Errors

Muamla uses conventional HTTP status codes. Every error response has the same JSON shape.

json

{
  "error": {
    "code": "invalid_amount",
    "message": "amount must be an integer ≥ 100 (smallest MRU unit)."
  }
}

Status codes

HTTP	Meaning
`200` / `201`	Success.
`400`	Validation error — check the message.
`401`	Missing, malformed, or invalid API key / credentials.
`403`	The key type isn't allowed (e.g. a publishable key on a secret-only endpoint).
`404`	The resource doesn't exist.
`409`	Conflict (e.g. the invoice has expired).
`500`	Unexpected server error — safe to retry.
`501`	Not implemented yet (e.g. live bank verification).
`503`	Service not configured (database unavailable).

Code	HTTP	When
`unauthorized`	401	No / invalid / revoked API key.
`forbidden`	403	Secret key required for this endpoint.
`invalid_amount`	400	`amount` missing or below 100.
`invalid_description`	400	`description` missing.
`invalid_phone`	400	`phone` missing when submitting a payment.
`not_found`	404	Invoice not found.
`invoice_expired`	409	Payment attempted after `expired_at`.
`not_implemented`	501	Live bank verification not enabled yet.
`internal_error`	500	Unexpected error — retry with backoff.

Retry on 500 and network/timeout errors with exponential backoff. Do not retry 400/401/403/404 — fix the request instead.