curl --request POST \
  --url https://commet.co/api/v1/transactions/{id}/refund \
  --header 'x-api-key: <api-key>'

import { Commet } from "@commet/node";

const commet = new Commet({ apiKey: "ck_xxx" });

const refund = await commet.transactions.refund({ id: "transaction_xxx" });

from commet import Commet

commet = Commet("ck_xxx")

refund = commet.transactions.refund("transaction_xxx")

client, err := commet.New("ck_xxx")
if err != nil {
	log.Fatal(err)
}
ctx := context.Background()

refund, err := client.Transactions.Refund(ctx, "transaction_xxx", nil)
if err != nil {
	log.Fatal(err)
}

import co.commet.Commet;
import co.commet.params.RefundTransactionParams;

var commet = Commet.builder().apiKey("ck_xxx").build();

var refund = commet.transactions().refund(
    "transaction_xxx",
    RefundTransactionParams.builder().build()
);

use Commet\Commet;

$commet = new Commet('ck_xxx');

$refund = $commet->transactions->refund(id: 'transaction_xxx');

{
  "id": "ref_1a2b3c4d",
  "transactionId": "txn_1a2b3c4d",
  "amount": 2000,
  "currency": "usd",
  "chargeId": "charge_1a2b3c4d",
  "status": "succeeded",
  "reason": "requested_by_customer",
  "object": "refund",
  "livemode": false
}

{
  "error": {
    "type": "validation_error",
    "code": "validation_error",
    "message": "The request contains an invalid parameter.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/validation_error.md"
  }
}

{
  "error": {
    "type": "authentication_error",
    "code": "unauthorized",
    "message": "A valid API key is required.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/unauthorized.md"
  }
}

{
  "error": {
    "type": "authentication_error",
    "code": "forbidden",
    "message": "You do not have permission to perform this operation.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/forbidden.md"
  }
}

{
  "error": {
    "type": "not_found_error",
    "code": "not_found",
    "message": "The requested resource was not found.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/not_found.md"
  }
}

{
  "error": {
    "type": "conflict_error",
    "code": "idempotency_in_progress",
    "message": "A request with this idempotency key is still being processed.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_in_progress.md"
  }
}

{
  "error": {
    "type": "rate_limit_error",
    "code": "rate_limited",
    "message": "Too many requests. Retry after the interval specified in the Retry-After header.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/rate_limited.md"
  }
}

{
  "error": {
    "type": "internal_error",
    "code": "internal_error",
    "message": "An unexpected error occurred while processing the request.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/internal_error.md"
  }
}

{
  "error": {
    "type": "internal_error",
    "code": "idempotency_unavailable",
    "message": "Idempotency storage is temporarily unavailable. Retry with the same idempotency key.",
    "doc_url": "https://commet.co/docs/api-reference/2026-08-27/errors/idempotency_unavailable.md"
  }
}