As per my understanding, SDK would make it easier. from docs -
A custom search command is an executable binary file that reads data in and writes data out. This could be a Python script, a C++ program, or some other executable binary file. For simplicity, the file is referred to as the executable in this documentation. splunk docs - https://docs.splunk.com/Documentation/Splunk/6.4.2/Search/Writeasearchcommand
