# The MCP Census developer portal

MCP Census developer resources at https://mcpcensus.com/developers.

Product: **The MCP Census** (also MCP Census, mcpcensus). Domain: https://mcpcensus.com. Contact: info@mcpcensus.com.

## Quickstart

1. Optional key: https://mcpcensus.com/account — header `x-api-key`.
2. Agents: add MCP `https://api.mcpcensus.com/mcp` (see https://mcpcensus.com/agent-setup/prompt.md).
3. REST: `GET https://api.mcpcensus.com/v1/search?q=` then `POST /v1/preflight` with one exact canonical name.
4. Stop on BLOCK. Ask a human on REVIEW. Never install from a Census result alone.

## Developer resources

- Human API docs: https://mcpcensus.com/api
- OpenAPI spec: https://mcpcensus.com/openapi.json
- Auth / API keys: https://mcpcensus.com/account
- MCP server: https://api.mcpcensus.com/mcp
- Webhooks (watches): https://mcpcensus.com/api#watch
- Agent instructions (when to use): https://mcpcensus.com/agent-instructions.md
- Agent map: https://mcpcensus.com/llms.txt
- Policies: https://mcpcensus.com/policies

## Sandbox

No separate staging host. The live MCP Census API is the sandbox.

- Anonymous: 10 unique lookups/day per IP
- Free account key: 100 unique lookups/day
- Unmetered: `/v1/stats`, `/v1/recent`, `/v1/coverage`, `/v1/policies`

```
curl -s https://api.mcpcensus.com/v1/stats
curl -s "https://api.mcpcensus.com/v1/search?q=github"
curl -s https://api.mcpcensus.com/v1/policies
```

## Auth

Keys are minted on the account page. Send `x-api-key`. Anonymous works until the daily cap. Lost keys are emailed, never shown in page HTML.

## Webhooks

`POST https://api.mcpcensus.com/v1/watch` (API key). Events only on observed transitions: `remote_down` / `remote_up`, `health_change`, `verified_change`, `security`. Headers: `X-Census-Event`, `X-Census-Signature` (sha256 HMAC), `X-Census-Watch-Id`.