Synthetic bug-fix probes for AGENTS.md files
Repository teams using coding agents should add a small tuning job for their AGENTS.md or equivalent repository guidance. The job can generate synthetic bug-fix tasks, run the agent against them, record where the instructions sent it to the wrong subsystem or missed the right test command, then edit the guidance file under a size cap.
Probe-and-Refine gives a concrete pattern: 10 synthetic bug-fix probes per iteration, 3 to 5 iterations per repository, and a final guidance file reused by the coding agent. On 500 SWE-bench Verified instances, the refined guidance reached a 33.0% mean resolve rate, compared with 28.3% for static guidance and 25.5% with no context. The gain came mainly from producing evaluable patches more often, which fits the common maintainer pain: the agent wastes its budget in the wrong files or follows stale local habits.
A cheap first version is a nightly job on the top repositories where agents already open drafts. Track whether the agent reaches an evaluable patch, which commands it ran, and which guidance lines were used or contradicted. Keep the output short enough for every run to read, and require a human review for guidance edits that change release, security, or data-migration steps.