Evidence-first authority page
Audit Logging for AI Agent Actions
What a production AI agent's audit log should capture, beyond simple request/response pairs, to support incident investigation.
Direct answer
A complete AI agent audit log records not just the final response but every tool call made, the reasoning or intermediate steps that led to each call, and which specific model version handled the request — without all three, investigating why an agent took a specific action after the fact becomes guesswork rather than a reconstructable trace.
Last reviewed 2026-09-17
This page remains noindex while its page-level source receipts are completed and verified. It is available for review, not presented as publication-ready authority.
What to log beyond the final answer
- Every tool call: which tool, what arguments, what result was returned.
- The model version used, since behavior can shift across model updates.
- Any intermediate reasoning steps, if the agent architecture exposes them.
Why request/response logging alone fails during an actual incident
When an agent takes an unexpected or harmful action, the question that actually needs answering is why — what information it had, what tool calls it made, and what led to the specific decision, not just what the final output was. A log that only captures input and output leaves a gap in the middle that makes root-causing a genuine incident far slower, and in some cases impossible to reconstruct after the fact.
Recording the specific model version matters because model providers routinely update models behind the same API endpoint or model name, and behavior can shift subtly between versions — an incident review that doesn't know which exact model version handled a request is working with an incomplete picture of what actually happened.
What a usable audit log needs beyond just capturing data
- Retention long enough to support investigation of an issue that surfaces weeks after the fact, not just the last few hours.
- Searchability by user, session, or specific tool call, so an investigation doesn't require manually scanning raw logs.
- Clear ownership of who can access the log, since it may contain sensitive information about what users asked and what data tools returned.