Audit Trail (Agent)
When something goes wrong after the fact, only one question matters: what actually happened. An audit trail is an agent's answer — a durable, append-only record of every action it took, what it was working from, and who allowed it.
What gets recorded
The entries are written as the run proceeds, never reconstructed afterwards:
- Each tool call — the name, the arguments, the result, the timestamp.
- The identity the agent acted under, and the permissions that identity held.
- Every human decision: an approval gate cleared, a confirmation declined, an escalation raised.
- The prompt and model version behind each step, so behaviour can be traced to its cause.
Why accountability needs its own record
Tracing and auditing look similar and serve different masters. A trace exists to help an engineer debug latency and failure, and it is perfectly acceptable for it to be sampled, truncated or dropped. An audit trail exists to answer a customer, a regulator or a security review months later, which makes completeness, retention and tamper-resistance the properties that matter — write-once storage, no editing, no gaps.
What breaks without it
An agent that issued the wrong refund or emailed the wrong client leaves nobody able to say whether it was misinstructed, misconfigured, or steered by text hidden in a document it read. The incident becomes unprovable in both directions: you cannot demonstrate fault and you cannot demonstrate innocence. That is usually what stops an autonomous system from being allowed anywhere near regulated work.
An audit trail is the durable, ordered record of what an agent did — every prompt, tool call, argument, result and approval decision, timestamped and attributable to a specific run. It turns an opaque autonomous loop into something reviewable after the fact: incidents can be reconstructed, a harmful action traced to the step that authorised it, and cost or policy breaches attributed. Without it, accountability ends at the final answer.
Think of a company credit card. You can use it without asking permission each time, but every charge appears on a statement with the date, the amount and the shop — so a questioned purchase can be checked later.
An audit trail is that statement for software that acts on its own. Every action the system takes — the file it changed, the email it sent, the refund it approved — gets written down as it happens, and the record cannot be edited afterwards.
It matters because nobody is watching each step. When something goes wrong, the trail is the only way to know what the software actually did.