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Reverse Geocode a Point in Japan: Municipality Code and Block (GSI)

gsireversegeocoder/reverse-geocode

Reverse geocodes a latitude and longitude in Japan with the reverse geocoder of the Geospatial Information Authority of Japan (GSI): returns the five digit municipality code (JIS code, whose first two digits are the prefecture) and the Japanese name of the block or district, for example 13101 and 丸の内一丁目 for Tokyo Station. The municipality name itself is not included. A point at sea or outside Japan returns an empty result. GSI data, passed through unmodified and served by Eden Engine; not an official GSI product.

activeper callv1

Price

$0.0026 per call

You pay the price shown. If a call turns out to cost more than its quote, you pay the actual price, capped at twice the quote. No monthly minimum. Top-ups start at $0.50.

Data source

Geospatial Information Authority of Japan

Source: Geospatial Information Authority of Japan (GSI) website, https://www.gsi.go.jp/ENGLISH/page_e30286.html. GSI content is offered under the Public Data License (Version 1.0), which requires the source to be cited; the data is passed through unmodified. Served by Eden Engine; not an official GSI product.

Use it

Five steps: search, inspect, learn, run, settle. No per-tool setup; your agent reaches this tool through the meta-tools it already has.

Connect once and your AI can find and run this tool, and any other it needs.

Install itCreate an account
agent
// 1. search: find the tool
omnial_search({ query: "what you need" })

// 2. inspect: price and input schema
omnial_inspect({ tool: "gsireversegeocoder/reverse-geocode" })

// 3. learn: read the usage guide at runtime
omnial_learn({ tool: "gsireversegeocoder/reverse-geocode" })

// 4. run: price the exact call first, then run it
omnial_execute({ tool: "gsireversegeocoder/reverse-geocode", input: { /* see input_schema */ }, dry_run: true })
omnial_execute({ tool: "gsireversegeocoder/reverse-geocode", input: { /* ... */ } })

// 5. settle: the call is charged when it finishes, nothing to do

Not connected yet? Point your MCP client at https://mcp.eden-engine.com/mcp, then copy a config for your client.

Pricing

Every charge this tool can incur.

ChargePrice
Per call
$0.0026
Updated
Oct 21, 2026

Input and output schemas

Input schema
input_schema.json
{
  "type": "object",
  "required": [
    "lat",
    "lon"
  ],
  "properties": {
    "lat": {
      "type": "number",
      "maximum": 90,
      "minimum": -90,
      "description": "Latitude in decimal degrees (WGS 84), for example 35.6812 for Tokyo Station."
    },
    "lon": {
      "type": "number",
      "maximum": 180,
      "minimum": -180,
      "description": "Longitude in decimal degrees (WGS 84), for example 139.7671 for Tokyo Station."
    }
  },
  "additionalProperties": false
}
Output schema
output_schema.json
{
  "type": "object",
  "properties": {
    "results": {
      "type": "object",
      "required": [
        "muniCd",
        "lv01Nm"
      ],
      "properties": {
        "lv01Nm": {
          "type": "string",
          "description": "Japanese name of the block or district, for example 丸の内一丁目."
        },
        "muniCd": {
          "type": "string",
          "description": "Five digit municipality code (JIS X 0402), with its leading zero; the first two digits are the prefecture (13 is Tokyo)."
        }
      },
      "description": "The place under the point.",
      "additionalProperties": true
    }
  },
  "description": "GSI's answer. `results` is absent (the body is empty) when the point is at sea, outside Japan or in no municipality.",
  "additionalProperties": true
}