# APIs.json

**Canonical:** https://apis.io/providers/apis-json/  
**Website:** https://apisjson.org  
**APIs profiled:** 1

APIs.json is an open, machine-readable specification that API providers can use to describe their API operations, similar to how websites use sitemap.xml. The format provides a lightweight means for individuals and organizations to document the location of their APIs, associated descriptions, human and machine-readable specifications, and ancillary information such as licensing, maintainers, and terms of service. It was created by Kin Lane and Steven Willmott in May 2014 and is maintained as an open IETF-style draft. The current stable version is 0.19, published in November 2024. APIs.json files can be placed at the root of any domain as /apis.json or /apis.yml for automated discovery. The specification defines root-level fields (name, description, url, apis, common), API-level fields (aid, humanURL, baseURL, tags, properties), and a comprehensive list of property types covering documentation, authentication, licensing, support, and governance. It is the foundation for the APIs.io search engine and API Commons initiative.

## Kin Score — 22.3 / 100 (emerging)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 22.3).

| Facet | Score |
|---|---|
| Discoverability | 59.3 |
| Contract Quality | 29.6 |
| Governance | 25.0 |
| Contract Governance | 25.0 |
| Operational Transparency | 10.5 |
| Developer Ergonomics | 7.1 |
| Commercial Clarity | 15.8 |
| Access Clarity | 15.8 |

## Agent readiness — 3.0 (human-only)

| Dimension | Value |
|---|---|
| Spec Presence | no |
| Agentic Access | no |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | no |
| Idempotency | no |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |

## Access

Freemium — onboarding: unknown, pricing: freemium, trial: no (confidence: medium).

## APIs (1)

- **APIs.json Specification** — The APIs.json specification defines a machine-readable JSON or YAML format for describing API operations. Unlike OpenAPI which describes the technical interface of a single API,...

## Security (1)

- **Apis Json Domain Security** — TLSv1.3

## Plans (1)

- **Apis Json Plans Pricing**

## Use cases (6)

- **API Discovery** — API providers publish APIs.json files at their domain root so that search engines like APIs.io can automatically discover and index all their APIs without manual submission.
- **API Governance** — Platform teams use APIs.json as a canonical machine-readable index of their API portfolio, enabling automated compliance checking of required operational properties like terms o...
- **API Portal Generation** — Developer portals can be automatically generated from APIs.json files by reading the properties array and presenting documentation, OpenAPI specs, getting started guides, and ot...
- **API Commons Participation** — Organizations publish APIs.json files to participate in the API Commons initiative, making their APIs discoverable and accessible to a wider developer community.
- **Internal API Catalog** — Enterprises use APIs.json as the foundation for internal API catalogs, enabling discoverability of internal, partner, and public APIs using a consistent machine-readable format.
- **Backstage Integration** — Teams use the APIs.json Backstage integration to import API metadata from APIs.json files into Spotify Backstage for internal developer portal use.

## Tags

API Aggregation, API Cataloging, API Commons, API Discovery, API Governance, API Operations, Machine-Readable, Specification, Standard

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/apis-json/). Scores are computed from the provider's own public artifacts under a published rubric.