Amazon Creators API errors come as JSON with a type (the exception), a message and, for 400, 401 and 403, a machine-readable reason. Look up the reason first, because it is more specific than the exception type. Codes marked “observed” are not in the official docs but were seen in real responses.
{
"type": "ValidationException",
"message": "Partner tag in the request is invalid or is not mapped to the store associated with your credential.",
"reason": "InvalidPartnerTag"
}
Authentication (401)
| Code | Meaning |
|---|
| InvalidToken | The access token in the Authorization header is broken, incomplete or in the wrong format. |
| TokenExpired | Your access token is older than one hour. Fetch a new one and try again. |
| InvalidIssuer | The token comes from the wrong token endpoint for your credential version. |
| MissingClaim | The token is missing information the API needs, usually because it was requested with the wrong scope. |
| MissingKeyId | The token was not issued by Amazon’s official token endpoint: its key ID (`kid`) is missing. |
| UnsupportedClient | The Credential ID behind the token is not registered for the Creators API. |
| InvalidClient | The token was issued for a different Credential ID than this request expects. |
| MissingCredential | The request has no Authorization header, so Amazon does not know who you are. |
| UnauthorizedException | Amazon could not verify who you are. The `reason` field says why. |
Access & eligibility (403)
| Code | Meaning |
|---|
| AssociateNotEligible | Your credentials are valid, but your Associates account currently does not qualify for API access (10 qualified sales in the last 30 days). |
| AuthorizationFailed | Your login worked, but this credential may not use the API, most often because the credential itself has expired. |
| AccessDeniedException | Amazon refused the request for your account or credential. The `reason` field says why. |
Request validation (400)
| Code | Meaning |
|---|
| InvalidPartnerTag | The partner tag is wrong, or it belongs to a different Associates account than your credential. |
| InvalidAssociate | Your credential and the partner tag do not belong together for this marketplace (different accounts, or no API access there). |
| FieldValidationFailed | A required field is missing or has an invalid value. The `fieldList` in the response names it. |
| CannotParse | The request body is not valid JSON. |
| UnknownOperation | The operation in the URL does not exist. |
| ValidationException | The request breaks one of the API’s rules. The `reason` field says which one. |
Not found (404)
| Code | Meaning |
|---|
| ResourceNotFoundException | Your credentials worked, but none of the requested products, categories or search results exist in this marketplace. |
Throttling (429)
| Code | Meaning |
|---|
| ThrottleException | You sent more requests than your limit allows, either per second or per day. |
Server errors (5xx)
| Code | Meaning |
|---|
| InternalServerException | Something went wrong on Amazon’s side, not in your request. Try again in a moment. |
Token endpoint
| Code | Meaning |
|---|
| invalid_client (observed) | Amazon’s token endpoint rejected your Credential ID or Secret, so no access token was issued. |
| too_many_requests | You fetched new access tokens too often. A token is valid for an hour, so reuse it instead of fetching one per request. |
Partial errors (HTTP 200)
| Code | Meaning |
|---|
| InvalidParameterValue | Some of the requested IDs are invalid. You still get the data for the valid ones. |
| ItemNotFound | One of the requested products was not found. You still get the others. |
PA-API 5.0 (deprecated)
| Code | Meaning |
|---|
| AccessDenied (PA-API 5.0) | Your code still calls the Product Advertising API 5.0, which Amazon shut down on May 15, 2026. |