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

# x402 支付

> 为目标 URL 触发 x402 支付协商。

为目标 URL 协商并完成一次 x402 支付。AgentWallex 评估代理的策略，通过 MPC 签署支付，并返回访问付费资源所需的支付信息。

## 请求体

<ParamField body="agent_id" type="string" required>
  将为支付提供资金的代理。
</ParamField>

<ParamField body="target_url" type="string" required>
  要支付的 x402 启用的 URL（例如 `https://paid-api.example.com/v1/data`）。
</ParamField>

<ParamField body="session_id" type="string">
  可选的会话 ID，用于从现有会话预算中扣除。请参阅 [x402 会话](/zh/api-reference/x402-sessions)。
</ParamField>

<ParamField body="chain" type="string">
  用于支付结算的 CAIP-2 链标识符（例如 `eip155:84532`）。如果省略，则使用代理的默认链。
</ParamField>

## 响应

<Expandable title="响应字段">
  <ParamField body="ledger_id" type="string">
    此支付的内部账本条目 ID。
  </ParamField>

  <ParamField body="amount" type="string">
    支付金额。
  </ParamField>

  <ParamField body="fee_amount" type="string">
    平台扣除的费用。
  </ParamField>

  <ParamField body="fee_rate" type="string">
    适用的费率百分比（基于分层定价）。
  </ParamField>

  <ParamField body="token" type="string">
    用于支付的代币（例如 `USDC`）。
  </ParamField>

  <ParamField body="chain" type="string">
    用于结算的链。
  </ParamField>

  <ParamField body="status" type="string">
    支付状态：`completed`、`pending`、`failed`。
  </ParamField>

  <ParamField body="payment_signature" type="string">
    重试请求目标 URL 时需要包含的 `PAYMENT-SIGNATURE` 值。
  </ParamField>
</Expandable>

## 示例

<CodeGroup>
  ```bash cURL theme={null}
  curl -X POST https://api.agentwallex.com/api/v1/x402/pay \
    -H "X-API-Key: awx_your_api_key" \
    -H "Content-Type: application/json" \
    -d '{
      "agent_id": "agent_abc123",
      "target_url": "https://paid-api.example.com/v1/data",
      "session_id": "sess_xyz789",
      "chain": "eip155:84532"
    }'
  ```

  ```typescript TypeScript theme={null}
  const result = await aw.x402.pay({
    agentId: "agent_abc123",
    targetUrl: "https://paid-api.example.com/v1/data",
    sessionId: "sess_xyz789",
    chain: "eip155:84532",
  });
  ```

  ```python Python theme={null}
  result = await aw.x402.pay(
      agent_id="agent_abc123",
      target_url="https://paid-api.example.com/v1/data",
      session_id="sess_xyz789",
      chain="eip155:84532",
  )
  ```
</CodeGroup>

```json Response theme={null}
{
  "ledger_id": "ldg_abc123",
  "amount": "0.10",
  "fee_amount": "0.002",
  "fee_rate": "2.0",
  "token": "USDC",
  "chain": "eip155:84532",
  "status": "completed",
  "payment_signature": "base64_encoded_signature..."
}
```

## 相关端点

| 端点                                | 说明                    |
| --------------------------------- | --------------------- |
| `POST /x402/check`                | 检查 URL 是否支持 x402 支付协商 |
| `POST /x402/facilitator/verify`   | 验证支付签名（面向服务提供商）       |
| `POST /x402/facilitator/settle`   | 结算已验证的支付（面向服务提供商）     |
| `GET /x402/facilitator/supported` | 列出 x402 支持的链          |
| `GET /x402/fees/tiers`            | 获取当前费率层级表             |


