@gromero thanks for initiating this conversation. I think this is an important topic to consider as the TVM contributions are growing. Having a guideline that the community has accepted is important so the reviewers could use as a reference to make decisions. But more importantly, I totally agree with @driazati that without some sort of tooling it is very challenging to enforce those guidelines and it would also put too much responsibilities on reviewers.
Looking briefly at @manupa-arm’s suggestion, I think Gitlint seems to be a good option to adopt in TVM.
Regarding the guideline/tooling, in my experience I see that people spend a good time on writing the PR description and usually PR description includes enough information to get a good understanding of the commit after merge. I wonder if there’s a way to add the PR description as part of commit message (or make it the commit message).