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OpenAPI Specification

openapi: 3.2.0
info:
  title: emission-factors.com MCP API
  version: 2.1.0
  description: 'US electricity and fuel emission data by ZIP code: EPA eGRID Scope 2 factors (location-based) with the Green-e residual mix (market-based), Scope 1 fuel factors, EIA retail rates and hourly grid intensity, EPA CAMD plant emissions and OpenEI utility tariffs. Free, no key. Query parameters and JSON body fields not listed here are rejected with 400.'
  contact:
    url: https://emission-factors.com
  license:
    name: 'Data licenses vary by source: US government works (public domain); eGRID2024, GHG Hub 2026, OpenEI URDB and ZIP-to-utility data, and GeoNames are CC-BY-4.0; the Green-e residual mix is published by the Center for Resource Solutions. See /methodology.'
    url: https://emission-factors.com/methodology
servers:
- url: https://emission-factors.com
  description: Production
tags:
- name: MCP
paths:
  /mcp:
    post:
      summary: 'MCP server (JSON-RPC 2.0 over Streamable HTTP, stateless, keyless): initialize…'
      operationId: mcp
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - jsonrpc
              - method
              properties:
                jsonrpc:
                  type: string
                  example: '2.0'
                id:
                  type: integer
                  example: 1
                method:
                  type: string
                  example: tools/list
                params:
                  type: object
      responses:
        '200':
          description: JSON-RPC response
        '204':
          description: Notification accepted
      tags:
      - MCP