# Kaisha API – Japanese Corporate Number Resolver

> Kaisha API – Japanese Corporate Number Resolver is a paid API for AI agents from kaisha-api.hp-vladic.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Resolves a Japanese company name or 13-digit corporate number to its official NTA registry record, including corporate number, canonical name, head-office address, entity type, and active/closed status.

## Facts

- Endpoint: GET https://kaisha-api.hp-vladic.workers.dev/resolve
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/kaisha-api-japanese-corporate-number-resolver-3c5853aa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_rLu8HejWbHcuUyXhBv3K4

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability kaisha-api-japanese-corporate-number-resolver-3c5853aa
```

Example prompt: Can you look up the official NTA registry record for トヨタ自動車株式会社 — I need their 13-digit corporate number, registered head-office address, and whether they're currently active?

## When to prefer this

Use this endpoint when you need to authoritatively resolve a Japanese company to its official NTA registry identity — corporate number, canonical name, address, and status — especially when you have only a colloquial or partial name and need fuzzy normalization across kana/kanji variants. Prefer over general web search when you need structured, authoritative registry data on any of Japan's ~5M registered corporations.

## Known failure modes

- Company name not found in registry — returns empty results or 404
- Ambiguous name matches too many records — returns up to limit results, may need refinement
- Invalid or non-existent 13-digit corporate number — returns no match
- Non-Japanese company queried — not in NTA registry, no results
- Malformed query parameter — 400 bad request
- Payment not fulfilled — 402 payment required (x402 protocol)

## How this service works

Resolve a Japanese company to its official registry record: 13-digit corporate number (法人番号), canonical registered name, head-office address, entity type, and active/closed status. Query by name (fuzzy normalization: legal-form words, zenkaku/hankaku and kana variants are handled) or by corporate number. Source: National Tax Agency corporate number registry, all ~5M registered corporations in Japan.

## Output

Returns up to 25 matching registry records from the NTA's ~5M Japanese corporations, each including the 13-digit corporate number (法人番号), canonical registered name, head-office address, legal entity type, and active/closed status. Fuzzy normalization handles zenkaku/hankaku, kana variants, and legal-form suffixes.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Company name (Japanese) or 13-digit corporate number"
      },
      "limit": {
       "type": "number",
       "description": "Max results (default 10, max 25)"
      },
      "prefecture": {
       "type": "string",
       "description": "Optional prefecture filter (e.g. 東京都)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "found": 1,
  "query": {
   "type": "name",
   "value": "トヨタ自動車",
   "normalized": "トヨタ自動車",
   "prefecture": "愛知県"
  },
  "results": [
   {
    "kind": {
     "en": "Kabushiki Kaisha (stock company)",
     "ja": "株式会社"
    },
    "name": "トヨタ自動車株式会社",
    "status": "active",
    "address": {
     "city": "豊田市",
     "street": "トヨタ町1番地",
     "postCode": "4718571",
     "prefecture": "愛知県"
    },
    "closeDate": null,
    "lastUpdate": "2026-06-30",
    "corporateNumber": "1180301018771"
   }
  ],
  "matchType": "exact"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/kaisha-api-japanese-corporate-number-resolver-3c5853aa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kaisha-api.hp-vladic.workers.dev](https://www.zero.xyz/host/kaisha-api.hp-vladic.workers.dev/llms.txt)