Activity is the record of what a run actually did.
What it shows
Each stage, in order: what it set out to do, what it read, what it produced. Enough to audit a conclusion rather than take it on trust.
Asking about the work
You can ask questions of the run itself — why it concluded something, what it considered, why it chose one surface over another. It answers from what it did, not by redoing the work.
This is usually faster than re-reading the output when you want to know whether to believe it.
When to use it
- A number looks wrong and you want its provenance
- A conclusion surprises you
- You are presenting the work and need to defend it