HTTP API · operational

JSONPlaceholder

Fake REST resources (posts, comments, users, todos, albums, photos) that accept GET/POST/PUT/DELETE, no key required.

JSONPlaceholder serves a stable set of fake REST collections an agent can read and pretend to write to. Useful as a fixture when testing pagination, nested resources, query filters and write verbs without touching a real service: GET /posts, /posts/1/comments, /users, /todos, /albums, /photos; POST/PUT/PATCH/DELETE are accepted and answered realistically but never persist.

endpoint: https://jsonplaceholder.typicode.com/todos/1
auth: none
try it: tested example call
curl -s https://jsonplaceholder.typicode.com/todos/1
capabilities: read fake rest resources · test pagination and filters · test write verbs without side effects · generate sample json data
tags: test · testing · fixtures · mock · rest · devtools
pricing: Free, no account.
i/o: HTTP GET/POST/PUT/PATCH/DELETE with JSON body → JSON
docs: https://jsonplaceholder.typicode.com/guide/
machine-readable: /api/public/registry/jsonplaceholder-api

Follow this tool

Get an alert when JSONPlaceholder goes down, comes back, or quietly changes shape (response schema or tool list). Free for up to 3 tools. Pro: 100 tools + webhooks for your agents.

Get a key in one call

No account, no card

100 calls/day anonymous · 1,000/day with this free key · 50,000/day on Agent Pro. The key is returned instantly in the response — send it as the x-api-key header on any /api/public/* request. The key also lets you follow up to 3 tools and get an alert when one goes down or quietly changes shape. Email is optional; add yours to receive alerts, then confirm them from your inbox.

tested example call

curl -s -X POST https://agentnexus.app/api/public/keys \
  -H 'content-type: application/json' \
  -d '{"agent":"my-agent","purpose":"tool discovery","email":"you@example.com"}'

Use it from your agent

Point any MCP-capable agent (Claude, Cursor, your own) at the no-auth endpoint — it can then find JSONPlaceholder and every other listed interface on its own:

tested example call

claude mcp add --transport http agent-nexus https://agentnexus.app/api/public/mcp

Agents can discover JSONPlaceholder through the Agent Nexus MCP server, /llms.txt or the discovery API.