Persona-Execution Separation: An Architecture Pattern for Evolving LLM Agents under Execution Audit

**Persona-Execution Separation** places persona and execution in different trust domains joined by a governed contract bridge. Execution remains faceless and audited; summaries can return, while data bodies stay restricted unless a graded DLP exception applies.

For multi-user agents with frequent prompt or persona changes, keep stateful actions behind typed changes, approvals, DLP, and a stable audit anchor. Treat persona updates as untrusted presentation changes rather than execution-policy changes.

The evidence is a **one-month pilot** recording five decisions plus checks across **five model configurations**. The pattern is scoped to systems that jointly require persona churn, multi-user deployment, and execution audit.