Record the reasoning, not only the result
A governed workflow retains what it saw, which rule it applied, who approved the step and when. That record is what allows the organization to answer a question months later without reconstructing the event from memory.
Carry permissions all the way through
Access rules that exist in the source system must survive retrieval, summarization and display. A summary that reveals content the reader could not otherwise open is a control failure, regardless of how accurate it is.
Abstention is a control
The most valuable behaviour in a governed system is declining to answer when the evidence is insufficient. Designing the abstention threshold, and measuring how often it triggers, tells you more about reliability than any accuracy figure quoted in isolation.