openapi: 3.2.0
info:
  title: 'GTM API public contract: gtm.service.id Billing Payment…'
  description: 'Identity, access and money: users, teams and members, API keys, OAuth clients and authorizations, billing products, subscriptions, transactions and payment methods, notifications, TLS certificates and support requests.'
  version: '1.0'
  contact:
    name: GTM API
    url: https://gtm-api.com
    email: support@gtm-api.com
  license:
    name: Proprietary
    url: https://gtm-api.com/license
servers:
- url: https://app.gtm-api.com/id/v4
  description: Production, through the app.gtm-api.com gateway
security:
- BearerJwt: []
  TeamSid: []
tags:
- name: billing_payment_methods
  description: Registry package `mcp.id/billing_payment_methods`, served on MCP mount `id.billing`.
paths:
  /api/billing-payment-methods:
    get:
      operationId: list_billing_payment_methods
      summary: List payment methods
      description: 'List the saved cards / PayPal / wallets for the active workspace''s paying user (proxied live from Paddle). The list is re-sorted so the billing card is items[0]; is_default:true is the card that last billed the workspace, so answer ''which card am I paying with'' by reading it. Cards may be listed even with no applied subscription; empty if the user has no Paddle customer. Brand + last4 + expiry only (PCI). Requires billing.view.


        Contract:

        - MCP tool `list_billing_payment_methods`, registry package `mcp.id/billing_payment_methods`, mount `id.billing`.

        - Operation `search`, response envelope `search`.

        - Flags: read only.'
      tags:
      - billing_payment_methods
      responses:
        '200':
          description: '`search` success envelope.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ListBillingPaymentMethodsResponse'
        4XX:
          $ref: '#/components/responses/McpClientError'
        5XX:
          $ref: '#/components/responses/McpServerError'
      x-gtm-mcp-tool: list_billing_payment_methods
      x-gtm-mcp-mount: id.billing
      x-gtm-entity: billing_payment_methods
      x-gtm-operation: search
      x-gtm-envelope: search
      x-gtm-availability: ga
      x-gtm-dangerous: false
      x-gtm-mass-action: false
      x-gtm-step-eligible: false
      x-gtm-schedule-required: false
      x-gtm-tool-class: typical
  /api/billing-payment-methods/get-add-link:
    post:
      operationId: get_billing_payment_method_add_link
      summary: Get add-card link
      description: 'Return a temporary Paddle Customer Portal deep link to add or replace a card for the workspace''s applied subscription. This is the ONLY way to add a card: Paddle has no add-card API; the user enters card details on Paddle''s hosted page. Never cached. Returns no_billing_account if the workspace has no applied subscription. Requires billing.manage.


        Contract:

        - MCP tool `get_billing_payment_method_add_link`, registry package `mcp.id/billing_payment_methods`, mount `id.billing`.

        - Operation `action`, response envelope `action`.

        - Flags: none.'
      tags:
      - billing_payment_methods
      responses:
        '200':
          description: '`action` success envelope.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GetBillingPaymentMethodAddLinkResponse'
        4XX:
          $ref: '#/components/responses/McpClientError'
        5XX:
          $ref: '#/components/responses/McpServerError'
      x-gtm-mcp-tool: get_billing_payment_method_add_link
      x-gtm-mcp-mount: id.billing
      x-gtm-entity: billing_payment_methods
      x-gtm-operation: action
      x-gtm-envelope: action
      x-gtm-availability: ga
      x-gtm-dangerous: false
      x-gtm-mass-action: false
      x-gtm-step-eligible: false
      x-gtm-schedule-required: false
      x-gtm-tool-class: typical
  /api/billing-payment-methods/{sid}:
    delete:
      operationId: delete_billing_payment_method
      summary: Delete payment method
      description: 'Remove a saved payment method: this only takes it off the paying user''s saved list in Paddle. A method a live subscription uses is refused (409 conflict, payment_method_in_use) until that subscription is moved to another card via get_billing_payment_method_add_link: always the case for is_default:true while the plan bills it. A non-default card can be refused too, when it pays another subscription of the same payer (another workspace or a floating one). Idempotent. Requires billing.manage.


        Contract:

        - MCP tool `delete_billing_payment_method`, registry package `mcp.id/billing_payment_methods`, mount `id.billing`.

        - Operation `delete`, response envelope `delete_simple`.

