`[2026-07-23→25]` **Worldtree #376 config-divergence arc — wyrd grant fixed, drift guard demoted, per-instance config ruled BY DESIGN.**

**Trigger.** wyrd-dev needed `session.history.write` on the DEMO Worldtree (operator-approved) — add `wyrd-dev` to the `session-history-write-ratatoskr` policy rule. Attempting it surfaced that the demo runtime `/opt/worldtree/config/policies.yaml` (mtime Jul-17) had **silently diverged from the repo** — missing whole rules, not a faithful copy of any revision. Refused to hand-edit a divergent authz file on a managed box; worldtree-dev prescribed a **wholesale replace** with `main@55f3fde`. Executed (backup → replace → `docker restart worldtree-worldtree-api-1` same-image → health-gate → verify) — grant live, demo policies at parity. **This was the ONE genuine bug of the arc:** a demo-intended grant that wasn't ON demo.

**Drift guard (#376).** worldtree-dev shipped a startup guard (b131/`62b85e3`) that hashes mounted config vs the image's baked copy, logging `CONFIG DRIFT (#376)`. First reading found MORE drift: `model_roles.yaml` on both instances + personal `policies.yaml`. Captured the three runtime-vs-baked diffs (read-only) → all had **runtime-only content** (personal's `agent_architect` role + `ratatoskr-affect-full-allow` rule — live-bridged, ahead of repo). The guard's STOP-on-runtime-only rule earned its keep: a blind "sync to repo" would've deleted legitimate per-instance config.

**Operator ruling (2026-07-25 — the reframe).** Worldtree will run dozens-to-hundreds of instances at v1, each configured for its env. **Per-instance config deltas are the DESIGN, not rot; back-streaming to the canonical repo doesn't scale.** Everything stood down: demo model_roles normalize withdrawn, personal sync cancelled, post-mortem dissolved, `.bak` deleted. Guard demoted b132/`ad596b5` from ERROR alarm to INFO `CONFIG BASELINE (#376)` breadcrumb (WARNING only for a mounted file *entirely absent* = breakage-adjacent). Breaking-change protection stays in `core.config_validator`'s boot gate.

**infra-ops watcher — built then retired same day.** Wired an off-box `wt-drift-watch` (systemd --user timer on nh3-dev, alerts worldtree-dev on new `CONFIG DRIFT` startup lines) — then RETIRED it per the ruling (the error line is going away). Lesson banked in auto-memory `reference_worldtree_perinstance_config`.

**Governance notes worth keeping:**
- The auto-mode guard **blocked** a peer-green-lit (worldtree-dev) config replace on the managed demo box because there was no *operator* consent for that specific change — correct: a config-mutation+restart on shared infra needs the operator's yes, not just a peer's. Surfaced it; the operator later stood the whole thing down. Good governance on both ends.
- This arc is the direct evidence base for the [[2026-07-25-infra-ops-wt-config-repo]] decision (infra-ops owns config-as-code so live-edits stop being untracked).
