MCPFax Vehicle Diagnostics

A fault code, a VIN, or a recall — answered from public NHTSA and standards data.

CommunityDegradedNo sign-inGlobalFreeRead-only

What it can do

    What data it sees

    Do you need an account

    No: the server works without sign-in

    A fault code, a VIN, or a recall — answered from public NHTSA and standards data.

    How to connect

    How to connect MCPFax Vehicle Diagnostics to Claude

    The server address to paste into Claude settings:

    https://mcpfax-diag.bowling-anthony.workers.dev/mcp

    1. Open Claude (claude.ai or the desktop app).
    2. Go to Settings → Connectors.
    3. Click Add custom connector.
    4. Paste the server address copied below into Remote MCP server URL and click Add.
    5. In a chat, click + → Connectors and switch the new connector on.

    Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

    Authorization

    After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

    How to connect MCPFax Vehicle Diagnostics to ChatGPT

    The server address to paste into ChatGPT settings:

    https://mcpfax-diag.bowling-anthony.workers.dev/mcp

    1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
    2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
    3. Open Settings → Connectors and click Create.
    4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
    5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
    6. In a new chat open + → Apps/Connectors and enable the connector.

    OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

    Authorization

    On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

    How to connect MCPFax Vehicle Diagnostics to Cursor

    The server address to paste into Cursor settings:

    https://mcpfax-diag.bowling-anthony.workers.dev/mcp

    Fastest: click Open in Cursor below and confirm the prompt.

    Manually:

    1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
    2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
    3. Save the file. The server appears in the MCP list; authorize it there if asked.

    Authorization

    If the service needs sign-in, an authorize button appears next to the server in the MCP list.

    Server tool list (4)

    Raw names from tools/list. Only developers need these.

    dtc_lookupLook up what a vehicle fault code (OBD-II diagnostic trouble code) means. Returns a reworded definition compiled from open/public sources (with the source and licence per row) plus which makes define the code specifically. Pass 'make' for the make-specific meaning instead of the generic SAE one — the same code can mean different things on different brands. Use this when a scan tool reported a code like P0301, B1318 or U0100; we never guess a meaning (unknown codes return not_found). Descriptions are compilations, not manufacturer verbatim strings, and severity is not guaranteed. Costs $0.006 USDC per call via x402 on Base.
    vehicle_recallsOfficial NHTSA safety recalls for a vehicle. Returns campaign id, affected component, the safety consequence, and the free remedy, newest first (max 50). Query by make (optionally model and year) or by a known campaign id. Use this before buying a used vehicle or when a customer asks whether their car has open recalls. A zero count means nothing matched the ingested NHTSA subset — it does not prove the vehicle is recall-free. Costs $0.005 USDC per call via x402 on Base.
    vehicle_tsbsNHTSA Technical Service Bulletins (manufacturer repair guidance for known defects that are not safety recalls). Returns bulletin id, summary, and the fault codes each bulletin names (max 50). Query by make/model/year, or by fault code to find bulletins that address that specific code. Use this after dtc_lookup when you want the manufacturer's documented fix. A zero count means nothing matched the ingested subset. Costs $0.005 USDC per call via x402 on Base.
    vin_decodeDecode a Vehicle Identification Number into make, model, model year, body class, engine and plant country using NHTSA's public vPIC database. Use this when you have a VIN and need the exact vehicle before looking up recalls or bulletins. Costs $0.005 USDC per call via x402 on Base.