        - Flags: dangerous: the MCP layer gates it behind a preview/commit token, and the effect cannot be undone through this API.'
      tags:
      - billing_payment_methods
      parameters:
      - name: sid
        in: path
        required: true
        description: 'Paddle payment-method id (paymtd_…): a raw Paddle id, not an 18-char platform sid.'
        schema:
          type: string
          pattern: ^paymtd_
          description: 'Paddle payment-method id (paymtd_…): a raw Paddle id, not an 18-char platform sid.'
      responses:
        '200':
          description: '`delete_simple` success envelope.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DeleteBillingPaymentMethodResponse'
        4XX:
          $ref: '#/components/responses/McpClientError'
        5XX:
          $ref: '#/components/responses/McpServerError'
      x-gtm-mcp-tool: delete_billing_payment_method
      x-gtm-mcp-mount: id.billing
      x-gtm-entity: billing_payment_methods
      x-gtm-operation: delete
      x-gtm-envelope: delete_simple
      x-gtm-availability: ga
      x-gtm-dangerous: true
      x-gtm-mass-action: false
      x-gtm-step-eligible: false
      x-gtm-schedule-required: false
      x-gtm-tool-class: typical
components:
  schemas:
    McpError:
      type: object
      properties:
        success:
          type: boolean
          enum:
          - false
        error:
          type: object
          properties:
            code:
              type: string
              enum:
              - validation_failed
              - nothing_to_update
              - not_found
              - relation_not_found
              - invalid_transition
              - limit_exceeded
              - payment_required
              - duplicate_rejected
              - conflict
              - delete_blocked
              - unauthorized
              - forbidden
              - rate_limited
              - internal_error
              - service_unavailable
              - not_implemented
            message:
              type: string
            recoverable:
              type: boolean
            suggestion:
              type: string
            field_errors:
              type: object
              additionalProperties:
                type: array
                items:
                  type: object
                  properties:
                    rule:
                      type: string
                    message:
                      type: string
                  required:
                  - rule
                  - message
            blockers:
              type: array
              items:
                type: object
                properties:
                  type:
                    type: string
                    description: Machine-readable blocker type (active_flow, pending_tasks, …).
                  severity:
                    type: string
                    enum:
                    - hard
                    - soft
                    description: hard = external action required; soft = acknowledge is enough.
                  description:
                    type: string
                  entity_sid:
                    type:
                    - string
                    - 'null'
                  count:
                    type: integer
                  resolution:
                    type: string
                    description: 'Hard: tool name to call. Soft: code for acknowledge[].'
                  resolution_hint:
                    type: string
                required:
                - type
                - severity
                - description
                - entity_sid
                - resolution
                - resolution_hint
            context:
              type: object
              additionalProperties: {}
          required:
          - code
          - message
          - recoverable
        meta:
          type: object
          properties:
            trace_id:
              type: string
              description: UUID v7; same 128-bit value as the X-Trace-Id header.
            span_id:
              type: string
              pattern: ^[0-9a-f]{16}$
              description: 16 hex chars, root span of this request.
            timestamp:
              type: string
              description: ISO 8601 UTC (Y-m-dTH:i:sZ), response time.
            duration_ms:
              type: integer
              minimum: 0
              description: Server-side wall clock.
            team_sid:
              type:
              - string
              - 'null'
              description: The team this call ran in (the token team, or the team_sid override). Null when unauthenticated; absent from pre-2026-08-20 backends.
            actor_type:
              type:
              - string
              - 'null'
              description: user | agent | api_key | system. Null when unauthenticated; absent from pre-2026-08-20 backends.
          required:
          - trace_id
          - span_id
          - timestamp
          - duration_ms
      required:
      - success
      - error
    ListBillingPaymentMethodsResponse:
      type: object
      properties:
        success:
          type: boolean
          enum:
          - true
        operation:
          type: string
          enum:
          - search
        items:
          type: array
          items:
            type: object
            properties:
              item:
                type: object
                properties:
                  sid:
                    type: string
                  type:
                    type: string
                    enum:
                    - card
                    - paypal
                    - apple_pay
                    - google_pay
                    - other
                  card_brand:
                    type:
                    - string
                    - 'null'
                  card_last4:
                    type:
                    - string
                    - 'null'
                  card_expiry:
                    type:
                    - string
                    - 'null'
                  is_default:
                    type: boolean
                  origin:
                    type:
                    - string
                    - 'null'
                  saved_at:
                    type:
                    - string
                    - 'null'
                required:
                - sid
                - type
                - card_brand
                - card_last4
                - card_expiry
                - is_default
                - origin
                - saved_at
              included:
                type: object
                additionalProperties: {}
