A decision occurs when the workflow chooses a consequential next state: use a source, select a tool, refuse a request, seek approval, execute an action, retry, stop, or recommend release. Logging every token is unnecessary; logging material transitions creates a more understandable record.
Each event should state the decision type, work-item identifier, actor, timestamp, available context references, applicable policy, authority state, selected outcome, and reason category. The reason category can be structured, such as permission denied or evidence incomplete, with a concise human-readable explanation.
The explanation should describe observable factors rather than invent hidden reasoning. For example, a refusal can say that the requested account fell outside authorized scope and cite the policy result. That statement is reviewable; a narrative about what the model internally believed is not required.
When a model provides a rationale field, treat it as generated output that may help review, not as a privileged account of causation. The record should anchor important claims in observable inputs, policy evaluations, and actions so investigators can challenge the explanation against evidence.