Playground API — Free Stateful Mock REST & GraphQL Service

Playground REST API

Free stateful mock REST API with session-scoped mutation overlays, dynamic collections, media generators, chaos simulation, and simulated JWT auth. Canonical HTTPS base is playground.nileslabs.com/api/v1 (OpenAPI/Postman servers value declares a raw Vercel origin).

GitHub OpenAPI

Documentation

📖
Documentation
https://playground.nileslabs.com/docs

Specifications

⚙
OpenAPI
https://playground.nileslabs.com/api/v1/downloads/openapi.json

Other Resources

🔗
PostmanCollection
https://playground.nileslabs.com/api/v1/downloads/postman.json
🔗
LLMsTxt
https://playground.nileslabs.com/llms.txt
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/playground/refs/heads/main/apis.yml

Work with this as data

Every API here is available over the APIs.io API and to AI agents over MCP.

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Tools for apis

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  • find_apisBrowse and filter every API in the catalog.
  • get_api_artifactsOne API's artifacts, grouped by type.
  • get_openapiThe primary OpenAPI for this API.
  • find_similar_apisAPIs that look like this one.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
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Call it yourself

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This API 
curl "https://apis.io/api/v1/apis/playground-rest-api"
All apis 
curl "https://apis.io/api/v1/apis?limit=25"

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OpenAPI Specification

openapi.json Raw ↑