What is property-prices-mcp AGENTS.md?

Project instructions for an MCP server that searches UK HM Land Registry price-paid data, which records property transactions in England and Wales. It also describes postcode lookups and how to run the server.

It is for finding UK property prices by postcode or address, filtering by price, property type, and date, and looking up nearby postcodes.

They explain how to build, start, configure, and call the server so an agent can search property sale records.

How joemclo/property-prices-mcp configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to joemclo/property-prices-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/joemclo/property-prices-mcp/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/joemclo/property-prices-mcp

Made for: Codex, OpenCode.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/joemclo/property-prices-mcp/agents-md/github.svg)](https://agentmods.dev/instructions/joemclo/property-prices-mcp/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/joemclo/property-prices-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/joemclo/property-prices-mcp/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/joemclo/property-prices-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/joemclo/property-prices-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 716 This file is loaded in full into every session.

When invoked 716 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00716	$0.00716
Opus 5	$0.00358	$0.00358
Sonnet 5	$0.00143	$0.00143
Haiku 4.5	$0.00072	$0.00072

Measured 8d ago against content hash dc8e5494fe7a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

property-prices-mcp AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

AGENTS.md · 24 lines

What it actually says

AGENT GUIDE

This project exposes a Model Context Protocol (MCP) server that lets agents search UK HM Land Registry price-paid data.

Prereqs: Node.js >= 20, npm >= 7.
How to run: build with npm run build, then start the MCP server via property-prices-mcp (bin) or node dist/index.js. In development you can run npm run dev to start via ts-node; npm run start runs the compiled server.
MCP config: register a server named property-prices with command: "property-prices-mcp" (or "node", args: ["./dist/index.js"]). Transport is stdio only.
Available tools:
- search-property-prices. Request parameters (all optional unless noted):
  - postcode (string) or both street + city (strings) are required.
  - minPrice, maxPrice (numbers, GBP), propertyType (detached | semi-detached | terraced | flat | other), fromDate, toDate (YYYY-MM-DD), limit (default 10), offset (default 0), sortBy (date | price, default date), sortOrder (asc | desc, default desc).
- lookup-postcodes. Request parameters (all optional unless noted):
  - postcode (string) or both easting + northing (numbers) are required.
  - radiusMeters, limit, includeSelf, adminDistrict filters.
  - Limits: limit max 500, radiusMeters max 200000.
  - Requires a local Code-Point Open DB: npm run setup:postcodes (or npm run fetch:codepo then npm run build:postcodes).
Behavior: street/city are uppercased automatically for the case-sensitive SPARQL endpoint. Filters for price/type are applied after the query. Sorting/pagination happen in-process. Tool returns a JSON payload with properties, total, offset, limit.
Best prompts: ask for a search with clear filters, e.g. “Find up to 5 flats on Carlton Road in London between £300k–£500k sold in 2023, sorted by price descending.”
Limitations: E2E queries hit https://landregistry.data.gov.uk/landregistry/query and require network access; slow or unavailable endpoints will surface as tool errors. Only price-paid data is exposed; no rental info.
CLI: property-prices-mcp runs the server; npm run cli runs the CLI entrypoint in dist/cli.js.
Testing: fast unit tests with npm test / npm run test:unit; live tests with RUN_E2E_TESTS=true npm run test:e2e (needs internet); npm run test:all runs everything; npm run test-mcp runs a manual MCP smoke test.
Typecheck: npm run typecheck.
Lint/format: npm run lint, npm run lint:fix, npm run format, npm run format:check.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago First seen · 24 lines · 716 tokens per session scan A dc8e5494fe7a

Subscribe to this mod's changes

property-prices-mcp AGENTS.md is an instructions file published in the GitHub repository joemclo/property-prices-mcp (2 stars, last pushed 6mo ago), licensed MIT. It adds 716 tokens to every session, about $0.0036 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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