Am I right?
Do you find that having some kind of intelligent agent based analysis on PR and spec is going to help you?
Previously i worked on a on-premise HR solution which had lots of problems with technical debt. I think even in this case it wouldn't have helped to have some kind of tool, since the problem was not really to know what to do but "how" to do it.
We approached the problem by extracting domain-isolated "microservices" (i.e. separate modules). This worked quite well, but had the usual drawback of being "only" technical, not helping the users in any way. Bad from the POV of a manager :-)