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

> ## Agent Instructions
> When building application code, use `@naturalpay/sdk` for TypeScript or `naturalpay` for Python.
> When operating Natural directly for a user, use the payments MCP at `https://mcp.natural.com`.
> When searching Natural documentation, use the docs MCP at `https://docs.natural.com/mcp`.
> Use the Natural CLI for terminal and CI automation.
> Use REST only for unsupported languages or when the user explicitly requests raw HTTP.
> Start integration development and testing in the sandbox. Do not use production unless the user explicitly requests it.
> For sandbox requests that require `customerPartyId`, list customers first. Reuse only the intended fixture; otherwise create a customer.
> REST and SDK amounts use integer minor units. Payments MCP amounts use decimal strings with a required currency code.

# Get voice session

> Get a voice session



## OpenAPI

````yaml /api-reference/openapi.json get /voice/sessions/{voiceSessionId}
openapi: 3.1.1
info:
  title: Natural API
  version: 0.2.0
  description: >-
    Natural's payments API for autonomous agents.


    **Base URL:** `https://api.natural.com`


    AI agents, including coding agents, should prefer the hosted MCP server at
    `https://mcp.natural.com` when an MCP-aware host runs the agent, the Natural
    CLI for terminal/CI workflows, and the official SDKs for application
    runtimes they own. Use direct HTTP only for explicit low-level integrations,
    unsupported SDK gaps, or infrastructure work where REST is required.


    For support: support@natural.com
servers:
  - url: https://api.natural.com
    description: Production
security: []
tags:
  - name: Agents
    description: Agent management
  - name: Customers
    description: Customer management
  - name: Invitation Links
    description: Shareable links that offer your agents to customers
  - name: Payments
    description: Payment management
  - name: Payment Intents
    description: Accept card payments by link or voice
  - name: Card Payments
    description: Card payment attempts
  - name: Voice
    description: Collect a payment intent over a phone call
  - name: Refunds
    description: Return card payments to the payer
  - name: Chargebacks
    description: Respond to card payment chargebacks
  - name: Transactions
    description: Transaction activity and history
  - name: Transfers
    description: Deposits and withdrawals
  - name: PaymentRequests
    description: Payment request management
  - name: Approvals
    description: Approval review
  - name: Invitations
    description: Party invitation management
  - name: Parties
    description: Party and organization management
  - name: Wallets
    description: Wallet management
  - name: External Accounts
    description: Linked external bank accounts
  - name: External Parties
    description: Third parties with whom you transact over Direct
  - name: External Party Accounts
    description: Banking details belonging to external parties not on Natural
  - name: ACH
    description: Make ACH payments to external party accounts
  - name: Realtime
    description: Make realtime payments to external party accounts
  - name: Wire
    description: Send domestic wires to external party accounts
  - name: API Keys
    description: API key management
  - name: Agent Keys
    description: Agent key management
  - name: Card Sessions
    description: Let agents pay with a card without seeing the real card number
  - name: Agent Tokens
    description: Let agents spend from a mandate without seeing the real card number
  - name: Agent Cards
    description: Cards an agent requests for one purchase at one merchant
  - name: Card Transactions
    description: Purchases and refunds on Natural-issued cards
  - name: Webhooks
    description: Webhook endpoint management
  - name: Events
    description: Webhook event log
  - name: Simulations
    description: Sandbox-only simulation controls
paths:
  /voice/sessions/{voiceSessionId}:
    get:
      tags:
        - Voice
      summary: Get voice session
      description: Get a voice session
      operationId: voice.get
      parameters:
        - name: voiceSessionId
          in: path
          required: true
          schema:
            type: string
            pattern: ^vos_[0-9a-f]{32}$
            description: Voice session ID (vos_*).
        - name: customerPartyId
          in: query
          required: false
          schema:
            type: string
            pattern: ^pty_[0-9a-f]{32}$
            description: >-
              Customer party to act for (pty_*). Omit for your account's call
              log, including delegated activity. Requires authorization from
              that customer.
          allowEmptyValue: true
          allowReserved: true
        - name: X-Instance-ID
          in: header
          required: false
          schema:
            anyOf:
              - type: string
                maxLength: 1024
              - type: 'null'
          description: >-
            Caller-chosen identifier for the agent run, session, or
            conversation, required when an agent moves money.
