X-Yahoo-HJAuth-Token
This is session token returned by Authentication API call.
X-Yahoo-HJAuth-Timestamp
This should be the request timestamp in Unix Timestamp format (the difference, measured in milliseconds, between the current time and midnight, January 1, 1970 UTC).
X-Yahoo-HJAuth-Signature
The signature is MD5 hash of the XML request, request timestamp, job ID (empty for new job), token, and license key, respectively. The signature is also encoded in Hexadecimal format.