The real cost of an agent run is not the tokens. It's the hour you spend wondering why the tool call happened at all. Free model access and a free server lower the first cost, not the second. Without a trace loop, free tokens just let you fail faster.
The latest AI debates keep circling the same question: what do you do while the model codes? The answers usually involve code review or waiting. Neither works if you can't see what the model actually did. Agent summaries are claims, not logs. A tool call that inserted a file is a fact. The gap between claim and fact is where regressions hide.
That's why my debugging loop starts with traces. Every run logs each tool call, its arguments, its result hash, and a timestamp. Then I diff two traces and look for changes that should not have changed. This is not new. But doing it on a free server with free tokens changes the economics enough to make it the default.
Disclosure: This article was prepared as part of MonkeyCode's product outreach. MonkeyCode currently offers 10 million free tokens and a free server option, which is enough to run and trace a small regression suite for a week of experiments. I used that to set up the loop you see below.
