Not the person you're replying to but yes, sometimes I do tell the agent to remove the cruft. Then I back up a few messages in the context and reword my request. Instead of just saying "fix this crash", or whatever, I say "this is crashing because the string is empty, however it shouldn't be empty, figure out why it's empty". And I might have it add some tests to ensure that whatever code is not returning/passing along empty strings.