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

# Pay an agent top-up

> Pays a requested top-up with a Machine Payments Protocol (MPP) payment; no bearer token is required. Without a credential the response is 402 with a `WWW-Authenticate: Payment` challenge for the top-up's amount; retry with an `Authorization: Payment` credential (a Stripe shared payment token, or a USDC transfer on Tempo) to settle it. A settled top-up returns 200 with a `Payment-Receipt` header and credits the pack once; repeated calls return its current state.



## OpenAPI

````yaml /api-reference/openapi.json post /api/billing/agent-payments/top-ups/{topUpId}/pay
openapi: 3.1.2
info:
  title: EvalGate API
  version: 18.7.0
  description: EvalGate API. See docs/api-contract.md for stability commitments.
servers:
  - url: https://evalgate.com
    description: Production
  - url: http://localhost:3000
    description: Local
security: []
paths:
  /api/billing/agent-payments/top-ups/{topUpId}/pay:
    post:
      tags:
        - billing
      summary: Pay an agent top-up
      description: >-
        Pays a requested top-up with a Machine Payments Protocol (MPP) payment;
        no bearer token is required. Without a credential the response is 402
        with a `WWW-Authenticate: Payment` challenge for the top-up's amount;
        retry with an `Authorization: Payment` credential (a Stripe shared
        payment token, or a USDC transfer on Tempo) to settle it. A settled
        top-up returns 200 with a `Payment-Receipt` header and credits the pack
        once; repeated calls return its current state.
      operationId: post_billing_agent_payments_top_ups_topUpId_pay
      parameters:
        - name: topUpId
          in: path
          required: true
          schema:
            type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: >-
                  #/components/schemas/PostApiBillingAgentPaymentsTopUpsTopUpIdPayResponse200ApplicationJson
            text/plain:
              schema:
                $ref: >-
                  #/components/schemas/PostApiBillingAgentPaymentsTopUpsTopUpIdPayResponse200TextPlain
        '400':
          $ref: '#/components/responses/ValidationError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '402':
          description: >-
            Payment required. The `WWW-Authenticate: Payment` header carries the
            challenge.
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          $ref: '#/components/responses/NotFound'
        '409':
          $ref: '#/components/responses/Conflict'
        '429':
          $ref: '#/components/responses/RateLimited'
        '500':
          $ref: '#/components/responses/InternalError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
      security: []
components:
  schemas:
    PostApiBillingAgentPaymentsTopUpsTopUpIdPayResponse200ApplicationJson:
      type: object
      properties:
        topUpId:
          type: string
        amountUsd:
          type: number
        units:
          type: number
        status:
          type: string
        payUrl:
          type: string
        expiresAt:
          type: string
        paidAt:
          oneOf:
            - type: 'null'
            - type: string
      additionalProperties: false
      required:
        - topUpId
        - amountUsd
        - units
        - status
        - payUrl
        - expiresAt
        - paidAt
    PostApiBillingAgentPaymentsTopUpsTopUpIdPayResponse200TextPlain:
      type: 'null'
    ApiError:
      type: object
      properties:
        error:
          type: object
          properties:
            code:
              type: string
              enum:
                - UNAUTHORIZED
                - FORBIDDEN
                - NOT_FOUND
                - INVALID_REFERENCE
                - VALIDATION_ERROR
                - RATE_LIMITED
                - CONFLICT
                - INTERNAL_ERROR
                - SERVICE_UNAVAILABLE
                - QUOTA_EXCEEDED
                - FEATURE_LIMIT_REACHED
                - NO_ORG_MEMBERSHIP
                - SHARE_REVOKED
                - SHARE_EXPIRED
                - SHARE_UNAVAILABLE
                - PROVIDER_KEY_MISSING
                - PROVIDER_KEY_EXPIRED
                - PROVIDER_RATE_LIMITED
                - PROVIDER_UNAUTHORIZED
                - PROVIDER_UNAVAILABLE
                - AGENT_HANDOFF_INVALID
                - AGENT_HANDOFF_EXPIRED
                - AGENT_HANDOFF_DENIED
                - AGENT_HANDOFF_CONSUMED
                - PAYLOAD_TOO_LARGE
                - METHOD_NOT_ALLOWED
            message:
              type: string
            details: {}
            requestId:
              type: string
              format: uuid
            redaction:
              type: object
              properties:
                applied:
                  type: boolean
                  enum:
                    - true
                fieldCount:
                  type: integer
                  minimum: 0
                secretCount:
                  type: integer
                  minimum: 0
              required:
                - applied
                - fieldCount
                - secretCount
          required:
            - code
            - message
      required:
        - error
  responses:
    ValidationError:
      description: Validation error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
        WWW-Authenticate:
          description: >-
            Bearer challenge. Agent-facing routes include the RFC 9728
            resource_metadata URL.
          schema:
            type: string
    Forbidden:
      description: Forbidden
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
    Conflict:
      description: Conflict
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
    RateLimited:
      description: Rate limit exceeded
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
        Retry-After:
          description: Delay in seconds before retrying when present.
          schema:
            type: integer
            minimum: 1
    InternalError:
      description: Internal server error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string
    ServiceUnavailable:
      description: Service unavailable
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
      headers:
        RateLimit-Limit:
          description: Quota in requests for the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Remaining:
          description: Remaining requests in the active window.
          schema:
            type: integer
            minimum: 0
        RateLimit-Reset:
          description: Reset delay in seconds (not a Unix timestamp).
          schema:
            type: integer
            minimum: 1
        X-RateLimit-Limit:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Remaining:
          schema:
            type: integer
            minimum: 0
        X-RateLimit-Reset:
          description: Legacy reset timestamp in Unix milliseconds.
          schema:
            type: integer
            minimum: 0
        RateLimit-Policy:
          description: IETF HTTPAPI structured quota policy (work in progress).
          schema:
            type: string
        RateLimit:
          description: >-
            IETF HTTPAPI structured remaining quota and reset delay (work in
            progress).
          schema:
            type: string

````

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