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UR Check

UR Check searches vacancies in UR rental housing in Tokyo and the surrounding Kanto area, checks every area three times a day, and records which rooms are new, relisted or gone. The website and AI assistants, through MCP, use the same conditions and history.

Try the demo
UR Check home: the headline banner, then the counts of saved conditions, open rooms and recent changes
Type
Web app + MCP server (Japanese UI)
Period
Oct 2026
Runs on
AWS Lightsail, Sydney · Docker Compose · Cloudflare Tunnel

About

UR is first come, first served, and a good room can be gone almost as soon as it's listed. The official site has no vacancy alerts, so this does the watching. The real site is run privately, to stay within the policy.

It was built in this order: web, then MCP, then a web service that supports MCP.

What it does

Search
One area at a time, by rent, floor space, layout, walk to a station without a bus, and no ground floor. Up to 50 rooms by monthly cost.
Saved conditions
Save several named conditions, each with several areas and preferred stations per area. Every edit is versioned, and a condition can be paused.
What changed
Every area is checked three times a day. Rooms are tracked as new, relisted or gone, and rooms that came and went between checks are listed too.
AI assistants (MCP)
Sign in with OAuth, then search, read changes and manage conditions in the chat, with rooms shown as cards. Alerts come from a scheduled task in the AI app.
Sharing
An eight-digit code copies a condition to another user. It expires after seven days and can be withdrawn.
Admin screen
Issue, reset and suspend accounts, and register the AI apps that may connect. A new account comes with a message that has the sign-in and AI connection details in it.

Architecture

UR Check — ArchitectureBun · one processWeb appReactClaude / ChatGPTMCP · OAuthHonoREST · MCP · schedulerServicesSearch · tracking · saved searchesPostgreSQLUR web APIREST APIMCPSaved searches · historyScheduled checks
One Bun process serves the web app, the MCP server that Claude and ChatGPT connect to, and the scheduler that checks UR's listings.

How it's built

Server
Bun · Hono · one process for the REST API, the MCP server and the scheduler
Web
React 19 · Vite
Data
PostgreSQL · Drizzle ORM
Auth · MCP
Better Auth (OAuth provider) · MCP TypeScript SDK · MCP Apps · Zod
Infra
Docker · AWS Lightsail, Sydney · Cloudflare Tunnel
Quality
bun test · Biome · TypeScript · GitHub Actions, with a throwaway PostgreSQL
Creating a condition step by step: step 1 of 6 asks for the area, with three wards and cities picked
Open rooms that match the conditions, as cards with a floor plan and the monthly rent
Change history: rooms that are new, relisted or gone, with the condition each one matches
Admin screen for adding an AI app, with the AI app choices and their callback URLs

Earlier projects

UR Check grew out of these two projects.

Archived · Merged into UR Check

UR Manager

A former UR vacancy search and email alert service, now part of UR Check.

Spring Boot · Azure · Terraform
Archived · Merged into UR Check

UR MCP App

A former MCP app for finding UR vacancies in Claude and ChatGPT, now part of UR Check.

TypeScript · MCP · Railway

Not affiliated with UR (Urban Renaissance Agency). Always confirm availability on the official UR site. The screenshots and the demo use made-up rooms.