Search Japanese Property From Your AI Assistant

The short answer

Engawa now runs an MCP server, so you can search the Japanese property catalogue from inside Claude or any other MCP-compatible AI client, in conversation, without opening the website.

Ask for as-is farmhouses in Chiba under ¥5,000,000 with more than 300 m² of land, and your assistant filters the catalogue directly, pulls the full record on anything promising, compares candidates side by side, and runs Japanese closing costs on the shortlist.

It is included with annual Explorer membership, and you connect it with an API key from your account page.

What it actually does

MCP, the Model Context Protocol, is an open standard for giving an AI assistant access to a real data source rather than to its own recollection of one. Engawa's server exposes six tools:

The practical difference from browsing is not speed. It is that the search becomes a conversation with follow-ups. You can say "of those, which are pre-1981 construction, and what would each cost to close?" and get an answer built from the same query layer the website runs on, rather than from a model's impression of Japanese property.

The part we spent the most time on

Here is the design problem, and it is not the one you would expect.

A language model handed a property record will answer whatever it is asked. If a field is missing, it does not stop. It infers. Give it a house 137 metres from a station and no timetable, and it will tell someone the commute is reasonable, because "137 metres from a station" sounds like it settles the question. It does not settle anything: 137 metres is a ruler measurement on a map, and the station might see four trains a day.

So the guiding rule across the whole tool surface is that an unknown is stated in words, in the payload, never left as a missing field. A missing field reads as "no such number exists." A stated unknown reads as a question the buyer still has to ask.

Some examples of what that looks like in practice.

The same applies to condition. No listing in the catalogue carries a survey, a seismic diagnosis or a defect disclosure, so compare_properties explicitly refuses to rank two as-is buildings by how much work they need, however different their photographs look. One might need a roof and the other a foundation, and nothing in the data tells them apart.

What it does tell you that the listing page does not

Two things worth calling out, because they are derived rather than scraped.

Seismic standard. Japan revised its building code for permits issued from 1 June 1981, and the gap between the old standard (kyu-taishin) and the new one (shin-taishin) is not cosmetic. It drives collapse risk in a large quake, how insurers price the building, whether a lender will touch it, and whether the earthquake-resistance tax reductions apply. A second revision in June 2000 tightened timber-frame requirements specifically: foundations, hold-down hardware, and the balance of load-bearing walls.

Every search result carries its seismic label, so a shortlist can be filtered on the 1981 cutoff without opening each listing. A house built exactly in 1981 is reported as undetermined rather than resolved either way, because the standard keys off the permit date and a catalogue holds only a year.

Regional distance. Straight-line distance to the two nearest regional employment centres, given as distance and labelled as distance. Two rather than one, deliberately: the nearest by ruler is regularly not the relevant one. A house in Isumi is marginally closer to Yokohama than to Tokyo, while the line running through it goes to Tokyo. We do not convert either figure into a commute time, because 40 km in Japan is 35 minutes on a shinkansen or two hours with three changes, and dividing distance by an assumed speed would be a fabricated commute presented as a fact.

Connecting it

1. 1

   Hold an annual Explorer membership.The AI catalogue is included with annual plans at $99 a year. Monthly plans do not carry it, and you can switch at any time from the pricing page.

2. 2

   Create an API key.From your account page. Name it after the device it will live on, so you can revoke the right one later. The key is shown once and stored only as a hash.

3. 3

   Paste the configuration into your client.The account page generates a ready-made JSON snippet for Claude Desktop, Claude Code, or any MCP client that speaks HTTP transport.

4. 4

   Restart the client.The Engawa tools appear in your client's tool list. Ask it something.

The endpoint is https://engawahomes.com/api/mcp, authenticated with a bearer token. Keys are per-device and individually revocable, so losing a laptop costs you one key rather than your account.

What it is not

Engawa is not a licensed broker, and the AI catalogue does not change that. It relays listing facts as sourced claims, links you to the listing page, and does not present any figure as advice or as independently verified. Listing data comes from the cited source. Confirm every figure with the agent before acting on it.

It also will not contact anyone on your behalf, collect your details, or handle any part of a transaction. When a search turns into a serious shortlist, that is the point at which a licensed local agent becomes necessary, and the concierge service exists for exactly that handover.

Annual membership only

To be unambiguous about it: the AI catalogue is included with annual Explorer, and monthly Explorer does not carry it.

