Virality of AGPL when using CLI application
Apologies if this is clearly answered in the sub already - I looked, but came up short.
Bundled with my Linux (raspbian) installation is the gs (Ghostscript) utility. I'm aware they offer dual-licensing, one of which is AGPL.
My understanding of the spirit of the license is that it ensures that any derivative work (including linking) is virally licensed. What I'm having trouble with is understanding whether shell-spawning from code (for instance, if I had an Express.js API interface that, when invoked, used a shell command to invoke gs) constitutes "linking" from the license's perspective.
I do see someone on the internet tried to answer this same question, but it didn't sound 100% confident. In the above example, does the API itself now have AGPL obligations? The API's consumers? Does the calculus change if the API is on an intranet vs. public-facing?