How to add Gatekeeper exceptions for command line tools, at the command line?

When first running a command-line tool not compiled on the local system, it is necessary to attempt to run the command, dismiss a graphical notification, open System Preferences, click "allow", attempt to run the command again, click another "allow", and finally successfully run the command. For directories containing large numbers of binaries this is prohibitively cumbersome, and cannot be scripted. It does not seem to be possible (or at least documented) how to add an exception using spctl for something that is not an .app, although clearly such exceptions can be created via the graphical tool.