The distinction is enforced at the tool call rather than at the connection. A monthly member can create an API key and connect a client successfully, and the tools will appear in their client's list, but calling one returns an upgrade notice instead of listings. That is deliberate. Refusing the connection outright surfaces in most clients as "server failed to connect", which reads as a bug rather than as an offer.

Switching from monthly to annual takes effect immediately, from the pricing page.

Sources and review notes

Transit and hazard context is derived from open government and OpenStreetMap data, and is present only where a lookup resolved. Seismic standard is derived from the recorded build year alone and is an indication, not a certification: only the permit date on the register settles it. Nothing here is legal, tax, structural or investment advice.

• Model Context Protocol: specification and client list
• MLIT: building standards and seismic retrofit guidance
• OpenStreetMap: station data and ODbL licence terms
• GSI Hazard Map Portal: the official hazard source

Editorial ownerEngawa Editorial Team

MethodProduct documentation and code review of the shipped tool surface

Checked on5 August 2026

This article is general information, not personalized legal, tax, structural, financing, visa, or investment advice. Property and service availability can change.

Frequently asked questions

What is Engawa's MCP server?+

It is an implementation of the Model Context Protocol, an open standard that lets an AI assistant query a live data source directly. Engawa's server exposes six tools: search_properties, get_property, compare_properties, estimate_closing_costs, list_prefectures and concierge_info. Connected to Claude or any other MCP client, it lets you filter the Japanese property catalogue, pull full listing records, compare candidates and estimate closing costs in conversation, using the same query layer the website runs on.

Do I need an annual membership to use the AI catalogue?+

Yes. The AI catalogue is included with annual Explorer membership at $99 a year, and monthly Explorer does not carry it. A monthly member can sign in, create an API key and connect a client successfully, but calling a catalogue tool returns an upgrade notice rather than listings. Switching from monthly to annual takes effect immediately.

How do I connect Engawa to Claude?+

Create an API key from your Engawa account page, which generates a ready-made JSON configuration snippet. Paste it into your MCP client's configuration and restart the client. The endpoint is https://engawahomes.com/api/mcp, authenticated with a bearer token. Keys are per-device and individually revocable, and each key is shown once at creation and stored only as a hash.

Can the AI tell me how long the commute is from a listing?+

No, and it will say so rather than estimate. Engawa holds no timetable data, so service frequency, whether express services stop at a station, and rail journey time to any city are all unavailable. What is provided is straight-line distance to the nearest station and to the two nearest regional centres, labelled explicitly as map distance. Converting that into a commute time would mean dividing distance by an assumed speed, which in Japan can be wrong by a factor of three over the same distance.

Does the catalogue include the municipal assessed value?+

No. The assessed value (kotei shisan zei hyoka gaku) is not published with a sale and appears only on the tax certificate (hyoka shomeisho) held by the seller or the municipal tax office. This matters because Japanese purchase taxes are levied on the assessment rather than on the asking price, and on cheap rural property the two can diverge by several times. The closing-cost tool derives a rough default from the price when no assessment is supplied and states clearly that the result is an order of magnitude, not a figure. Asking the agent for the certificate is the single step that turns the estimate into a number.

Can the AI tell me what condition a house is in?+

Only what the seller labelled it. Engawa holds no inspection, no seismic diagnosis and no defect disclosure for any listing, so two as-is buildings cannot be ranked by how much work they need, however different their photographs look. The comparison tool refuses to rank them on that basis. A building inspection (jutaku shindan, typically 50,000 to 100,000 yen) and, on a pre-1981 building, a seismic diagnosis are what settle it.

What is the 1981 seismic standard and why is it in the search results?+

Japan revised its building code for permits issued from 1 June 1981. Buildings meeting the newer specification are called shin-taishin; older ones kyu-taishin. The difference drives collapse risk in a large earthquake, how insurers price the building, whether lenders will finance it, and whether earthquake-resistance tax reductions apply. A further revision in June 2000 tightened timber-frame requirements. Every search result carries a seismic label so a shortlist can be filtered on that cutoff without opening each listing. A house built in 1981 itself is reported as undetermined, because the standard keys off the permit date while the catalogue records only a year.

Is the AI catalogue a substitute for an agent?+

No. Engawa aggregates listings and refers buyers to licensed local agents. It is not a licensed broker, does not handle contracts or legal steps, and the AI tools relay listing facts as sourced claims rather than as verified figures or advice. The tools will not contact anyone on your behalf or handle any part of a transaction. Confirm every figure with the responsible agent before acting on it.