---
title: "Download the Lucis OpenAPI document (JSON)"
method: HEAD
path: "/openapi.json"
tags: ["Discovery"]
---

# Download the Lucis OpenAPI document (JSON)

`HEAD /openapi.json`

Returns the Lucis.life OpenAPI 3.1 document describing the public biomarker catalog, OAuth 2.0 token endpoint, typed errors, and rate-limit headers.

## Response `200`

OpenAPI 3.1 document.

## Other responses

- `429` — Rate limit exceeded. Honour Retry-After and RateLimit.

---

[API](https://skmtc.dev/lucis/apis/lucis-public-api.md) · [All operations](https://skmtc.dev/lucis/apis/lucis-public-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/lucis/lucis-public-api/revisions/9f890b2539af/schema)