DIFFERENTIATION_PUBLIC_STANCE.md

Differentiation public stance

differentiation_check.py writes layer_f_note into every report:

Layer F validates local sensitivity and FD consistency; it is not a public autograd guarantee.

Public claims (allowed)

• Layer F is internal validation: scripts/differentiation_check.py, optional torch/jax toy probes, --shield-inter-sim on licensed hosts.
• tests/vendor/diff/ — engineering only, not product marketing.

Public claims (forbidden)

• Production shield autograd (enable_grad on the real shield QP).
• “Fully validated differentiable runtime shield stack” in README, decks, or release notes.

Promotion gate (future)

Do not change public narrative until all pass on licensed hosts:

1. Production-path autograd tests on shield objective
2. Autograd vs FD within declared tolerances
3. Stability around active-set changes
4. Maintainer milestone + explicit doc update

Until then: ROADMAP.md item 2 stays deferred.