# jp-real-estate

> What real estate transaction prices has MLIT published for this Japanese municipality? Hosted MCP and HTTP: no install. Per municipality (5-digit code) and quarter, the published samples from MLIT's Real Estate Information Library, transaction and contract prices kept separate: counts and min/median/max computed by us (withheld below 5 values), a capped sample of records as published, and a source and freshness receipt. Free. Published statistics as released; not a valuation and not advice.

Data source: Ministry of Land, Infrastructure, Transport and Tourism of Japan (MLIT), Real Estate Information Library (Fudosan Joho Library), https://www.reinfolib.mlit.go.jp/ (API manual: https://www.reinfolib.mlit.go.jp/help/apiManual/xit001/ and https://www.reinfolib.mlit.go.jp/help/apiManual/xit002/; API terms: https://www.reinfolib.mlit.go.jp/help/termsOfUse/). Required credit (MLIT API terms, Article 7): このサービスは、国土交通省の不動産情報ライブラリのAPI機能を使用していますが、提供情報の最新性、正確性、完全性等が保証されたものではありません (English: This service uses the API of the Real Estate Information Library of the Ministry of Land, Infrastructure, Transport and Tourism of Japan (MLIT), but the recency, accuracy and completeness of the information provided are not guaranteed. (Translation by MK Career Planning; the Japanese text is the required credit.)) Counts and the minimum, median and maximum are computed by MK Career Planning from the records published by MLIT (processed data). They were not produced by MLIT or the Government of Japan, and they are not an appraisal or a valuation of any property. Processed by MK Career Planning; not an official service of MLIT or the Government of Japan.
Statistics as published by MLIT, relayed with simple counts and order statistics computed from the published records. Not an appraisal or a valuation of any property, and not advice on buying, selling, lending, tax or law. Not an official service of MLIT or the Government of Japan.
Statuses per quarter: records_published (MLIT answered and published records match the query), no_records_published (MLIT answered normally for a published quarter and no matching records were in it), unknown with unknown_reason: not_fetched_yet, upstream_error, quarter_not_yet_published, api_key_missing or outside_source_coverage. An upstream failure is never reported as no records.
count, min, median and max are computed by MK Career Planning from the published TradePrice (total price, JPY) and UnitPrice (price per square meter, JPY; published mainly for land) of the records in the quarter, separately for transaction prices and contract prices. Records without a numeric published value are left out of that statistic (n says how many were used). The median of an even number of values is the mean of the two middle values. When fewer than 5 values are available, only n is returned and min, median and max are null with suppressed_reason small_sample_suppressed, because the extremes of a few anonymised records can point to a specific deal. Each quarter is a set of published samples (for example 2025-Q1 published samples), not every deal made in that quarter, and MLIT may add records later. The median is not the price any particular property would sell for, not an appraisal or a valuation of any property, and not the current price level.
Transaction prices (MLIT 不動産取引価格情報, compiled from survey responses) and contract prices (MLIT 成約価格情報, anonymised REINS data) are counted and summarised separately and never pooled. MLIT's terms say the same deal may appear in both datasets, so do not add the two counts together as a number of deals.
Join keys: 5-digit municipality code and 2-digit prefecture code, the same as other Japanese public data. At most 8 quarters per request; answers are fetched from MLIT on demand per municipality and quarter and cached (past quarters up to 30 days, recent quarters 1 day). This service caps its own calls to MLIT, so a large request may return some quarters as unknown (not_fetched_yet): ask again for those.

## Connect

- MCP (streamable HTTP): https://jp-real-estate-production.mk-career-planning.workers.dev/mcp
- OpenAPI: https://jp-real-estate-production.mk-career-planning.workers.dev/openapi.json
- x402 discovery: https://jp-real-estate-production.mk-career-planning.workers.dev/.well-known/x402

## Quickstart

- Developer quickstart (MCP client configs, free curl/TypeScript calls, how to read status, unknown_reason, the computed statistics and the required MLIT credit): https://jp-real-estate-production.mk-career-planning.workers.dev/quickstart

## Free tools

- catalog: List the tools of this server with prices, data sources, licensing, daily limits and data freshness.
- realestate_prices_by_municipality: What real estate transaction and contract prices has MLIT (Japan) published for this municipality and quarter? Give a 5-digit municipality code and up to 8 quarters (YYYY-Qn). Per quarter and per classification (never pooled): records_published, no_records_published or unknown with a reason, record counts, min/median/max computed by us (null below 5 values), and a capped sample of records as published. Carries the required MLIT credit. Statistics as published; not an appraisal or advice.
- realestate_municipalities: Which municipality codes and names does MLIT's Real Estate Information Library list for this Japanese prefecture? Give a prefecture code (01-47) or name. Returns the 5-digit municipality codes with Japanese and English names as published by MLIT (XIT002): the join key for realestate_prices_by_municipality and other Japanese public data. Carries the required MLIT credit.
- get_receipt: Re-fetch the stored result of a settled paid call by its receipt_id, for when the response was lost after payment. Free. Unknown or unsettled receipt ids return RECEIPT_NOT_FOUND. Results are kept for 90 days after settlement.
- HTTP: GET https://jp-real-estate-production.mk-career-planning.workers.dev/v1/real-estate/prices, GET https://jp-real-estate-production.mk-career-planning.workers.dev/v1/real-estate/municipalities return the same data as the MCP tools. GET https://jp-real-estate-production.mk-career-planning.workers.dev/v1/receipts/<receipt_id> is get_receipt.

## Payments

This server offers free tools only. It does not request or accept x402 payments.

## Rate limits

- Free calls (free HTTP endpoints under /v1/ and free MCP tools) are limited to 300 requests per 60 seconds per client (a client is keyed by a one-way hash of its IP address and the first 64 characters of its User-Agent; neither is stored. The User-Agent can be set by anyone, so this split is for fairness between clients behind a shared gateway, not a security control). Over the limit, HTTP returns 429 RATE_LIMITED with a Retry-After header and MCP tools return the error RATE_LIMITED. Paid calls are not rate limited.

## Provenance and fetch_status

Responses carry provenance[] (source, upstream_updated_at, retrieved_at, content_sha256, parser_version, fetch_status). fetch_status values:

- found: The upstream document was retrieved and contains the data used for this answer.
- empty: The upstream was retrieved, but it has no item for this query (for example JMA had no bulletin for that area in its feeds, or the municipality is not in the list). The state is unknown: empty does NOT mean 'none in effect'.
- stale: The data was retrieved but is older than the freshness threshold for its kind; treat it with care.
- unavailable: The upstream could not be retrieved, read or used (network error, withdrawn bulletin, paused source, or data not yet loaded).
- unsupported: The query is outside what this source covers (for example a date JMA does not issue warnings for yet, or a period before the source's records).

## Errors

- RECEIPT_NOT_FOUND (get_receipt)
- RATE_LIMITED (free calls over the per-client limit; HTTP 429 with Retry-After; not charged)

## Terms

- Keep the attribution (credit_ja, the processing statement and the source URL) when you pass results on, and do not present the computed figures as produced by MLIT.
- Statistics as published; not an appraisal or a valuation of any property, and not advice on buying, selling, lending, tax or law.

## Privacy and support

- Operator: MK Career Planning
- Terms of Service: https://jp-real-estate-production.mk-career-planning.workers.dev/terms
- Privacy policy: https://jp-real-estate-production.mk-career-planning.workers.dev/privacy
- Support (free): https://jp-real-estate-production.mk-career-planning.workers.dev/support (mk.career.planning@gmail.com)