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CheckFitment

com.checkfitment/checkfitmentcheckfitment.comstreamable-httpv1.1.0Scanned

Bolt patterns and wheel specs by vehicle, wheel and tire fitment, spacer and gear ratio maths.

6 tools: 3 change things and 3 only read.

Tools: 0 delete, 0 irreversible, 3 write, 3 read.
  • Reads private data · 1
  • Reads text others write · 2
  • Can send data out · 0
  • No findings

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3 of these tools change something. Run those as governed actions.

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Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.

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Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

6 tools

Changes things 3Claude Code: ask
  • bolt_pattern_factsUse for "what is 5x114.3 in inches", "is 5x114.3 the same as 5x115", "will 6x135 wheels fit 6x139.7", or which vehicles use a pattern.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Use for "what is 5x114.3 in inches", "is 5x114.3 the same as 5x115", "will 6x135 wheels fit 6x139.7", or which vehicles use a pattern. Converts mm and inch notation, lists look-alike patterns that do not interchange, the vehicles in the dataset with that pattern, the lug tightening order and typical torque ranges by stud size (guidance only).

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Bolt pattern in mm and inches, look-alikes
  • gear_ratio_calculatorUse for "what does my 3.73 axle behave like on 35s", "what ratio do I need to regear for 33s", RPM at highway speed after a tire change, or the crawl ratio (with transfer-case low …Reads text others writeNo findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

    What it can reach

    • untrusted-inputThe description's first sentence says "crawl": it reads web pages, which anyone can write.
    Description, as the server wrote it
    Use for "what does my 3.73 axle behave like on 35s", "what ratio do I need to regear for 33s", RPM at highway speed after a tire change, or the crawl ratio (with transfer-case low ratio and first gear). Returns the effective ratio, RPM before and after in a 1:1 gear, the ratio that restores stock feel, the nearest gear set actually sold and how serious the change is.

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Gear ratio after a tire change, regear
  • wheel_spacer_calculatorUse for "do I need spacers", "what spacer gets +35 wheels to +20", "is a 10 mm slip-on spacer safe".No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Use for "do I need spacers", "what spacer gets +35 wheels to +20", "is a 10 mm slip-on spacer safe". A spacer lowers the effective offset by its thickness. Returns the spacer needed for a target offset (and the nearest common size), the effective offset, track change, whether it is slip-on or bolt-on territory, and, with stud, stud_protrusion_mm and wheel_pad_thickness_mm, the slip-on thread-engagement check (≥ 1 × stud diameter and ≥ 6.5 turns).

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Wheel spacer size and stud engagement
Only reads 3Show 3 read-only tools
  • bolt_pattern_lookupUse for "what is the bolt pattern on a 2019 Ford F-150", lug torque, center bore, thread size, OEM wheel size, offset or tire size of a vehicle, or "will these wheels fit my car" w…Reads private dataReads text others writeNo findings

    Why it is in this group

    • The name "bolt_pattern_lookup" says "lookup": a word for reading.

    What it can reach

    • private-dataThe description's first sentence says "thread": it reads messages.
    • untrusted-inputThe description's first sentence says "thread": it reads messages, which other people can write.
    Description, as the server wrote it
    Use for "what is the bolt pattern on a 2019 Ford F-150", lug torque, center bore, thread size, OEM wheel size, offset or tire size of a vehicle, or "will these wheels fit my car" when the vehicle is named. Looks the vehicle up in the CheckFitment dataset (a fixed set of vehicles, each spec cited to manufacturer documents and marked verified or unverified). If the vehicle or year is not in the dataset the tool says so (not_in_database / year_covered false) and gives no figures; never fill them in from memory. Optional wheel_center_bore_mm runs the hub-centric check.

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Vehicle bolt pattern and wheel specs
  • tire_size_compareUse for "what changes if I go from 265/70R17 to 285/75R17", "how far off is my speedometer with 33s", or odometer error after a tire change.No findings

    Why it is in this group

    • The name "tire_size_compare" says "compare": a word for reading.
    Description, as the server wrote it
    Use for "what changes if I go from 265/70R17 to 285/75R17", "how far off is my speedometer with 33s", or odometer error after a tire change. Returns diameter, width, sidewall and ride-height change, the true speed when the speedometer shows a given value, the odometer error and how serious it is.

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Tire size change: diameter and speedometer
  • wheel_fitment_checkUse to compare a current wheel (and tire) with a new one: how far the outer edge pokes toward the fender and the inner edge toward the suspension, the diameter and ride-height chan…No findings

    Why it is in this group

    • The description's first verb is "compare": a word for reading.
    Description, as the server wrote it
    Use to compare a current wheel (and tire) with a new one: how far the outer edge pokes toward the fender and the inner edge toward the suspension, the diameter and ride-height change, speedometer effect, backspacing, and whether the new tire width suits the new rim width. With measured clearances (outer: tire edge to fender lip; inner: to the nearest suspension part, both on the current setup) it returns fits / tight / rub. Leave the tire fields out for a wheel-only offset comparison.

    Annotations the server declares

    • readOnlyHint: true
    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: false
    • title: Will these wheels (and tires) fit

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged outbound.

Reads private data1
Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write2
Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
Can send data out0
Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Findings

Matches of fixed checks, with the text they matched.

No check matched anything in these tool definitions. That is not a safety guarantee.

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 1.1.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http checkfitment https://checkfitment.com/mcp?src=mcp
claude mcp add --transport http checkfitment https://checkfitment.com/mcp?src=mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__checkfitment__bolt_pattern_lookup",
      "mcp__checkfitment__wheel_fitment_check",
      "mcp__checkfitment__tire_size_compare"
    ],
    "ask": [
      "mcp__checkfitment__wheel_spacer_calculator",
      "mcp__checkfitment__gear_ratio_calculator",
      "mcp__checkfitment__bolt_pattern_facts"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as checkfitment. Review it before you use it.

Capability tags behind 2 rules
  • mcp__checkfitment__bolt_pattern_lookup private-data, untrusted-input
  • mcp__checkfitment__gear_ratio_calculator untrusted-input

Pin

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/com.checkfitment/checkfitment/verify?hash=b5f0ceebf96b5ab3c1b4d24c77b897c75b302ce6a3ba6373d5955d20bde88fd9" | jq -e '.changed == false'

Pinned hash b5f0ceebf96b, from Oct 24, 2026, 13:17 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/com.checkfitment/checkfitment/changes.xml

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Badge

anlyon.dev badge for com.checkfitment/checkfitment
[![anlyon.dev](https://anlyon.dev/badge/com.checkfitment/checkfitment.svg)](https://anlyon.dev/servers/com.checkfitment/checkfitment)

Source: MCP Registry. Synced Oct 24, 2026, 13:17 UTC.