openapi: 3.0.3
info:
  title: Sequence Billing Schedules Quotes API
  description: 'The Sequence API lets you programmatically manage usage-based billing, pricing, and revenue orchestration - customers, usage events and usage metrics, billing schedules, invoices and credit notes, products and prices, and quotes. It is a resource-based REST API over HTTPS using standard HTTP verbs and status codes, authenticated with HTTP Basic auth (Client ID as the username and Client Secret as the password). API changes are managed with date-based versioning selected via the `sequence-version` header (for example `2024-07-30`) or the `latest` alias.


    GROUNDING NOTE (API Evangelist): This document is grounded in Sequence''s live public documentation at docs.sequencehq.com. The following operations were confirmed directly against the rendered API reference, including host and path: `GET /customers`, `POST /api/usage-events`, `GET /billing-schedules`, `GET /invoices`, and `GET /products`. Additional operations are real (their names are published in the documentation index) but their exact request/response schemas and, in some cases, exact path spelling are MODELED here and marked with `x-modeled: true`. Verify field names and payloads against the live reference before production use. Usage event ingestion is served under the `/api/` prefix; most resource operations are served at the host root.'
  version: '2024-07-30'
  contact:
    name: Sequence
    url: https://www.sequencehq.com
  x-grounding:
    confirmed:
    - GET /customers
    - POST /api/usage-events
    - GET /billing-schedules
    - GET /invoices
    - GET /products
    modeledNote: Operations not in the confirmed list are documented by name in Sequence's reference index; their schemas and some paths are modeled and flagged with x-modeled.
    source: https://docs.sequencehq.com
    reviewer: API Evangelist
    reviewed: '2026-07-12'
servers:
- url: https://eu.sequencehq.com
  description: Production (EU)
- url: https://sandbox.sequencehq.com
  description: Sandbox
security:
- basicAuth: []
tags:
- name: Quotes
  description: Quotes and quote analytics.
paths:
  /quotes:
    get:
      operationId: listQuotes
      tags:
      - Quotes
      summary: List quotes
      description: Lists quotes. Path and schema modeled from the documented "List quotes" operation.
      x-modeled: true
      responses:
        '200':
          description: A page of quotes.
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Quote'
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  responses:
    Unauthorized:
      description: Missing or invalid Basic auth credentials.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    Error:
      type: object
      description: Error envelope (modeled).
      x-modeled: true
      properties:
        error:
          type: object
          properties:
            code:
              type: string
            message:
              type: string
            details:
              type: object
              additionalProperties: true
    Quote:
      type: object
      description: Quote (modeled).
      x-modeled: true
      properties:
        id:
          type: string
        customerId:
          type: string
        status:
          type: string
          description: For example DRAFT, PUBLISHED, SIGNED, or ACCEPTED.
        currency:
          type: string
        total:
          type: number
  securitySchemes:
    basicAuth:
      type: http
      scheme: basic
      description: 'HTTP Basic authentication. The Client ID is the username and the Client Secret is the password, sent as `Authorization: Basic base64(clientId:clientSecret)`. Credentials are created in the Sequence Dashboard; the Client Secret is shown only once.'