platequery-mcp

# PlateQuery MCP — US License Plate & Vehicle Information

**License plate lookup for AI agents, built on [PlateQuery](https://platequery.com/)**
— the license plate lookup site people use to notify vehicle owners,
report bad driving, or flag illegal parking. This [Model Context
Protocol](https://modelcontextprotocol.io) server lets an agent read
those same messages for any U.S. license plate, plus public ALPR
(automated license plate reader) sighting history from the Flock Safety
camera network, by state or region.

- **Website:** https://platequery.com/
- **API docs / pricing:** https://api.platequery.com/
- **MCP endpoint:** `https://api.platequery.com/mcp` (Streamable HTTP)
- **Registry listing:** `com.platequery/plate-api` on the
  [official MCP registry](https://registry.modelcontextprotocol.io/)

This repository holds public documentation for the server. The
implementation lives in PlateQuery's main application repository, which
is closed-source.

## Tools

| Tool | Cost | Description |
| --- | --- | --- |
| `check_credits` | Free | Check your account's remaining credit balance. Doesn't count against the rate limit. |
| `lookup_plate` | 1 credit | Quick summary for one plate: privacy status, the latest 3 messages (plus a total count), and a count of ALPR mentions, if any are public. |
| `list_plate_messages` | 1 credit | Full, paginated list of messages posted about a plate. |
| `list_plate_alpr_mentions` | 1 credit | Full, paginated ALPR search history for a plate, including the searching agency and source. |

A plate marked private by its owner returns zeroed messages/mentions to
everyone except that owner. Free plan grants a starting credit balance on
signup; additional credits are purchased in bulk packages — see
[api-settings](https://platequery.com/api-settings/) for current pricing.
Paid tools are rate-limited per account; call `check_credits` as often as
you like to check balance without spending a credit.

## Authentication

The server is OAuth 2.1 only — no manual API keys. It supports PKCE and
dynamic client registration (DCR), so a compliant MCP client (Claude,
or any client following the
[MCP authorization spec](https://modelcontextprotocol.io/specification/basic/authorization))
can connect by:

1. Pointing at `https://api.platequery.com/mcp`.
2. Following the `WWW-Authenticate` challenge to discover
   `https://platequery.com` as the authorization server (RFC 9728
   protected resource metadata).
3. Registering itself dynamically (RFC 7591) and running the standard
   Authorization Code + PKCE flow.
4. Signing in with (or creating) a PlateQuery account when prompted.

No client secret or pre-issued API key is needed — sign-in happens in
the browser the first time an agent connects.

## Adding it to an MCP client

Most MCP clients (including Claude) let you add a remote server by URL.
Add `https://api.platequery.com/mcp` as a Streamable HTTP connector and
follow the sign-in prompt on first use.

## Support

Questions or issues: https://platequery.com/contact/