Where to find the OpenAPI spec and API docs
HIIE publishes machine-readable and human-readable documentation so both developers and agents can discover and use the API.
OpenAPI specification
The full OpenAPI description of the v1 API is served at /.well-known/openapi.json. It is OpenAPI 3.1.0, titled "HIIE v1 API" version 1.0.0, with a single bearer security scheme (your hk_live_ API key). Operations are grouped under the tags Projects, Build, CAD, Flows, and Artifacts, and each operation declares the scope it requires via an x-required-scope extension — so you can see at a glance whether a call needs read, write, or build.
Human-readable docs
The API docs are also available in markdown at /api.md. For authentication specifically, /auth.md documents the API-key method that headless agents use.
Agent-readiness surfaces
HIIE exposes several standards-based discovery endpoints under /.well-known/:
openapi.json— the OpenAPI 3.1 spec for/api/v1.api-catalog— an RFC 9727 linkset of available APIs.mcp/server-card.json— the MCP server card (SEP-1649).oauth-protected-resourceandoauth-authorization-server/openid-configuration— RFC 9728 / RFC 8414 metadata pointing at the Clerk issuer for interactive auth.- An agent-skills index with per-skill SKILL.md files.
Availability note
These agent-facing text and JSON surfaces (openapi.json, api-catalog, the MCP server card, the markdown mirrors, oauth metadata, and the skills index) are served in production and return 404 outside it — so test discovery against the production host.