What is the best practice to apply a note inside a data table?

Example Scenario: As a user I need to update multiple data columns in a single row in but notes are necessary so that other users will know the reason.

So what do you think is the best practice?

My thoughts are: 1. A button(modal to add noted, 2. An action column with item saying "add notes", or (your idea).

Let me know if you have any questions

Thanks, Edwin