openapi: 3.2.0
info:
  title: AAAA Nexus Credits API
  version: 0.5.1
  description: Formally verified AI safety APIs for autonomous agents. Supports REST, MCP, A2A (Google protocol), and x402 micropayment protocol.
  contact:
    email: atomadic69@gmail.com
    url: https://github.com/atomadictech/aaaa-nexus
servers:
- url: https://atomadic.tech
  description: Production
security: []
tags:
- name: Credits
  description: Credit balance, usage history, and detailed usage breakdown
paths:
  /v1/credits/balance:
    get:
      operationId: getCreditBalance
      summary: Check credit balance
      description: Check the remaining credit balance for the API key.
      tags:
      - Credits
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: Credit balance
          content:
            application/json:
              schema:
                type: object
                properties:
                  balance:
                    type: number
                  currency:
                    type: string
                    example: USD
                  last_charged:
                    type: string
                    format: date-time
        '401':
          $ref: '#/components/responses/Unauthorized'
  /v1/credits/history:
    get:
      operationId: getCreditHistory
      summary: Credit usage history
      description: Retrieve credit usage history for the API key.
      tags:
      - Credits
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: Credit history
          content:
            application/json:
              schema:
                type: object
                properties:
                  transactions:
                    type: array
                    items:
                      type: object
                      properties:
                        endpoint:
                          type: string
                        amount:
                          type: number
                        timestamp:
                          type: string
                          format: date-time
        '401':
          $ref: '#/components/responses/Unauthorized'
  /v1/credits/usage:
    get:
      operationId: getCreditUsage
      summary: Detailed usage breakdown
      description: Get a detailed breakdown of credit usage by endpoint and time period.
      tags:
      - Credits
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: Usage breakdown
          content:
            application/json:
              schema:
                type: object
                properties:
                  period:
                    type: string
                  total_spent:
                    type: number
                  by_endpoint:
                    type: object
                  by_day:
                    type: array
                    items:
                      type: object
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  responses:
    Unauthorized:
      description: Missing or invalid API key.
      content:
        application/json:
          schema:
            type: object
            properties:
              error:
                type: string
                example: Unauthorized
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: API key obtained from https://atomadic.tech/pay
    X402PaymentProof:
      type: apiKey
      in: header
      name: X-Payment-Proof
      description: Base64-encoded USDC payment proof for x402 autonomous payment flow (Base L2, Polygon, or Solana)
    AdminTokenAuth:
      type: apiKey
      in: header
      name: X-Admin-Token
      description: Admin token for privileged operations