In practice.
What the record is for when someone asks what an agent did, and how long-running agents get through a crash.
When someone asks
Answer the security review.
A bank or insurer asks how you record what your agent does, who can see those records and how long you keep them. Show them the journal. With Pragmatic Server, in design-partner preview, also show your retention rules, your access log and an evidence file they can verify themselves.
Reconstruct an incident.
Replay the run that went wrong, step by step, with the model responses it actually received. No re-sampling, and no guessing what the model might have said. Mark the agent with @pragmatic.durable and replay refuses code that has changed since, so you know you are looking at the same program. Without it, replay stops at the first step that differs from the record.
Evidence for a dispute.
A customer says the agent did something it should not have. Export that run: what was asked, what the model answered, which tools ran and in what order. With independent timestamps (Pragmatic Server, in design-partner preview), the evidence also shows the record existed by a given time, and the other side can check it without trusting you.
Retention and erasure requests.
Keep each kind of run as long as your policy says, hold runs for litigation, and erase one person’s data when they ask under GDPR or a similar law. The content is removed, the fingerprints stay, and the rest of the record still verifies. Retention, holds and erasure are part of Pragmatic Server, in design-partner preview.
Agents that run for days.
Long-running agents survive restarts, deploys and machine failures, then resume where they stopped. A run that dies nine hundred steps in does not pay for nine hundred model calls again. It continues at step nine hundred and one, and tool calls that already finished are not repeated.
Your environment, your data. The runtime is a library and journals are files on your own disk. Pragmatic Server, in preview, also runs in your environment, so records stay in the region you choose.