API Response Codes - TrainingPeaks/PartnersAPI GitHub Wiki

Status Codes Reason
200 Ok Success.
201 Created Successfully created.
202 Accepted Accepted for processing.
302 Object moved Typically returned by the API if your request is made over an insecure HTTP connection.
400 Bad Request One or more of the required fields are missing or incorrect. Inspect the return value for the list of errors.
401 Unauthorized Bad, expired or missing authorization header.
403 Forbidden The server understood the request but refuses to authorize it. This may be occur when trying to access data for an athlete that is no longer attached to their coaching account, or trying to access premium data for a basic athlete. Inspect the response payload for details.
405 Method Not Allowed
415 Unsupported Media Type The uploaded file could not be understood. Supported file types are .FIT, .TCX, and .PWX.
422 Unprocessable Entity The uploaded file has already been uploaded to the athlete's account.
500 Server Error There was an error on the server processing your request. Server errors are recorded and the servers are monitored for errors.
501 Not Implemented
503 Service Unavailable The server is currently unavailable. It is either overloaded or down for maintenance. Generally, this is a temporary state. You should retry your request later.

For more information see the HTTP RFC for HTTP status codes.