- plan_init is now the ONLY plan tool: a mermaid 'graph TD' block parsed by a
constrained-subset parser (mermaid-plan.ts) with line-precise errors; the
seven mutation/tracking tools are gone by design (2026-09-03 design pass).
- Re-call plan_init = sanctioned wholesale rewrite; slugs are permanent.
- derivePlanStatuses (contracts/plan.ts): done = passed check tagged with a
quiz nodeId; current = open check's node else first topo-ready node — the
tracking the teacher no longer declares by hand.
- questionToolsFor(ctx) (tools.ts): the quiz schema chains a dynamic plan-
nodeId validation against the LIVE record — an invalid nodeId is rejected
at the call boundary and the teacher retries mid-turn, before any UI.
Static questionTools stay validator-less for the default path.
- Prompts rewritten for mermaid authoring + derived position.
- Out-of-lane surgical touches (flagged for master review):
src/core/question-core.ts (quizInputObject export + nodeId description),
src/core/contracts/plan.ts (derivePlanStatuses + doc).
Purely mechanical: src/core/contracts/{plan,graph,chat,jobs}.ts carry the
sections verbatim (graph = nodes + ledgers + extraction findings; jobs =
the async ack-and-steer protocol + tool results + demo bridge), and
contracts.ts becomes a re-exporting barrel so every existing import path
(@/src/core and ./contracts.ts) is unchanged.
Wave-2 lane ownership follows the split: the graph stream owns
contracts/graph.ts, the teacher stream owns contracts/jobs.ts — same-file
contract collisions between streams are structurally impossible now;
cross-domain schema changes go through master.