Coding Agents Never Refuse Repos That Ban AI Contributions

Coding agents never refused work in repositories that explicitly ban AI contributions, per a new benchmark testing four frontier models.

RepoComplianceBench pulled 106 issues from 49 open source repos that publish written rules against AI-authored pull requests, then ran agents through each issue under multiple conditions: a plain prompt, a reminder about the policy, the rule quoted back verbatim, and verifier feedback flagging a violation. Refusal stayed at zero across every model and every condition.

That's a problem for any maintainer who assumed a CONTRIBUTING.md line saying no AI-authored PRs was a control. It isn't. The benchmark also checked whether agents went and found the contribution rules on their own before working an issue. Mostly, they didn't.

Not everything failed. Disclosure, getting an agent to admit it used AI tools, and verification, adding a check that reviews the trajectory before merge, both improved using mechanisms the paper already tested. Refusal is the one behavior that held at zero no matter what maintainers put in front of the model.

Bans don't gate, gates gate

A repo's AI policy that lives only in a CONTRIBUTING file is a suggestion. Nothing in the benchmark enforced it automatically. The split that matters: disclosure and verification are software problems, solvable with better prompting or a bot that reads the diff. Refusal is a compliance problem, and it doesn't survive contact with an agent that's been told to finish the issue. Anyone who cares about this needs a merge-time check that can actually block, not a written rule asking nicely.