name: Playground API — Free Stateful Mock REST & GraphQL Service
description: >-
  A free, zero-configuration, stateful mock REST and GraphQL API sandbox by Nilesh Kumar / Niles Labs. Unlike static
  mock APIs, it provides stateful per-session virtual mutation overlays where POST/PUT/PATCH/DELETE mutations persist
  across GET queries within a session, while the global baseline dataset remains read-only. Includes chaos/network
  simulation, dynamic collections, avatar/thumbnail generators, and simulated JWT auth loops. MIT licensed, no auth or
  signup required.
url: >-
  https://raw.githubusercontent.com/api-evangelist/playground/refs/heads/main/apis.yml
created: '2026-09-14'
modified: '2026-09-14'
specificationVersion: '0.21'
tags:
  - developer-tools
  - testing
  - mock-api
  - api-sandbox
  - rest
  - graphql
  - e2e-testing
apis:
  - name: Playground REST API
    description: >-
      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).
    humanURL: https://playground.nileslabs.com/docs
    baseURL: https://playground.nileslabs.com/api/v1
    tags:
      - developer-tools
      - testing
      - mock-api
      - api-sandbox
      - rest
      - graphql
      - e2e-testing
    properties:
      - type: OpenAPI
        url: https://playground.nileslabs.com/api/v1/downloads/openapi.json
      - type: PostmanCollection
        url: https://playground.nileslabs.com/api/v1/downloads/postman.json
      - type: Documentation
        url: https://playground.nileslabs.com/docs
      - type: LLMsTxt
        url: https://playground.nileslabs.com/llms.txt
  - name: Playground GraphQL API
    description: >-
      GraphQL gateway providing stateful mock query and mutation access to the same dataset, with an interactive
      explorer.
    humanURL: https://playground.nileslabs.com/docs/graphql
    baseURL: https://playground.nileslabs.com/api/v1/graphql
    tags:
      - developer-tools
      - testing
      - mock-api
      - api-sandbox
      - rest
      - graphql
      - e2e-testing
    properties:
      - type: GraphQL
        url: https://playground.nileslabs.com/api/v1/graphql
      - type: Documentation
        url: https://playground.nileslabs.com/docs/graphql
maintainers:
  - FN: Nilesh Kumar
    url: https://nileslabs.com
x-generated:
  by: apis.io/add
  model: claude-opus-4-8
  confidence: 97
  at: '2026-09-14T09:54:24.885Z'
common:
- type: Website
  url: https://playground.nileslabs.com
- type: GettingStarted
  url: https://playground.nileslabs.com/docs/quickstart
- type: SourceCode
  url: https://github.com/nileslabs/playground_api
- type: GitHubOrganization
  url: https://github.com/nileslabs
- type: AgentSkill
  url: skills/_index.yml
- type: Overlay
  url: overlays/playground-openapi-overlay.yaml
- type: ToolCrosswalk
  url: mcp/playground-tool-crosswalk.yml
- type: MCPServer
  url: mcp/playground-mcp.yml
- type: Packages
  url: packages/playground-packages.yml
- type: Sandbox
  url: sandbox/playground-sandbox.yml
- type: Conformance
  url: conformance/playground-conformance.yml
- type: Plans
  url: plans/playground-plans-pricing.yml
- type: RateLimits
  url: rate-limits/playground-rate-limits.yml
- type: DataModel
  url: data-model/playground-data-model.yml
- type: Lifecycle
  url: lifecycle/playground-lifecycle.yml
- type: ErrorCatalog
  url: errors/playground-problem-types.yml
- type: Conventions
  url: conventions/playground-conventions.yml
- type: Authentication
  url: authentication/playground-authentication.yml
- type: DomainSecurity
  url: security/playground-domain-security.yml
x-enrichment:
  date: '2026-09-14'
  status: enriched
  artifacts_added: 23
  pass: local-v3