[pure_simplicity]

Thanks for that! It's not what I'm looking for, but it's good to know about. I really need it to be a CLI application that takes text as in put and produces an image as output.

[tonerow]

https://flowchart.fun doesn't have all the capabilities of UML diagramming for instance, but it is text->diagram conversion with a very simple syntax

[pure_simplicity]

This is not quite what I'm looking for. It needs to be CLI based so it can work with local markdown files in a way that can be easily automated. Also this website isn't tailored for visualizing a database schema, so to repurpose it for that use case requires significant effort. Looking at DBeaver's ER Diagram should like the OP in this response thread suggested should give you a good idea of how I want things to look.

I may have found what I'm looking for from a different top level answer though. Thanks for your contribution.