Practical guidance for teams moving from "prompt tuning" to governed model release operations.
Why behaviour validation needs deterministic inputs, stable artefacts, and versioned release criteria.
How baseline-versus-candidate comparisons reduce ambiguous regressions and speed reviewer decisions.
The most expensive failures usually come from action surfaces, not wording. Tool traces need first-class visibility.
Release quality for LLM systems is measured by repeatability. If teams cannot rerun the same probes and compare output changes deterministically, they cannot make defensible release decisions.
Diffs should be stored as artefacts with decision context. They are not diagnostics alone; they are the review object used to approve, block, or waive changes.
Any expansion in callable tools should be treated as a material behavioural change. Governance requires visibility into tool permissions, inputs, and side effects.