You're not entitled to know what specific tools were used to produce something, generally speaking.
In the absence of such an entitlement, not volunteering to disclose the tools used is not fraud.
Don't think calling a PR written by AI is the same thing as using a "tool". If code is largely generated by AI means that AI was an author and not you with some tool.
Don't think calling a PR written by AI is the same thing as using a "tool". If code is largely generated by AI means that AI was an author and not you with some tool.