@kessan/sdk — TypeScript SDK

Official TypeScript / JavaScript SDK for the Kessan API — Japanese financial disclosures for AI agents.

English-first, type-safe access to Japanese listed company financial disclosures, designed for AI agents and systematic researchers.

Install

npm install @kessan/sdk
# or
pnpm add @kessan/sdk
# or
bun add @kessan/sdk

Coming soon. Target: 2026-08-15

Quick start

import { Client } from '@kessan/sdk';

const client = new Client({ apiKey: process.env.KESSAN_API_KEY });

// 10 years of quarterly P&L for Toyota — English schema, Q4 differential
const financials = await client.companies.getFinancials('7203', {
  years: 10,
  quarterly: true,
  normalizeCurrency: 'JPY',
});

for (const row of financials) {
  console.log(row.fiscalPeriod, row.revenue, row.operatingIncome);
}

Features

• Full TypeScript types, zero any
• Works in Node 18+, Deno, Bun, edge runtimes (Cloudflare Workers, Vercel Edge)
• Automatic retry + rate limit handling
• LLM-friendly responses (works directly with Anthropic / OpenAI tool-use)
• Provenance per data point

License

MIT — see LICENSE.

Repository scope

This repository only contains:

• HTTP client wrapper
• TypeScript type definitions
• Auth / retry / rate-limit helpers
• Error code definitions
• Usage examples

It does NOT contain:

• XBRL parsing logic
• Data normalization logic
• Business rules
• EDINET-specific knowledge

All business logic lives in /JDI/backend/ (proprietary, never published).

Links

• API Documentation
• Cookbook examples
• Issue tracker