The habit before an edit is no longer “dump the repo into the chat.”

prepare_change (CLI: prism prepare) returns:

a pack of files — path, symbols, why, map-token weight
reuse — helpers that already do the thing you described
House Style — three exemplars (canonical, recent, older) for route-handler, screen, colocated-test, or worker
notes — a remember you saved, an ADR, a WHY: comment
a work order — in-scope, off-limits (generated/vendor), needs-sign-off

Paths and names only. A unique string that exists only inside a fixture file body must not appear in the JSON.

If two symbols share a name, Prepare returns candidates. It does not pick. If nothing to reuse exists, the list is empty — do not invent a helper. If the stack is unknown, House Style is empty — do not invent a style.

The work order is advisory. The IDE hook that can veto a write stays off until an Accepted ADR arms it.

When Iris has an index, a Dispatch job gets that pack in its prompt. The worker still has no shell and still does not get file bodies.

See Prepare a change.

1.12.0 — Prepare: ask what to open