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RegTail MCP server

Which MCP servers are RegTail's own, from the official registry and from asking its own domain, whether they answer, and what they offer. A program checked each of these, nobody copied them from a product page.

read 2026-10-25

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Whose server it is
  • Registry namecom.regtail/regtailverified in the MCP registry

The registry name sits under regtail.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

When we asked itchecked 2026-10-25
  • Stateanswerschecked 2026-10-25
  • Tools10
  • Server calls itselfRegTail
  • Protocol version2025-06-18

On 2026-10-25 the server answered initialize and tools/list without a sign-in. First answer in 202 ms.

Should an agent connect itConnect it
  • Its tools do every use case we checked: Check a used car's MOT history before buying; Prepare questions and a checklist for a car viewing.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

Measured dailydaily checks: 10, the first on 2026-10-25
  • INITE MCP score99 of 100answers 100 · does the job 100 · definitions 97 · context 100 · connects 100
  • What an agent can do with it2 of 2 use cases
  • Answered100% of days10 of 10 daily checks
  • Median first answer201 ms
  • Space in an agent's context≈ 1,706 tokensthe definitions of all its tools (10), which an agent carries on every turn
  • Tool definitionsA · 97 of 100
  • Typed results10 of 10 toolsdeclared outputSchema: results come typed, read once
  • Parameters without a description: in 2 of 10

What an agent can do with it

  • can do · Check a used car's MOT history before buying
  • not sure · Compare a seller's advert claims against DVSA records
  • can do · Prepare questions and a checklist for a car viewing

Each of the product's use cases, put to Jev against this server's tool list: can an agent do it with these tools?

Worth a look

None of the five warning signs in these definitions.

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (25%), doing the product's job (25%), definitions (20%), context (10%), use (10%) and how readily a client connects (10%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

Tools it offers10 tools · read 2026-10-25
  • decode_plate

    When a UK plate of this format could have been issued, from the plate alone (format, age identifier, and the window as first and last month). Offline: it does not look the car up; use free_check for that. No account needed.

  • free_check

    The site's free check: identity, tax and MOT status, latest MOT test, its defects and recorded mileage, the existing since-previous-test summary and mileage-unverified flag. Includes presentation, up to three questions from these free…

  • resolve_vehicle

    Resolve a typed plate, car photo data URL or supported advert URL to a plate only. No account or spend. If uncertain, ask the user to confirm; if unavailable, ask for the typed plate. Then use free_check.

  • compare_vehicles

    Compare the site's free projections for exactly two plates: identity, status and latest MOT test. Duplicate plates use one lookup. Includes questions from free facts, comparison image and report links. No prediction-based ranking…

  • sample_report

    The detailed report and viewing advice for one public sample car (CX52HHM, a 2002 Land Rover Defender), to show what a detailed report contains. Use when the user asks what RegTail's detailed report looks like. No account needed. It is…

  • full_report

    The detailed report of a car the user has unlocked on their RegTail account: verdict and top risks, every MOT test with defects and advisories, mileage analysis, recurring advisories, other sections, the viewing checklist, what was not…

  • unlock_report

    Spends one of the user's RegTail credits to unlock the detailed report for this plate for 30 days, then returns the detailed report (as full_report does). Ask the user first, every time, and call this only after they agree; never unlock…

  • viewing_advice

    Advice for viewing an unlocked car in person: a summary, priorities to check (each with why and the report records behind it) and known weak spots of the model. Needs the user's RegTail account linked and the plate unlocked; never spends.

  • credits_balance

    How many credits the user's RegTail account holds, and pricing_url, a page explaining how credits work. Needs the user's RegTail account linked.

  • my_reports

    The cars the user has unlocked (with when each unlock ends) and their recent checks, so a conversation can pick up a car checked earlier. Needs the user's RegTail account linked.

How to connect

Add the server to your MCP client config. Claude Desktop, Cursor and most other clients read this shape:

{
  "mcpServers": {
    "regtail": {
      "type": "http",
      "url": "https://regtail.com/mcp"
    }
  }
}

Add it

Claude Code, in a terminal

claude mcp add --transport http regtail https://regtail.com/mcp

Add to CursorAdd to VS Code

claude.ai, ChatGPT and other clients: add https://regtail.com/mcp as a custom connector in the settings.

OpenAPI spec

5 paths, read 2026-10-25. Open the spec ↗

Each line is something a program found when it went looking: the registry entry, the server's own answer, a spec that parses. A missing line means we did not find it, not that it does not exist.