Record decisions with their reasons
"Use the existing parser" is less helpful than explaining which behavior it already handles and where it lives. Include the files inspected, the checks performed, and the assumptions that remain. Keep the note short enough to read before opening a new session; a raw conversation transcript usually hides the useful decisions.
Refresh the note when you return
Check whether the repository state has changed since the note was written. A teammate may have changed the same area, or your local edits may have moved forward. Ask the assistant to verify the relevant references before continuing. Do not assume that a new session retains old context or that remembered details are still accurate.