Is the Renzy Plumbers MCP server safe?

No scan can promise that. What its definitions show: 4 tools, 4 of which can change, send or delete something, and 0 findings from fixed checks. Allow the reads, ask before each change, and deny the deletes; the permissions block on this page does that.

Can the Renzy Plumbers MCP server delete data?

Yes. 1 tool can delete, cancel or revoke something: order_installation.

Can the Renzy Plumbers MCP server do things that cannot be undone?

No tool is classed as irreversible: none of them sends, pays, publishes or merges, going by their definitions.

What tools does the Renzy Plumbers MCP server have?

4 tools: 1 destructive, 3 write. order_installation, check_availability, book_plumber and quote_installation.

Does the Renzy Plumbers MCP server need sign-in or OAuth?

Its remote endpoint listed its tools to an anonymous client, without sign-in.

Does the Renzy Plumbers MCP server send data to outside services?

1 tool can carry data out (it sends, posts or publishes, or takes a recipient, channel or URL): book_plumber.

Has the Renzy Plumbers MCP server changed its tools?

Not since anlyon.dev started tracking it. Last scanned Nov 7, 2026.

Renzy Plumbers MCP server

uk.co.renzy/plumbersrenzy.co.ukstreamable-httpv1.3.0Scanned 7 days ago

Book a Renzy plumber in London, or price a new boiler or air conditioning.

4 tools: 1 can delete or cancel things and 3 change things.

Reads private data · 0
Reads text others write · 2
Can send data out · 1
No findings

Tools listed without sign-in. Remote posture

With Anlyon

1 tool here can delete or cancel things. Govern it.

Anlyon lists the tools and adopts none.
Each tool you adopt gets approvals and receipts.
Your agent never holds the key.

Govern this server →

A tool your agent calls directly is not routed through Anlyon and is not governed by it. anlyon.dev only lists and labels, and these labels are the same either way.

What the Renzy Plumbers MCP server can do

The Renzy Plumbers MCP server is published by renzy.co.uk, a domain the MCP Registry verified. It has 4 tools. It can delete or cancel things (1 tool: order_installation) and create or change data (3 tools: check_availability, book_plumber and quote_installation). None of its tools only reads.

2 tools bring in text other people can write (book_plumber and order_installation); 1 tool can send data out of your system (book_plumber).

None of the fixed checks matched anything in its tool definitions. That is not a safety guarantee.

Its remote endpoint lists its tools without sign-in.

Last scanned Nov 7, 2026, version 1.3.0.

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.

4 tools

Deletes or cancels 1Removes, cancels or revokes something.Claude Code: deny

order_installationOrder a fixed-price installation priced by quote_installation, on one of its installation dates.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 destructive (destructiveHint: true).
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
Description, as the server wrote it
Order a fixed-price installation priced by quote_installation, on one of its installation dates. Confirm the chosen option, any extras, the total, the date and the address with the customer before calling this. It sends the customer's name, phone number, email, address and answers about the home to Renzy, and emails the customer their quote. It does not collect or charge a card. The result includes a link for photos of the home. Each call creates a new order, so do not retry a call that succeeded.
Annotations the server declares
- title: Order a boiler or air conditioning installation
- readOnlyHint: false
- destructiveHint: true
- idempotentHint: false
- openWorldHint: true

Changes things 3Creates or changes something that can be changed back.Claude Code: ask

