Our API responses will follow this structure in the case of any failures: 
{
  "code": "<ErrorCode>",
  "message": ""
}
Our APIs may return a failure response based on following scenarios:
  1. Input Validation: We perform JSON validation for inputs so you may expect a 400 response if required fields are missing or are invalid.
  2. Missing Records: There may be situations where the requested record, such as a contact or property doesn’t exist in Fello, in such cases you can expect a 404 response.
  3. Scenario-Based Validation: There may be cases which may reject the API due to product-level validations, such as invalid addresses, which can also cause a 400 response.
  4. Too Many Requests: See Rate Limiting for more details.
  5. Server Issues: In rare cases our APIs may throw intermittent errors due to unforeseen server issues.

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Error Codes

Following are the error codes which may be returned in case of scenarios mentioned above:
CodeEnum Value
ContactDoesNotExistRequested Contact Not Found
PropertyDoesNotExistRequested Property Not Found
InvalidAddressInvalid Address - Address Validation failed
DuplicatePropertyDuplicate Property - When trying to add a new address to an existing contact
DuplicateContactDuplicate Contact - Contact with same email id already exists
InvalidRequestRequest is invalid - could be due to JSON validation or situational based. There will also be supporting data in "data" object to support the validation.