API introduction

The Qint merchant API is a small, server-to-server REST API around one resource: the payment intent. Create one, redirect the buyer to its checkoutUrl, and learn the outcome via webhooks or reads.

Base URL

https://qint-api.fly.dev

All endpoints are versioned under /api/v1.

api.qint.ch is the stable production hostname. Keep the base URL in configuration anyway — environment switches stay a one-line change.

Authentication

Send your qk_live_… API key with every request, either way:

-H "Authorization: Bearer qk_live_…"
# or
-H "X-Api-Key: qk_live_…"

Keys carry Read and/or Write scopes; requests outside a key’s scopes return 403. See Authentication for creation and rotation.

Errors

Errors are RFC 7807 problem documents, Content-Type: application/problem+json:

{
  "type": "https://tools.ietf.org/html/rfc9110#section-15.5.1",
  "title": "An error occurred while processing your request.",
  "status": 400,
  "detail": "Currency must be one of CHF, EUR, USD.",
  "traceId": "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-00"
}

Status	Meaning
`400`	Invalid request — bad amount, unsupported currency, malformed `returnUrl`.
`401`	Missing, malformed, revoked or unknown API key.
`403`	Key lacks the required scope (`detail` names it).
`404`	The resource doesn’t exist — or belongs to another merchant.
`429`	Rate limited — back off and retry.

Include the traceId when contacting support about a failed request.

Rate limits

The API is rate limited per client. On 429, retry with exponential backoff. Creates are retry-safe when you pass an idempotencyKey — see idempotency.

Conventions

JSON in, JSON out, camelCase field names.
Statuses are lowercase strings on the wire: initiated, pending, confirmed, settled, failed, expired, cancelled.
Crypto amounts are 8-decimal strings ("55.48765432") — parse as decimals, never floats.
Timestamps are ISO 8601 with offset.
Pagination on list endpoints: page (1-based) and pageSize (1–100, default 20); responses carry items, total, page, pageSize.
Ids are prefixed: intents pi_…, payment links pl_…, invoices inv_….

Merchant API

Payment intents

API introduction

Base URL

Authentication

Errors

Rate limits

Conventions

Endpoints

POST /api/v1/intents — Create a payment intent

GET /api/v1/intents/{id} — Retrieve a payment intent

GET /api/v1/intents — List payment intents

​Base URL

​Authentication

​Errors

​Rate limits

​Conventions

​Endpoints

POST /api/v1/intents — Create a payment intent

GET /api/v1/intents/{id} — Retrieve a payment intent

GET /api/v1/intents — List payment intents

Base URL

Authentication

Errors

Rate limits

Conventions

Endpoints