That’s not the state of LLMs today, nobody trains them for a specific use case, almost nobody fine tunes them either. You just have to give them some context and the means to gather more context (access to code in order to see the logs at source, access to logs themselves, etc.) - whatever you would have access to as a human debugging this.
> deep Jiras that require a lot of domain knowledge, bespoke testing tools, but maybe just a few lines of actual code changes
How do new hires onboard? Do you spend days of your own time guiding them in person, do they just figure things out on their own after a few quarters of working on small tickets, or are things documented? Basically AI, when working on a codebase, has the same level of context that a new hire would have, so if you want them to get started faster then provide them with ample documentation.