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    $ref: '#/components/schemas/VoiceSession'
                required:
                  - data
                additionalProperties: false
                title: VoiceSessionResponse
              examples:
                default:
                  summary: Default
                  value:
                    data:
                      id: vos_019d0a1b2c3d4e5f60718293a4b5c6f0
                      type: voiceSession
                      attributes:
                        kind: payment
                        status: ended
                        referenceId: call_8842
                        callerPhone: '+14155550123'
                        dialUri: null
                        dialExpiresAt: '2026-09-09T18:15:00.000Z'
                        returnTarget: sip:agent-9920@sip.partner.example.com
                        call:
                          startedAt: '2026-09-09T18:01:05.000Z'
                          endedAt: '2026-09-09T18:02:50.000Z'
                          durationSeconds: 105
                          endedBy: assistant
                          summary: >-
                            The caller confirmed the order and paid. A return
                            transfer was requested.
                          returnRequestedAt: '2026-09-09T18:02:50.000Z'
                        completedAt: '2026-09-09T18:02:31.000Z'
                        payment:
                          outcome: paid
                          linkSentAt: null
                          failedAttempts: 0
                          failure: null
                        createdAt: '2026-09-09T18:00:00.000Z'
                        updatedAt: '2026-09-09T18:02:50.000Z'
                      relationships:
                        paymentIntent:
                          data:
                            type: paymentIntent
                            id: pmi_019d0a1b2c3d4e5f60718293a4b5c6d7
                        customerParty:
                          data:
                            type: party
                            id: pty_019cd1798d627ad9bc302511c4f2c115
          headers:
            X-RateLimit-Limit:
              description: Maximum requests allowed per window.
              schema:
                type: integer
            X-RateLimit-Remaining:
              description: Requests remaining in current window.
              schema:
                type: integer
            X-RateLimit-Reset:
              description: Unix timestamp when rate limit resets.
              schema:
                type: integer
        '400':
          description: Validation Error
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: invalid_value
                        detail: >-
                          The information you entered isn't valid. Please check
                          it and try again.
                        status: '400'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: unauthenticated
                        detail: Authentication is required.
                        status: '401'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '403':
          description: Forbidden
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: forbidden
                        detail: You do not have permission to perform this action.
                        status: '403'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '404':
          description: >-
            Not Found. Returned when the resource does not exist, or when it
            exists but is not accessible to your account. The two cases are
            intentionally indistinguishable, so that resource IDs cannot be
            enumerated by probing.
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: not_found
                        detail: The requested resource was not found.
                        status: '404'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '409':
          description: Conflict
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: conflict
                        detail: The request conflicts with the current resource state.
                        status: '409'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '422':
          description: >-
            Validation Error. The response contains one error object for each
            invalid request value.
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: invalid_value
                        detail: 'Too big: expected string to have <=80 characters'
                        status: '422'
                        source:
                          pointer: /data/attributes/description
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '428':
          description: Precondition Required
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: mfa_required
                        detail: MFA verification required
                        status: '428'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '429':
          description: Too Many Requests
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: rate_limited
                        detail: Too many requests. Please try again later.
                        status: '429'
                        meta:
                          supportId: req_a1b2c3d4e5f6
          headers:
            Retry-After:
              description: Seconds to wait before retrying.
              schema:
                type: integer
            X-RateLimit-Limit:
              description: Maximum requests allowed per window.
              schema:
                type: integer
            X-RateLimit-Remaining:
              description: Requests remaining in current window.
              schema:
                type: integer
            X-RateLimit-Reset:
              description: Unix timestamp when rate limit resets.
              schema:
                type: integer
        '500':
          description: Internal Server Error
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: server_error
                        detail: Something went wrong.
                        status: '500'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '501':
          description: Not Implemented
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: not_implemented
                        detail: This operation is not available.
                        status: '501'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '502':
          description: Bad Gateway
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: bad_gateway
                        detail: >-
                          We couldn't complete that request because one of
                          Natural's services returned an unexpected response.
                          Please try again.
                        status: '502'
                        meta:
                          supportId: req_a1b2c3d4e5f6
        '503':
          description: Service Unavailable
          content:
            application/json:
              schema:
                type: object
                properties:
                  errors:
                    type: array
                    minItems: 1
                    items:
                      type: object
                      properties:
                        code:
                          type: string
                          description: Stable lower-snake-case public error code.
                        detail:
                          type: string
                          description: Safe user-facing error detail.
                        status:
                          type: string
                          description: HTTP status code as a string.
                        source:
                          type: object
                          description: Location of the invalid request value.
