MCP · ChatGPT
UK property data in ChatGPT
Added as a developer-mode plugin. ChatGPT discovers the sign-in on its own. Once connected, ChatGPT can resolve any UK address, value it, read its sale and listing history, check its planning constraints and name its registered owner, and read the published indices for any area. 94 tools, 51 of them free, one read-only sign-in.
People who do their research in ChatGPT and want values, sale histories, planning constraints and market series they can cite, rather than a model's recollection of them.
https://mcp.marketcode.ai/mcpSteps
How to connect ChatGPT
- 01
Turn on developer mode
Open Settings, then Security and login, and switch Developer mode on.
- 02
Add the plugin
Go to Plugins, choose the plus button, and enter the name MarketCode, a short description and the MCP server URL https://mcp.marketcode.ai/mcp.
MCP server URLhttps://mcp.marketcode.ai/mcp - 03
Sign in when prompted
ChatGPT discovers the MarketCode sign-in automatically. Sign in with your MarketCode account and approve the read-only property scope.
- 04
Add it to a chat
From the tools menu in a conversation, add the MarketCode plugin. Ask with an address, a postcode or an area.
The same steps sit beside the other clients on the MCP page.
Prompts
Things to ask ChatGPT once it is connected
- “Who is the registered proprietor of title TGL123456 and what else do they hold?”
- “Rank the postcode districts in Greater Manchester by turnover over the last twelve months.”
- “What did comparable lots make at auction in SE last year, against your valuation of each?”
ChatGPT accepts no API keys or custom headers for MCP servers. Sign-in is the only path, and the intended one.
The plugin never links to a checkout. When your balance runs out, the response tells you where to top up.
Tools
Tools to try first
Resolve an address to a UPRN
address_resolve()Resolve free-text address to canonical record (UPRN for UK).
Property summary
property_summary()One-call summary of a property: what it is, what building it belongs to,
Full valuation with back-series
valuation_full()Full valuation block for a property: the value and its range, a monthly
House price index series
market_index_series()The published house-price INDEX for one postcode district or local authority: the level per month (base period = 100), the forecast tail flagged, and provenance saying how the index was built.
Planning designations at a location
planning_designations()Every planning designation affecting a location, in one call: conservation
Registered proprietors of a title
ownership_by_title()Registered proprietor(s) for an HMLR title number.
FAQ
Questions about MarketCode in ChatGPT
Do I need an API key?
+
No. MCP clients sign in with your MarketCode account over OAuth and receive a read-only token. API keys are for the REST API; pasting one into an MCP client does nothing useful and puts a secret where it does not belong.
What does it cost?
+
The catalogue shows which tools are currently free. Priced tools charge fixed credits per successful call, the same as over REST, and a new account starts with free credits. Every tool page and the pricing page show the price; a failed call is not charged.
What can a connected assistant do to my account?
+
Read property data and spend credits at the catalogue price. The scope is read-only property data; it cannot see or change your keys, billing or account, and you can revoke the connection in the Hub at any time.
Is MarketCode in the ChatGPT plugin directory?
+
It is submitted for review. Until it is listed you add it as a developer-mode plugin with the steps above, which is the same server the directory listing will point at.
Also
Other clients
We'll connect ChatGPT with you, on a real address.
Thirty minutes. You leave with the connection made and a question answered.