If I'm logging into a server later to resolve an issue, one thing I will probably check is the command history. If you open a file with "vi", how do I know that

If I'm logging into a server later to resolve an issue, one thing I will probably check is the command history. If you open a file with "vi", how do I know that you only looked at it, and did not make any changes to it? When I see "less" in the command history, I know for certain that it was a read-only operation.