                          properties:
                            pointer:
                              type: string
                              description: JSON Pointer to the invalid request value.
                            parameter:
                              type: string
                              description: Name of the invalid query parameter.
                            header:
                              type: string
                              description: Name of the invalid request header.
                          additionalProperties: false
                        meta:
                          type: object
                          description: >-
                            Additional error context, including support and
                            provider details when available.
                          properties:
                            supportId:
                              type: string
                              description: Request/support ID for troubleshooting.
                            limitScope:
                              type: string
                              enum:
                                - merchant
                                - program
                              description: >-
                                Which family of acquiring limit refused the
                                payment. Thresholds and usage are never
                                disclosed.
                            connectionStatus:
                              type: string
                              enum:
                                - login_required
                                - disconnected
                              description: >-
                                External account connection state when the error
                                is repairable by relinking.
                            provider:
                              type: object
                              description: Provider error details, when available.
                              properties:
                                name:
                                  type: string
                                  enum:
                                    - plaid
                                  description: Provider that returned the underlying error.
                                errorCode:
                                  type: string
                                  description: Provider error code, when available.
                                errorType:
                                  type: string
                                  description: Provider error type, when available.
                                requestId:
                                  type: string
                                  description: Provider request ID for troubleshooting.
                              required:
                                - name
                              additionalProperties: false
                          required:
                            - supportId
                          additionalProperties: false
                      required:
                        - code
                        - detail
                        - status
                        - meta
                      additionalProperties: false
                required:
                  - errors
                additionalProperties: false
              examples:
                default:
                  summary: Default
                  value:
                    errors:
                      - code: service_unavailable
                        detail: The service is temporarily unavailable.
                        status: '503'
                        meta:
                          supportId: req_a1b2c3d4e5f6
      security:
        - HTTPBearer: []
components:
  schemas:
    VoiceSession:
      type: object
      properties:
        id:
          type: string
          pattern: ^vos_[0-9a-f]{32}$
          description: Voice session ID (vos_*).
        type:
          description: Resource type. Always `voiceSession`.
          type: string
          enum:
            - voiceSession
        attributes:
          anyOf:
            - type: object
              properties:
                kind:
                  description: Collects payment for a payment intent.
                  type: string
                  enum:
                    - payment
                status:
                  enum:
                    - awaitingCall
                    - inProgress
                    - ended
                    - failed
                    - canceled
                    - expired
                  type: string
                  description: >-
                    Call lifecycle, independent of payment outcome. `ended`
                    requires a recorded call end. `expired` means the dial
                    window or call time limit passed without a recorded end.
                referenceId:
                  anyOf:
                    - type: string
                    - type: 'null'
                  description: Reference supplied when the session was created, or null.
                callerPhone:
                  anyOf:
                    - type: string
                    - type: 'null'
                  description: >-
                    Supplied caller phone number, or null for a session without
                    one.
                dialUri:
                  anyOf:
                    - type: string
                    - type: 'null'
                  description: >-
                    Dial destination while the session accepts a call and you
                    have permission to create payment voice sessions. Otherwise
                    null.
                dialExpiresAt:
                  type: string
                  description: >-
                    RFC 3339 deadline for starting the session's one permitted
                    call.
                returnTarget:
                  anyOf:
                    - type: string
                    - type: 'null'
                  description: >-
                    Requested return destination, or null. This does not confirm
                    the destination answered.
                call:
                  type: object
                  properties:
                    startedAt:
                      anyOf:
                        - type: string
                        - type: 'null'
                      description: >-
                        Reported call start time in RFC 3339, or null when
                        unavailable.
                    endedAt:
                      anyOf:
                        - type: string
                        - type: 'null'
                      description: >-
                        Time the call was recorded as ended in RFC 3339, or
                        null.
                    durationSeconds:
                      anyOf:
                        - type: integer
                          minimum: 0
                        - type: 'null'
                      description: Reported call duration in seconds, or null.
                    endedBy:
                      anyOf:
                        - enum:
                            - caller
                            - assistant
                            - unknown
                          type: string
                        - type: 'null'
                      description: >-
                        Reported party ending the call. Null before an end is
                        recorded.
                    summary:
                      anyOf:
                        - type: string
                        - type: 'null'
                      description: Redacted call summary, or null.
                    returnRequestedAt:
                      anyOf:
                        - type: string
                        - type: 'null'
                      description: >-
                        Time a return transfer was requested in RFC 3339, or
                        null. This does not confirm the return leg connected.
                  required:
                    - startedAt
                    - endedAt
                    - durationSeconds
                    - endedBy
                    - summary
                    - returnRequestedAt
                  additionalProperties: false
                  title: VoiceSessionCall
                completedAt:
                  anyOf:
                    - type: string
                    - type: 'null'
                  description: >-
                    RFC 3339 time the session completed, or null. Set once the
                    call has ended and the kind's block holds its result.
