Custom command including multiple fixed files?

From the documentation at Commands - Sourcegraph docs and from experimenting it does not seem to be possible to create a custom command with more than one specific file as context? I know I can use a directory or the more “dynamic” options, but I would like to specify an exact set of files.

Also, it was unexpected that the prompt is sent immediately and the LLM responds without asking for an initial command, but I guess that make sense if for things like: “fix typos and improve grammar in the comments of the selected code”.

It’s easy to “program” by asking the LLM to wait for the first input before responding though.