloud without lock-in. Features include hot reload, studio mode for debugging, and workflow agents for complex behaviors.