                    `voiceSession.completed` fires then.
                createdAt:
                  type: string
                  description: RFC 3339 time the session was created.
                updatedAt:
                  type: string
                  description: RFC 3339 time the stored session last changed.
                payment:
                  type: object
                  properties:
                    outcome:
                      anyOf:
                        - enum:
                            - paid
                            - linkSent
                            - unpaid
                          type: string
                        - type: 'null'
                      description: >-
                        `paid` when the card was charged on the call. `linkSent`
                        when voice payment did not succeed and the caller was
                        texted the payment link. `unpaid` otherwise. Null until
                        the result is known, which can be while the call is
                        still in progress. A later link payment does not change
                        it. New values may be added.
                    linkSentAt:
                      anyOf:
                        - type: string
                        - type: 'null'
                      description: >-
                        RFC 3339 time the payment link was texted to the caller,
                        or null.
                    failedAttempts:
                      type: integer
                      minimum: 0
                      description: Card payments that failed during this session.
                    failure:
                      anyOf:
                        - type: object
                          properties:
                            code:
                              anyOf:
                                - type: string
                                - type: 'null'
                              description: >-
                                Failure code, when known. New codes may be
                                added.
                            reason:
                              anyOf:
                                - type: string
                                - type: 'null'
                              description: Explanation of the failure.
                            advice:
                              anyOf:
                                - enum:
                                    - doNotRetry
                                    - tryAgainLater
                                    - confirmCardData
                                  type: string
                                - type: 'null'
                              description: Recommended payer action, when known.
                          required:
                            - code
                            - reason
                            - advice
                          additionalProperties: false
                        - type: 'null'
                      description: The last failed card payment in this session, or null.
                  required:
                    - outcome
                    - linkSentAt
                    - failedAttempts
                    - failure
                  additionalProperties: false
                  title: VoiceSessionPayment
              required:
                - kind
                - status
                - referenceId
                - callerPhone
                - dialUri
                - dialExpiresAt
                - returnTarget
                - call
                - completedAt
                - createdAt
                - updatedAt
                - payment
              additionalProperties: false
              title: PaymentVoiceSessionAttributes
          title: VoiceSessionAttributes
          description: >-
            `kind` is the session's purpose and names the block that holds its
            result. New kinds may be added; ignore kinds you don't handle.
        relationships:
          type: object
          properties:
            paymentIntent:
              type: object
              properties:
                data:
                  anyOf:
                    - type: object
                      properties:
                        type:
                          description: Resource type. Always `paymentIntent`.
                          type: string
                          enum:
                            - paymentIntent
                        id:
                          type: string
                          pattern: ^pmi_[0-9a-f]{32}$
                      required:
                        - type
                        - id
                      additionalProperties: false
                      title: ResourceIdentifier
                      description: Related resource identifier.
                    - type: 'null'
              required:
                - data
              additionalProperties: false
              title: NullableToOneRelationship
              description: Associated payment intent. Set on `payment` sessions.
            customerParty:
              type: object
              properties:
                data:
                  anyOf:
                    - type: object
                      properties:
                        type:
                          description: Resource type. Always `party`.
                          type: string
                          enum:
                            - party
                        id:
                          type: string
                          pattern: ^pty_[0-9a-f]{32}$
                      required:
                        - type
                        - id
                      additionalProperties: false
                      title: ResourceIdentifier
                      description: Related resource identifier.
                    - type: 'null'
              required:
                - data
              additionalProperties: false
              title: NullableToOneRelationship
              description: Associated Natural customer, or null when none is associated.
          required:
            - paymentIntent
            - customerParty
          additionalProperties: false
          title: VoiceSessionRelationships
      required:
        - id
        - type
        - attributes
        - relationships
      additionalProperties: false
      title: VoiceSessionResource
  securitySchemes:
    HTTPBearer:
      type: http
      scheme: bearer
      description: >-
        Bearer authentication: send your API key, agent key, or OAuth access
        token as `Authorization: Bearer <credential>`.

````

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