Geo-Parity Vat.json API

openapi: 3.2.0
info:
  title: Geo-Parity Vat.json API
  version: 1.0.0
  description: 'Free, key-less JSON APIs behind geo-parity.com: purchasing power parity, fair global salaries, Schengen 90/180 compliance, cross-timezone meetings, contractor economics, freelance rates, tax-residency day counts, country comparison, cloud region latency, and a digital-nomad visa directory. All GET responses are cacheable; errors return { ok:false, code, message, example }. No key is required: anonymous callers get 1,500 requests/month per IP plus a 30/minute burst cap. An optional API key (Authorization: Bearer gp_live_..., created at /account) only raises those ceilings — responses are identical either way, and a key is metered per account rather than per key. Every response carries X-RateLimit-Limit / -Remaining / -Reset (the minute window) and X-Quota-Limit / -Remaining / -Reset (the calendar month, resetting on the 1st UTC); exceeding either returns 429 with Retry-After and code RATE_LIMITED (slow down) or QUOTA_EXCEEDED (allowance spent — retrying will not help). Figures are informational estimates, not financial/tax/legal advice. Machine discovery: /llms.txt and /.well-known/mcp.json; the same tools are also registered with the browser''s WebMCP ModelContext on every page, executing through /api/mcp.'
  contact:
    url: https://geo-parity.com
servers:
- url: https://geo-parity.com
security:
- {}
- bearerAuth: []
- apiKeyQuery: []
tags:
- name: Vat.json
paths:
  /api/vat.json:
    get:
      operationId: compareVat
      summary: VAT/GST rates with the authority page each was read from, side by side or ranked
      description: Hand-curated standard and reduced VAT/GST rates for the 41-country spine, each with its tax-authority source URL and check date. `countries` compares; otherwise standard rates are ranked lowest first. Countries with no single national rate (US, BR, MY) are excluded from the ranking and named, never given 0%. Not tax advice, and every response says so first.
      parameters:
      - name: countries
        in: query
        schema:
          type: string
        description: Comma-separated ISO alpha-2 codes, two or more
      - name: sort
        in: query
        schema:
          type: string
          enum:
          - lowest
          - highest
        description: Ranking direction (default lowest)
      - name: limit
        in: query
        schema:
          type: number
          minimum: 1
        description: Maximum countries in a ranking
      responses:
        '200':
          description: Rows carrying `source` and `checkedOn`, or a ranking with `excluded`; attribution names the curated set
        '400':
          description: Fewer than two countries (TOO_FEW)
        '422':
          description: A country outside the spine (UNKNOWN_COUNTRY)
      tags:
      - Vat.json
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: Optional Geo-Parity API key (gp_live_...), created at /account. Raises the monthly quota and per-minute burst; never changes a response. Metered per account, so extra keys do not add allowance.
    apiKeyQuery:
      type: apiKey
      in: query
      name: key
      description: The same key, for clients that cannot set headers.
externalDocs:
  description: 'Developer guide: quota ladder, error codes, API keys and MCP setup'
  url: https://geo-parity.com/developers/