I could perhaps see more value for this, at this level of capability, in writing test cases, in cases where the project is setup in a way to let them be run and get feedback.

This would be useful in cases where test coverage is incomplete, maybe for auto-discovering/confirming bugs, and would really be needed if it's trying to fix bugs itself, especially if one dared let it commit bug fixes - would want to know that the fix worked and didn't break anything else (regression test - run other test cases too).