Protocol
OpenAPI Specification
Definition
A standard for describing REST APIs in a machine-readable format (JSON or YAML). In the agent context, OpenAPI specs serve as the bridge between traditional APIs and agent tool use — agents can parse an OpenAPI spec to understand available endpoints, parameters, and response formats, then invoke them as tools. Many MCP servers are auto-generated from OpenAPI specs.
Builder Context
If your service has an OpenAPI spec, you're already halfway to agent-readiness. Tools like openapi-to-mcp can auto-generate MCP servers from your spec. When writing OpenAPI descriptions for agent consumption, be more descriptive than you would for human developers — agents rely heavily on operation descriptions and parameter documentation to decide when and how to call endpoints.