book_plumberBook a Renzy plumber to visit the customer's address in one arrival window.Reads text others writeCan send data outNo findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
What it can reach
- untrusted-inputThe server marks it openWorldHint: true: it reaches things outside the server's own data.
- outboundThe input takes a destination (input.phone): what the tool writes goes there.
Description, as the server wrote it
Book a Renzy plumber to visit the customer's address in one arrival window. Call check_availability first and use a slot_id it returned. Confirm the window, the hourly rate and the address with the customer before calling this. It sends the customer's name, phone number, address and a description of the problem to Renzy, who will phone to confirm the visit. It does not collect or charge a card. Each call creates a new booking, so do not retry a call that succeeded.
Annotations the server declares
- title: Book a plumber
- readOnlyHint: false
- destructiveHint: false
- idempotentHint: false
- openWorldHint: true
check_availabilityCheck whether Renzy Plumbers covers a London postcode and list the bookable arrival windows, with their hourly rates in GBP, for the next N days.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
Check whether Renzy Plumbers covers a London postcode and list the bookable arrival windows, with their hourly rates in GBP, for the next N days. Use this before book_plumber. Read-only: it does not book a visit, contact the customer, or change anything.
Annotations the server declares
- title: Check plumber availability
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false
quote_installationWork out Renzy's fixed, fully fitted price for a new gas boiler or air conditioning in Greater London.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
Work out Renzy's fixed, fully fitted price for a new gas boiler or air conditioning in Greater London. Call it with the product and every answer so far. A postcode is optional: prices don't use it. If you pass one outside Greater London, this returns needs_a_call straight away. While questions remain it returns them with their options, to ask the customer in order. Questions depend on earlier answers, so call it again after each round. Once all are answered it returns each option's itemised price, the extras and the installation dates on offer. If the home can't be priced online it says why and how to reach Renzy. Read-only: it does not place an order or contact the customer.
Annotations the server declares
- title: Quote a boiler or air conditioning installation
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

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 private-data.

Reads private data0: 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.; book_plumber
order_installation
Can send data out1: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.; book_plumber

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

Remote posture

What anyone on the internet sees at the remote endpoint: an anonymous initialize and tools/list, and the public OAuth metadata.

Tools listed without sign-in

Looked at Nov 8, 2026, 06:19 UTC, unchanged since Nov 8, 2026. No credentials were sent and no tool was called. What is looked at.

Reachable: yes
HTTP status of an anonymous initialize: 200
tools/list served without credentials: yes
Tools that change things, listed without credentials: 4
Protocol version: 2025-06-18
WWW-Authenticate on 401: not observed
resource_metadata in WWW-Authenticate: not observed
RFC 9728 protected resource metadata: not observed
Authorization servers: not observed
Legacy HTTP+SSE transport: no
Dynamic client registration: not observed
Client ID metadata documents: not observed

HighThe whole server
The endpoint served tools/list without credentials, and the list has 4 tools that change things (1 destructive, 3 write). Whether a call also works without credentials was not tested: tools are never called.
Matched text
https://renzy.co.uk/api/mcp: tools/list returned 4 tools to an anonymous client, including order_installation (destructive), check_availability (write), book_plumber (write), quote_installation (write)
What this check looks for

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 1.3.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http plumbers https://renzy.co.uk/api/mcp

claude mcp add --transport http plumbers https://renzy.co.uk/api/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": [],
    "ask": [
      "mcp__plumbers__check_availability",
      "mcp__plumbers__book_plumber",
      "mcp__plumbers__quote_installation"
    ],
    "deny": [
      "mcp__plumbers__order_installation"
    ]
  }
}

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 plumbers. Review it before you use it.

Capability tags behind 2 rules

mcp__plumbers__book_plumber untrusted-input, outbound
mcp__plumbers__order_installation untrusted-input

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/uk.co.renzy/plumbers/verify?hash=2958f9fc6349a02f66efb95954fc8678a26951188e746cc3cd536aacad873100" | jq -e '.changed == false'

Pinned hash 2958f9fc6349, from Nov 7, 2026, 18:19 UTC.

Watch

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

https://anlyon.dev/servers/uk.co.renzy/plumbers/changes.xml

An Atom feed. Works in any feed reader or Slack's RSS app.

Badge

[![anlyon.dev](https://anlyon.dev/badge/uk.co.renzy/plumbers.svg)](https://anlyon.dev/servers/uk.co.renzy/plumbers)

Source: MCP Registry. Synced Nov 7, 2026, 18:19 UTC.