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OpenAPI Specification
openapi: 3.2.0
info:
title: Quaderno Authentication Contacts API
description: 'The Quaderno API is a REST API for tax compliance, invoicing, and sales tax / VAT automation. It exposes resources with predictable, account-scoped URLs and uses standard HTTP features - HTTP Basic Authentication, standard methods, and response codes. All requests and responses are JSON, and every endpoint path ends in `.json` to indicate JSON serialization.
The base URL is account-scoped: `https://ACCOUNT_NAME.quadernoapp.com/api`, where `ACCOUNT_NAME` is your Quaderno account subdomain. Authenticate with your private API key as the HTTP Basic Auth username (any value for the password). Sandbox testing is available on a separate sandbox host.
Core resources include Contacts, Items, Invoices, Credits, Estimates, Expenses, Recurring documents, Payments, Transactions, Checkout Sessions, Webhooks, and the tax engine (tax rate calculation, tax jurisdictions, tax codes, and tax ID validation). Endpoint paths and the account-scoped base URL are confirmed against Quaderno''s public developer documentation and the official quaderno-ruby SDK; request and response bodies are modeled and should be verified against the live API reference.'
version: '1.0'
contact:
name: Quaderno
url: https://developers.quaderno.io
license:
name: Proprietary
url: https://quaderno.io/terms/
servers:
- url: https://{account}.quadernoapp.com/api
description: Production (account-scoped)
variables:
account:
default: ACCOUNT_NAME
description: Your Quaderno account subdomain.
security:
- basicAuth: []
tags:
- name: Contacts
description: Customers and vendors.
paths:
/contacts.json:
get:
operationId: listContacts
tags:
- Contacts
summary: List contacts
description: Lists contacts (customers and vendors), with optional filtering and pagination.
parameters:
- $ref: '#/components/parameters/Page'
- name: q
in: query
required: false
description: Full-text search across contact fields.
schema:
type: string
responses:
'200':
description: A list of contacts.
content:
application/json:
schema:
type: array
items:
$ref: '#/components/schemas/Contact'
'401':
$ref: '#/components/responses/Unauthorized'
post:
operationId: createContact
tags:
- Contacts
summary: Create a contact
description: Creates a new contact.
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/ContactInput'
responses:
'201':
description: The created contact.
content:
application/json:
schema:
$ref: '#/components/schemas/Contact'
'401':
$ref: '#/components/responses/Unauthorized'
'422':
$ref: '#/components/responses/ValidationError'
/contacts/{id}.json:
parameters:
- $ref: '#/components/parameters/Id'
get:
operationId: getContact
tags:
- Contacts
summary: Retrieve a contact
responses:
'200':
description: The requested contact.
content:
application/json:
schema:
$ref: '#/components/schemas/Contact'
'404':
$ref: '#/components/responses/NotFound'
put:
operationId: updateContact
tags:
- Contacts
summary: Update a contact
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/ContactInput'
responses:
'200':
description: The updated contact.
content:
application/json:
schema:
$ref: '#/components/schemas/Contact'
'404':
$ref: '#/components/responses/NotFound'
'422':
$ref: '#/components/responses/ValidationError'
delete:
operationId: deleteContact
tags:
- Contacts
summary: Delete a contact
responses:
'204':
description: The contact was deleted.
'404':
$ref: '#/components/responses/NotFound'
components:
parameters:
Page:
name: page
in: query
required: false
description: Page number for paginated results (25 records per page).
schema:
type: integer
default: 1
Id:
name: id
in: path
required: true
description: The unique ID of the resource.
schema:
type: string
schemas:
Error:
type: object
properties:
error:
type: string
errors:
type: object
additionalProperties: true
Contact:
allOf:
- $ref: '#/components/schemas/ContactInput'
- type: object
properties:
id:
type: string
full_name:
type: string
created_at:
type: integer
ContactInput:
type: object
required:
- kind
properties:
kind:
type: string
enum:
- company
- person
description: Whether the contact is a company or a person.
first_name:
type: string
last_name:
type: string
contact_name:
type: string
street_line_1:
type: string
city:
type: string
postal_code:
type: string
region:
type: string
country:
type: string
description: ISO 3166-1 alpha-2 country code.
email:
type: string
tax_id:
type: string
responses:
Unauthorized:
description: Missing or invalid API key.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
NotFound:
description: The requested resource was not found.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
ValidationError:
description: The request payload failed validation.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
securitySchemes:
basicAuth:
type: http
scheme: basic
description: HTTP Basic Authentication. Use your private API key as the username; the password can be any value. API keys are managed in the Quaderno account settings.