PlateQuery MCP — US License Plate & Vehicle Information
License plate lookup for AI agents, built on PlateQuery — the license plate lookup site people use to notify vehicle owners, report bad driving, or flag illegal parking. This Model Context Protocol 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-apion the official MCP registry
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. |
post_plate_message | Free | Post a new message about a plate -- e.g. "reported for speeding" -- optionally with vehicle make/model/year/color and an approximate location. Requires the write scope. See Posting messages below. |
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 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.
Posting messages
post_plate_message is free but deliberately conservative, since it's
the only tool that writes anything:
- Requires a PlateQuery account with a confirmed email.
- Rate-limited: 2 posts/minute, 10 posts/day, 3 posts/day about the same plate.
- Not published immediately. Every post goes into the same moderation queue a website submission does -- it's invisible (and the plate's followers aren't notified) until a human moderator approves it.
vehicle_make/vehicle_model/vehicle_year/vehicle_colorandlocationare all optional free text --locationshould be an approximate description (e.g. "Hwy 37 near Los Altos, CA" or a cross-street), never precise GPS coordinates.
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) can connect by:
- Pointing at
https://api.platequery.com/mcp. - Following the
WWW-Authenticatechallenge to discoverhttps://platequery.comas the authorization server (RFC 9728 protected resource metadata). - Registering itself dynamically (RFC 7591) and running the standard Authorization Code + PKCE flow.
- 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.
Two scopes exist: read (the default -- covers every tool except
post_plate_message) and write (required for post_plate_message,
opt-in only). A client must explicitly request write at connect time to
be able to post; an existing read-only connection can't post without
reconnecting.
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/