Know what your agents did.
Your agents work while you sleep.
In the morning you want one answer: what did they do?
An AI agent activity log gives it to you. It is a plain record, one line per action.
You can read it in a minute. This guide shows how to keep one.
1. A record beats trust
You can trust an agent and still want to see its work. That is what an audit log for AI agents is for.
A record lets you check without asking.
It turns "I think it did that" into a line you can read.
Keep it plain, so you will actually open it.
2. One line per action
Each line answers three questions: what, when, why.
What the agent did. When it did it. Why it chose to.
Here is a made up example of an activity log:
06:02 Sent the weekly summary. It was due this morning.
06:15 Moved two items to done. Both were finished.
06:40 Asked for a decision. The choice was outside its job.
Three short lines. You know the morning at a glance.
3. Choose where the log lives
Put the log somewhere the agent can add to but not change.
That is a practice you choose, not a guarantee.
It keeps the record in order and keeps each line as it was written.
Decide this on day one, before the first entry.
4. Read it on a schedule
Set one daily minute for the log.
Same time, same place, every day.
You are not hunting for trouble. You are confirming the day went as planned.
A habit you keep beats a review you plan to do someday.
5. The log is history. The handoff note is state.
These are two files with two jobs.
The log says what happened. The handoff note says what is open and what comes next.
Mixing them makes both harder to read.
For the second file, see the guide on agent memory between sessions.
6. Mark who decided
Note on each line whether the agent decided or you did.
When an agent asks you for a call, log your answer next to it.
Then the record shows the whole chain, from request to decision.
For the decision side, see the guide on agent approvals.
7. Check it
Pick one action from the log. Trace it end to end.
Find the thing itself: the file, the page, the message.
Does it match the line? A log tells you what the agent says it did. Looking at the thing confirms it.
Do this on a schedule, and the log stays honest.