            required:
            - item
            - included
        pagination:
          type: object
          properties:
            next_cursor:
              type:
              - string
              - 'null'
            has_more:
              type: boolean
            total_count:
              type:
              - integer
              - 'null'
          required:
          - next_cursor
          - has_more
          - total_count
        applied_filters:
          type: object
          additionalProperties: {}
        includes:
          type: array
          items:
            type: string
        meta:
          type: object
          properties:
            trace_id:
              type: string
              description: UUID v7; same 128-bit value as the X-Trace-Id header.
            span_id:
              type: string
              pattern: ^[0-9a-f]{16}$
              description: 16 hex chars, root span of this request.
            timestamp:
              type: string
              description: ISO 8601 UTC (Y-m-dTH:i:sZ), response time.
            duration_ms:
              type: integer
              minimum: 0
              description: Server-side wall clock.
            team_sid:
              type:
              - string
              - 'null'
              description: The team this call ran in (the token team, or the team_sid override). Null when unauthenticated; absent from pre-2026-08-20 backends.
            actor_type:
              type:
              - string
              - 'null'
              description: user | agent | api_key | system. Null when unauthenticated; absent from pre-2026-08-20 backends.
          required:
          - trace_id
          - span_id
          - timestamp
          - duration_ms
        counts:
          type: object
          additionalProperties: {}
      required:
      - success
      - operation
      - items
      - pagination
      - applied_filters
      - includes
      - meta
    GetBillingPaymentMethodAddLinkResponse:
      type: object
      properties:
        success:
          type: boolean
          enum:
          - true
        operation:
          type: string
          enum:
          - action
        action:
          type: string
          description: kebab-case verb; matches the route segment.
        item: {}
        result:
          type: object
          properties:
            add_link:
              type:
              - string
              - 'null'
            expires_at:
              type: string
            subscription_sid:
              type: string
          required:
          - add_link
          - expires_at
          - subscription_sid
        meta:
          type: object
          properties:
            trace_id:
              type: string
              description: UUID v7; same 128-bit value as the X-Trace-Id header.
            span_id:
              type: string
              pattern: ^[0-9a-f]{16}$
              description: 16 hex chars, root span of this request.
            timestamp:
              type: string
              description: ISO 8601 UTC (Y-m-dTH:i:sZ), response time.
            duration_ms:
              type: integer
              minimum: 0
              description: Server-side wall clock.
            team_sid:
              type:
              - string
              - 'null'
              description: The team this call ran in (the token team, or the team_sid override). Null when unauthenticated; absent from pre-2026-08-20 backends.
            actor_type:
              type:
              - string
              - 'null'
              description: user | agent | api_key | system. Null when unauthenticated; absent from pre-2026-08-20 backends.
          required:
          - trace_id
          - span_id
          - timestamp
          - duration_ms
      required:
      - success
      - operation
      - action
      - item
      - result
      - meta
    DeleteBillingPaymentMethodResponse:
      type: object
      properties:
        success:
          type: boolean
          enum:
          - true
        operation:
          type: string
          enum:
          - delete
        item:
          type: object
          additionalProperties: {}
        already_deleted:
          type: boolean
        soft_deleted:
          type: boolean
        retained:
          type: array
          items:
            type: string
        meta:
          type: object
          properties:
            trace_id:
              type: string
              description: UUID v7; same 128-bit value as the X-Trace-Id header.
            span_id:
              type: string
              pattern: ^[0-9a-f]{16}$
              description: 16 hex chars, root span of this request.
            timestamp:
              type: string
              description: ISO 8601 UTC (Y-m-dTH:i:sZ), response time.
            duration_ms:
              type: integer
              minimum: 0
              description: Server-side wall clock.
            team_sid:
              type:
              - string
              - 'null'
              description: The team this call ran in (the token team, or the team_sid override). Null when unauthenticated; absent from pre-2026-08-20 backends.
            actor_type:
              type:
              - string
              - 'null'
              description: user | agent | api_key | system. Null when unauthenticated; absent from pre-2026-08-20 backends.
          required:
          - trace_id
          - span_id
          - timestamp
          - duration_ms
      required:
      - success
      - operation
      - item
      - already_deleted
      - soft_deleted
      - retained
      - meta
  responses:
    McpServerError:
      description: MCP error envelope with `error.code` internal_error or service_unavailable.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/McpError'
    McpClientError:
      description: MCP error envelope. `error.code` is one of validation_failed, nothing_to_update, not_found, relation_not_found, invalid_transition, limit_exceeded, payment_required, duplicate_rejected, conflict, delete_blocked, unauthorized, forbidden, rate_limited, not_implemented.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/McpError'
  securitySchemes:
    BearerJwt:
      type: http
      scheme: bearer
      bearerFormat: JWT
      description: Access token issued by gtm.service.id. Its `access_identity` claim carries `team_sid`, `actor_sid` and `actor_type`, and that team scope is authoritative.
    TeamSid:
      type: apiKey
      in: header
      name: Team-SID
      description: Team scope for tokens that do not carry one. Ignored when the token already names a team.