Skills that constrain how the agent works, so results survive a second look.
Jesse Vincent (obra) / test-driven-development
Because the failing test is the only thing that proves the agent understood the request.
Matt Pocock / tdd
Two good options, and installing both is the one clear mistake.
Jesse Vincent (obra) / systematic-debugging
A cause you can name, and a reason to believe the bug is actually gone.
Jesse Vincent (obra) / verification-before-completion
By making evidence, not confidence, the condition for finishing.
Matt Pocock / grill-me
The plan you cannot defend out loud is the plan that will fail in week three.
Anthropic / discernment-nudge
Two or three questions at the end, aimed at the parts most likely to be wrong for your situation.