> ## Documentation Index
> Fetch the complete documentation index at: https://agora402.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# A2A agent card

> An A2A-compatible agent card so generic A2A tooling can find the seller. The x402 extension is marked required and carries the payment network, the facilitator URL and the accepted asset symbols; a second, optional extension points at the full Agora402 manifest. Skills mirror the manifest endpoints. Free, unauthenticated.



## OpenAPI

````yaml /openapi.yaml get /.well-known/agent.json
openapi: 3.1.0
info:
  title: Agora402 seller API
  version: 1.0.0
  description: >-
    HTTP API served by every Agora402 seller: free discovery documents, a free
    quote endpoint, and paid endpoints gated by x402 and settled on Hedera
    through the Blocky402 facilitator. Typical agent flow: getManifest (what is
    sold, at what price, paid to which account) -> requestQuote (lock a signed
    price, counter below list if you like) -> call the paid endpoint with the
    quoteId. The first call answers 402 with a PAYMENT-REQUIRED header; the
    retry carries PAYMENT-SIGNATURE; the response carries PAYMENT-RESPONSE with
    the Hedera transaction id. Then read listReceipts or the seller's HCS
    receipts topic to audit what was charged. All amounts are decimal strings in
    atomic units of the asset (tinybars for HBAR, 8 decimals); timestamps are
    ISO 8601 unless stated; quote expiry is unix seconds.
servers:
  - url: http://localhost:4402
    description: Local services seller (npm run dev)
  - url: http://localhost:4404
    description: Local auditor (npm run dev)
security: []
tags:
  - name: Discovery
    description: Free documents that describe the seller. Read these before paying anyone.
  - name: Negotiation
    description: Free, signed, time-limited price quotes.
  - name: Paid services
    description: x402-gated endpoints. Every call is a Hedera micropayment.
  - name: Trust
    description: Paid audits of other sellers, attested on the HCS audit topic.
  - name: Receipts
    description: What this seller has been paid for.
paths:
  /.well-known/agent.json:
    get:
      tags:
        - Discovery
      summary: A2A agent card
      description: >-
        An A2A-compatible agent card so generic A2A tooling can find the seller.
        The x402 extension is marked required and carries the payment network,
        the facilitator URL and the accepted asset symbols; a second, optional
        extension points at the full Agora402 manifest. Skills mirror the
        manifest endpoints. Free, unauthenticated.
      operationId: getAgentCard
      responses:
        '200':
          description: Agent card
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/AgentCard'
              example:
                name: agora-demo-seller
                description: >-
                  Agora402 seller: pay-per-request AI and data services on
                  Hedera over x402.
                url: http://localhost:4402
                version: 1.0.0
                provider:
                  organization: Agora402
                  url: https://github.com/ddpateltp/agora402
                uaid: >-
                  uaid:aid:2NEpo7TZRRrLZSi2U;uid=agora-demo-seller;registry=agora402;proto=a2a;nativeId=hedera:testnet:0.0.5001234;domain=localhost:4402
                capabilities:
                  streaming: false
                  pushNotifications: false
                  extensions:
                    - uri: >-
                        https://github.com/a2aproject/A2A/blob/main/docs/extensions/x402.md
                      description: x402 micropayments settled on Hedera via Blocky402
                      required: true
                      params:
                        payment_network: hedera:testnet
                        facilitator: https://api.testnet.blocky402.com
                        assets:
                          - HBAR
                    - uri: http://localhost:4402/.well-known/agora402.json
                      description: Agora402 listing with pricing models and quote endpoint
                      required: false
                skills:
                  - id: infer
                    name: infer
                    description: >-
                      LLM chat completion (OpenAI-compatible body). Metered per
                      token.
                    tags:
                      - x402
                      - hedera
                  - id: hbar-rate
                    name: hbar-rate
                    description: >-
                      Live HBAR/USD exchange rate from the Hedera network rate
                      file. Priced per query.
                    tags:
                      - x402
                      - hedera
components:
  schemas:
    AgentCard:
      type: object
      description: A2A agent card with the x402 extension
      required:
        - name
        - description
        - url
        - version
        - provider
        - uaid
        - capabilities
        - skills
      properties:
        name:
          type: string
        description:
          type: string
        url:
          type: string
          format: uri
        version:
          type: string
        provider:
          type: object
          properties:
            organization:
              type: string
            url:
              type: string
              format: uri
        uaid:
          $ref: '#/components/schemas/Uaid'
        capabilities:
          type: object
          properties:
            streaming:
              type: boolean
              description: Always false
            pushNotifications:
              type: boolean
              description: Always false
            extensions:
              type: array
              items:
                type: object
                properties:
                  uri:
                    type: string
                    format: uri
                  description:
                    type: string
                  required:
                    type: boolean
                  params:
                    type: object
                    description: >-
                      For the x402 extension payment_network, facilitator and
                      assets
                    additionalProperties: true
        skills:
          type: array
          items:
            type: object
            properties:
              id:
                type: string
              name:
                type: string
              description:
                type: string
              tags:
                type: array
                items:
                  type: string
    Uaid:
      type: string
      pattern: '^uaid:'
      description: HCS-14 universal agent id
      example: >-
        uaid:aid:2NEpo7TZRRrLZSi2U;uid=agora-demo-seller;registry=agora402;proto=a2a;nativeId=hedera:testnet:0.0.5001234;domain=localhost:4402

````