## OpenAPI

````yaml POST /api/v1/x402/pay
openapi: 3.1.0
info:
  title: AgentWallex API
  description: >-
    REST API for managing AI agent wallets, on-chain transactions, spending
    policies, webhooks, and x402 micropayments.
  version: 1.0.0
  contact:
    name: AgentWallex Support
    url: https://agentwallex.com
servers:
  - url: https://api.agentwallex.com
    description: Production
  - url: https://api-sandbox.agentwallex.com
    description: Sandbox
security:
  - ApiKeyAuth: []
  - BearerAuth: []
tags:
  - name: Agents
    description: Create and manage AI agent wallets.
  - name: Transactions
    description: Send payments and query transaction history.
  - name: Policies
    description: Configure spending limits and access controls.
  - name: Webhooks
    description: Register and manage webhook endpoints.
  - name: x402
    description: x402 micropayment negotiation and session management.
paths:
  /api/v1/x402/pay:
    post:
      tags:
        - x402
      summary: x402 Pay
      description: >-
        Negotiate and complete one x402 payment for a target URL. AgentWallex
        evaluates the agent's policies, signs the payment via MPC, and returns
        the payment info needed to access the paid resource.
      operationId: x402Pay
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - agent_id
                - target_url
              properties:
                agent_id:
                  type: string
                  description: The agent whose wallet will fund the payment.
                target_url:
                  type: string
                  format: uri
                  description: >-
                    The x402-enabled URL to pay for (e.g.,
                    `https://paid-api.example.com/v1/data`).
                session_id:
                  type: string
                  description: >-
                    Optional session ID to deduct from an existing session
                    budget.
                chain:
                  type: string
                  description: >-
                    CAIP-2 chain identifier for payment settlement (e.g.,
                    `eip155:84532`). If omitted, the agent's default chain is
                    used.
            example:
              agent_id: agent_abc123
              target_url: https://paid-api.example.com/v1/data
              session_id: sess_xyz789
              chain: eip155:84532
      responses:
        '200':
          description: Payment completed successfully.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/X402PayResult'
              example:
                ledger_id: ldg_abc123
                amount: '0.10'
                fee_amount: '0.002'
                fee_rate: '2.0'
                token: USDC
                chain: eip155:84532
                status: completed
                payment_signature: base64_encoded_signature...
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '429':
          $ref: '#/components/responses/RateLimited'
        '500':
          $ref: '#/components/responses/InternalError'
components:
  schemas:
    X402PayResult:
      type: object
      description: Result of an x402 payment negotiation.
      properties:
        ledger_id:
          type: string
          description: Internal ledger entry ID for this payment.
        amount:
          type: string
          description: Payment amount.
        fee_amount:
          type: string
          description: Platform fee deducted.
        fee_rate:
          type: string
          description: Fee percentage applied (based on tiered pricing).
        token:
          type: string
          description: Token used for payment (e.g., `USDC`).
        chain:
          type: string
          description: Chain used for settlement.
        status:
          type: string
          enum:
            - completed
            - pending
            - failed
          description: Payment status.
        payment_signature:
          type: string
          description: >-
            The `PAYMENT-SIGNATURE` value to include in the retry request to the
            target URL.
    ErrorResponse:
      type: object
      description: Standard error response.
      required:
        - code
        - type
        - message
      properties:
        code:
          type: string
          description: Machine-readable error code.
        type:
          type: string
          enum:
            - invalid_request_error
            - authentication_error
            - authorization_error
            - not_found_error
            - rate_limit_error
            - internal_error
          description: Error type category.
        message:
          type: string
          description: Human-readable error description.
  responses:
    BadRequest:
      description: Invalid request body or parameters.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            code: invalid_request
            type: invalid_request_error
            message: The request body is missing required fields.
    Unauthorized:
      description: Missing or invalid credentials.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            code: authentication_failed
            type: authentication_error
            message: The provided API key is invalid or expired.
    Forbidden:
      description: Insufficient permissions.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            code: insufficient_permissions
            type: authorization_error
            message: You do not have permission to perform this action.
    RateLimited:
      description: Rate limit exceeded.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            code: rate_limit_exceeded
            type: rate_limit_error
            message: Too many requests. Please retry after a short delay.
    InternalError:
      description: Server-side error.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            code: server_error
            type: internal_error
            message: An unexpected error occurred. Please try again later.
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: API key authentication. Keys are prefixed with `awx_`.
    BearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: JWT bearer token authentication.

````