1gateway Index.json API

openapi: 3.2.0
info:
  title: 1gateway Index.json API
  version: 0.1.1
  description: '1gateway lets AI agents buy the data and APIs they need, one call at a time: no signup, no API key, paid per request with USDC on Base or Solana via x402. Coverage: company and compliance checks (sanctions, KYB, SEC filings, Korean companies), Korean real estate, trade and macro data, onchain and market data, and agent utilities such as document-to-Markdown. Every response names its source. Failed calls are never charged.'
  x-guidance: 'Use this API when an agent needs data as English JSON with pay-per-call access and no signup. Common tasks: Korea apartment sale transactions and district price summaries, Korean public holidays, Korea company KYB (company resolve, profile, NTS business status, DART filings, supplier check), Korean HWP/HWPX to Markdown, web page to Markdown (web read), and document extract (PDF, DOCX, HWP/HWPX or web page to structured JSON). Current coverage is South Korea: apartment sale prices (MOLIT), exports/imports and 10-day export flash (Korea Customs), Bank of Korea statistics (ECOS), weather forecast by lat/lon (KMA), holidays (KASI); more APIs and countries are coming. Base onchain reads: token risk, wallet balances, token info, transaction status. Also: document → Markdown conversion for web pages, PDF, DOCX and Korean HWP/HWPX (price by detected type, decided before payment). Every /v1 endpoint is paid: call it, receive HTTP 402 with PAYMENT-REQUIRED, pay with an x402 client (USDC on Base or Solana, same price) and retry. No charge on failure: settlement happens only on 2xx; 4xx/5xx are never charged. Agent guide: https://1gateway.dev/agents.md. Status: https://1gateway.dev/status. MCP (Streamable HTTP) is available at https://1gateway.dev/mcp: initialize and tools/list are free, tools/call is paid via x402 _meta.'
  contact:
    email: contact@1gateway.dev
servers:
- url: https://1gateway.dev
tags:
- name: Index.json
paths:
  /index.json:
    get:
      summary: Service index, always JSON (free)
      security: []
      responses:
        '200':
          description: OK (free)
          content:
            application/json:
              schema:
                type: object
      tags:
      - Index.json
      operationId: getIndexJson
      x-operation-id-source: derived
x-x402-network: eip155:8453
x-billing-policy: 'No charge on failure: payment is settled only after the endpoint returns a 2xx response. Any 4xx or 5xx (bad input, no data, upstream error, timeout, disabled endpoint) is not settled, so the signed payment is never collected. Input is validated before the 402 wherever possible. Over MCP, a tool result with isError is not settled either.'
x-error-codes:
- status: 400
  codes:
  - bad_request
  - url_not_allowed
  - bad_checksum
  - not_a_contract
  meaning: Invalid or missing parameters, or a URL/domain that is not allowed.
  retry: Fix the input; do not retry as is.
- status: 402
  codes: []
  meaning: Payment required (x402 v2). The PAYMENT-REQUIRED header holds the exact price.
  retry: Pay with an x402 client and retry with PAYMENT-SIGNATURE.
- status: 403
  codes:
  - not_bok_authored
  meaning: Requested table/resource is not served (e.g. statistics not authored by the Bank of Korea).
  retry: Do not retry.
- status: 404
  codes:
  - not_found
  - tx_not_found
  - tx_not_mined
  meaning: No data for the requested period/code yet.
  retry: Try an earlier period or another code.
- status: 413
  codes:
  - too_large
  meaning: Document is larger than this server's conversion cap (checked before payment).
  retry: Send a smaller document.
- status: 415
  codes:
  - unsupported_type
  - type_mismatch
  meaning: Document type not supported or not matching the declared type (before payment).
  retry: Do not retry as is.
- status: 502
  codes:
  - upstream_error
  - upstream_bad_response
  - upstream_http_error
  - rpc_unavailable
  - source_http_error
  meaning: The upstream source (government API, RPC, target site) returned an error or unreadable data.
  retry: Retry after 30-60 s with backoff.
- status: 503
  codes:
  - endpoint_disabled
  - upstream_not_configured
  - payment_not_configured
  meaning: Endpoint temporarily disabled on this server, or its upstream is not configured. No 402 is issued.
  retry: Check /status; retry later.
- status: 504
  codes:
  - upstream_unreachable
  meaning: The upstream source timed out or was unreachable (Korean public data APIs have occasional outages, esp. holidays).
  retry: Retry after 1-5 min with backoff.