What we do not let it near, written down

A scope decision recorded as a rule, because a rule can be reviewed and a feeling cannot.

## Where model assistance is not used

- authentication, authorisation, session handling
- anything that constructs a query
- cryptographic operations, including signature
  comparison
- database migrations
- the deploy pipeline

## Why these
The first three because a plausible-looking mistake is
a vulnerability. The last two because a mistake is not
reversible by a redeploy.

## Review: 2026-03

The list is short and it is the shape that matters — two categories with a stated reason each, rather than a general caution nobody can apply. It is also unenforceable, which is worth admitting: it is a norm the team agreed to, checked by review, and the review date is what stops it becoming folklore.