generated: '2026-09-16'
method: derived
source: >-
  Derived by binding the four @unirate/mcp tools (from unirate-mcp README) to their backing
  OpenAPI operationIds in openapi/unirateapi-openapi.yaml. Confidence high — the tool
  names/params map cleanly onto the documented GET operations.
surfaces:
  openapi: openapi/unirateapi-openapi.yaml
  mcp: 'npx -y @unirate/mcp (local-stdio; no hosted endpoint)'
  gated:
  - The MCP server calls UniRate with the operator's UNIRATE_API_KEY; historical_rate is Pro-gated.
crosswalk:
- tool: convert
  category: conversion
  rest: [convert]
  binding: direct
  confidence: high
  note: MCP requires `to`; inherits from/to/amount from the OpenAPI convert operation.
- tool: latest_rate
  category: rates
  rest: [getRates]
  binding: direct
  confidence: high
  note: Omitting `to` returns the full rates map, matching getRates behavior.
- tool: historical_rate
  category: historical
  rest: [getHistoricalRates]
  binding: direct
  confidence: high
  note: Pro-gated on both surfaces (HTTP 403 free tier).
- tool: list_currencies
  category: currencies
  rest: [getCurrencies]
  binding: direct
  confidence: high
mcp_only: []
rest_only:
- operationId: getVatRates
  reason: No MCP tool exposes country VAT rates.
- operationId: getTimeSeries
  reason: No MCP tool exposes historical time series.
- operationId: getHistoricalLimits
  reason: No MCP tool exposes historical coverage limits.
coverage:
  mcp_tools: 4
  mapped_to_rest: 4
  mcp_only: 0
  rest_only: 3
  openapi_operations: 8