fourzerotwo-si

fourzerotwo-si Federal Register API

US Federal Register: US federal rules, proposed rules, notices and presidential documents: search and detail.

GitHub OpenAPI

Operations 4

GET /v1/federal-register/search US Federal Register: Search documents #
GET /v1/federal-register/document US Federal Register: Document #
GET /v1/federal-register/public-inspection US Federal Register: Public inspection today #
GET /v1/federal-register/agencies US Federal Register: Agencies #

Specifications

⚙
OpenAPI
https://artifacts.apis.io/fourzerotwo-si/openapi/fourzerotwo-si-federal-register-api-openapi.yml

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OpenAPI Specification

fourzerotwo-si-federal-register-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Fourzerotwo Si Federal Register API
  version: 1.1.0
  contact:
    url: https://fourzerotwo.si
  description: 'Operations tagged federal-register across 2 of this provider''s published API definitions: openapi.json, fourzerotwo-si-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://fourzerotwo.si
tags:
- name: federal-register
  description: 'US Federal Register: US federal rules, proposed rules, notices and presidential documents: search and detail.'
paths:
  /v1/federal-register/search:
    get:
      operationId: federal_register__search
      summary: 'US Federal Register: Search documents'
      description: 'Rules, proposed rules, notices and presidential documents matching a term. Price: $0.003 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - federal-register
      externalDocs:
        url: https://fourzerotwo.si/apis/federal-register/search
      parameters:
      - name: q
        in: query
        required: true
        description: Search term
        schema:
          type: string
        example: artificial intelligence
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.003000'
      x-free-tier: free
      x-mcp-tool: federal-register__search
    servers:
    - url: https://fourzerotwo.si
  /v1/federal-register/document:
    get:
      operationId: federal_register__document
      summary: 'US Federal Register: Document'
      description: 'One Federal Register document by document number. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - federal-register
      externalDocs:
        url: https://fourzerotwo.si/apis/federal-register/document
      parameters:
      - name: number
        in: query
        required: true
        description: Document number
        schema:
          type: string
        example: 2025-02172
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: free
      x-mcp-tool: federal-register__document
    servers:
    - url: https://fourzerotwo.si
  /v1/federal-register/public-inspection:
    get:
      operationId: federal_register__public_inspection
      summary: 'US Federal Register: Public inspection today'
      description: 'Documents on public inspection ahead of publication. Price: $0.002 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - federal-register
      externalDocs:
        url: https://fourzerotwo.si/apis/federal-register/public-inspection
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.002000'
      x-free-tier: free
      x-mcp-tool: federal-register__public-inspection
    servers:
    - url: https://fourzerotwo.si
  /v1/federal-register/agencies:
    get:
      operationId: federal_register__agencies
      summary: 'US Federal Register: Agencies'
      description: 'Every federal agency that publishes in the Register. Price: $0.001 USDC per call via x402. Free within the daily allowance with a free key.'
      tags:
      - federal-register
      externalDocs:
        url: https://fourzerotwo.si/apis/federal-register/agencies
      responses:
        '200':
          description: The data (paid, or free tier).
          content:
            application/json: {}
        '402':
          $ref: '#/components/responses/PaymentRequired'
        '400':
          $ref: '#/components/responses/Error'
        '404':
          $ref: '#/components/responses/Error'
        '502':
          $ref: '#/components/responses/Error'
      security:
      - {}
      - freeKey: []
      x-price-usd: '0.001000'
      x-free-tier: free
      x-mcp-tool: federal-register__agencies
    servers:
    - url: https://fourzerotwo.si
components:
  responses:
    PaymentRequired:
      description: x402 payment required. The body (also base64 in the PAYMENT-REQUIRED header) lists accepted payments.
      headers:
        PAYMENT-REQUIRED:
          schema:
            type: string
          description: Base64 JSON x402 v2 PaymentRequired
      content:
        application/json:
          schema:
            type: object
            properties:
              x402Version:
                type: integer
              error:
                type: string
              accepts:
                type: array
                items:
                  type: object
    Error:
      description: 400 = invalid input, 404 = not found at the source, 502 = the source failed. Never charged.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
              charged:
                type: boolean
  securitySchemes:
    freeKey:
      type: apiKey
      in: header
      name: X-API-Key
      description: Optional free key (fzt_…) for the free tier.
x-refined-from:
- openapi.json
- fourzerotwo-si-openapi.json