INVALID_API_KEY
Message. apiKeyHash in IOU did not match expected HMAC
Hint. Re-fetch the 402 response to pick up the current developerSalt, then re-sign.
Wire shape
{
"error": {
"code": "INVALID_API_KEY",
"message": "apiKeyHash in IOU did not match expected HMAC",
"hint": "Re-fetch the 402 response to pick up the current developerSalt, then re-sign.",
"docsUrl": "https://docs.tollgatepay.com/errors/invalid-api-key"
}
}Canonical URL
https://docs.tollgatepay.com/errors/invalid-api-key — this URL is hard-coded into the 402/403/451 docsUrl field. It is stable; renaming the slug requires a migration plan.