# List off session charges

`GET /api/v1/off-session-charges`

Money taken from a customer's SAVED payment method with nobody present: the settlement behind an order edit that raised a total, an exchange that cost more, and a post-purchase upsell. Newest first. ONE LIST COVERS THE WHOLE WORKLIST. The dashboard has a second endpoint for the dunning queue; here that is ?retry_due=true, which selects failed charges whose next retry has come due. A client cannot derive that set itself, because the comparison is against the server's clock. READ status AND next_retry_at TOGETHER. failed does not mean abandoned: a failed charge carrying a next_retry_at is still on the schedule (1h, 6h, 24h, then 72h), and one carrying null has exhausted it and will never be attempted again. idempotency_key is the only link back to the operation that caused the charge, because the row carries no order id at all. It is written by the platform and names the producer and the object it settles. THIS FAMILY IS READ ONLY and there is no write half to add later. Retrying a charge presents a real person's stored card to the processor again, with no cart, no checkout and nobody present, and the retry schedule exists because issuers penalise rapid re-presentment of a decline. That decision stays with a human in the dashboard, and apiscope mints no write_off_session_charges at all. created_by and saved_payment_method_id are deliberately not published. The first is an unbounded actor stamp that would export staff identity, and the second is a handle onto a stored card mandate with no resource here to resolve it against.

## Query parameters

- `status` (pending | succeeded | failed) — The charge state. A value outside this set is a 400 rather than an ignored filter, because an unrecognised status matches no row and a reconciliation job would read its own typo as a clean ledger off a 200.
- `customer_id` (string) — One shopper's off-session charges. NOT validated against the customer table: an id that names nobody returns an empty page rather than a 404, because a customer who has never been charged off-session gives the same empty answer.
- `retry_due` (true) — true selects failed charges whose next dunning retry has come due, which is the worklist the platform is about to act on. Omit it to list every charge; false is a 400 rather than a no-op, because it reads two ways (never failed, or failed with the retry still ahead) and answering either silently would be the wrong answer with no way for a client to tell.
- `limit` (integer) — Rows per page. Out of range is a 400 rather than a silent clamp, so a client asking for more than 100 learns it did not get it.
- `after` (string) — The next_cursor from the previous page. Opaque: decode nothing from it and construct nothing by hand, since its encoding is not part of this contract. Omit it to read the first page.

## Responses

- `200` — Success
- `400` — The request was refused before any state changed. `code` is one of:

`invalid_body`, a write body this route will not take. `reason` partitions it
and `field` names the key when one key is at fault.
`invalid_query`, a query parameter, including limit and after.
`invalid_text`, a NUL byte or bytes that are not valid UTF-8 anywhere in the
path, the query or the body. Strip control characters before sending.
`idempotency_key_required`, a write sent without the Idempotency-Key header.
`invalid_request`, an Idempotency-Key longer than 255 bytes.

Routes add their own codes for rules only they know. Switch with a default arm.
- `401` — No credential, or one this API does not accept. `code` is always
`unauthorized`.

THE BODY IS DELIBERATELY UNINFORMATIVE. An expired key, a revoked key, a
publishable key, a key belonging to another merchant and a key that never
existed are all refused with the same bytes, so this response cannot be used to
probe which keys exist. Check the key's state in the dashboard rather than
inferring it here.

Send the key as `Authorization: Bearer <key>` or as `X-API-Key: <key>`. It is
never accepted in a query string.
- `403` — The key lacks the read_off_session_charges scope. `code` is `insufficient_scope` and the message names the scope to ask the merchant for.
- `429` — Too many requests. `code` is `rate_limited`.

Two limits apply independently: one on the credential and the route family,
one on the client address. The headers describe whichever has less left, so
honouring Retry-After always clears the window that bound.
- `default` — Any status this operation does not list, in the same envelope.

A 5xx means the request may or may not have applied. Retry it with the SAME
Idempotency-Key: that is the only way to find out without risking a duplicate,
and it is what the key is for.

A few 4xx conditions arrive here rather than as a listed status because they
depend on the merchant's plan or on a module being wired: 402 when a quota or a
plan limit is reached, and 503 when a capability the route needs is not
configured on this deployment. Both carry a `code` naming which.

## Example

```bash
curl --request GET \
  --url 'https://api.mercemur.com/api/v1/off-session-charges' \
  --header 'Authorization: Bearer <token>'
```