sync

name	sync
description	Self-update — read the latest releases across the engine's whole surface (Anthropic, stack, services, practice), diff against the engine, adopt or propose
when_to_use	Use when self-updating the engine against upstream releases — reads the Anthropic/stack/services/practice release feeds per engine.json sync tiers, diffs findings against the engine, adopts mechanical wins, proposes the rest, and stamps sync dates. Triggers on: sync, what's new in claude code, refresh the engine, release sweep.
argument-hint	[anthropic|stack|services|practice|all] [--force]

Sync — the engine updates itself

Kun configures the best of what exists rather than rebuilding it — which only works if it always knows what exists. /sync is that loop, across four tiers. Anchor: .claude/engine.json → sync.

The keyword sync in natural conversation ("are we current?", "sync the engine", "anything new in Next.js?") routes here — no slash needed.

Tiers

Tier	Surface	Cadence	Stamp
anthropic	Claude Code CHANGELOG · platform release notes · anthropic.com/news	7 days	sync.anthropic
stack	Next.js · React · TypeScript · Tailwind · Prisma · shadcn/ui release surfaces	14 days	sync.stack
services	Vercel · Neon · GitHub · Figma changelogs	14 days	sync.services
practice	Agent-config craft: Anthropic engineering blog, AGENTS.md ecosystem, BMAD-method, high-signal community Claude Code configs	30 days	sync.practice

Exact URLs live in engine.json → sync.sources — when a source moves, fix it there, not here.

Steps

1. Decide scope

• No argument → every tier whose stamp is older than its cadence (or null = never synced). Nothing due → report per-tier freshness and stop.
• anthropic / stack / services / practice → that tier only.
• all → every tier. --force ignores staleness.

2. Fetch (parallel WebFetch; gh api for GitHub releases)

For each in-scope tier, extract only what is NEW since the tier's stamp and RELEVANT to the engine:

• anthropic — new tools, config surfaces (settings keys, frontmatter fields, hook events, .claude/* dirs), models, permissions/sandbox, autonomy/long-horizon features, plan/billing changes
• stack — new versions, breaking changes, deprecations, new idioms for the versions kun's products pin (Next.js 16, React 19, TypeScript 5, Tailwind 4, Prisma 6, shadcn/ui)
• services — platform changes that touch deploys (Vercel), databases (Neon), repo workflows (GitHub), design handoff (Figma)
• practice — agent-config patterns worth stealing: multi-agent methods (e.g. BMAD), CLAUDE.md/AGENTS.md conventions, skill/hook/workflow/subagent techniques

Sources of the form gh:owner/repo mean gh api repos/owner/repo/releases --jq '.[0:5] | .[] | {tag_name, published_at, body}' — cheaper and more structured than fetching release pages.

3. Classify each finding

Class	Meaning	Action
ADOPT-SAFE	Pure config/docs addition — no behavior risk, no spend, no team-workflow change	Apply now
ADOPT-DECIDE	Changes behavior, cost, dependencies, or how the team works — including any product version bump	/decide entry + GitHub issue (type:chore, label engine-upgrade); PushNotification Abdout if Type-1
TRACK	Real but not useful to kun yet	Deferred list in docs/CONFIG-BENCHMARK.md

Standing constraints veto adoption regardless of class:

• Subscription-only — nothing that requires usage credits or per-token spend (engine.json → billing)
• Main-only git — nothing that reintroduces branches/worktrees/PRs (.claude/rules/github-workflow.md)
• Anthropic-native — no third-party substitutes for anything Anthropic ships (docs/CONFIG-BENCHMARK.md)

Stack findings diff against reality, not memory: product package.json versions + the rule corpus (.claude/rules/<domain>/, since: frontmatter). A breaking change with no matching rule → write the rule (ADOPT-SAFE). A version bump for products → ADOPT-DECIDE, executed via /package.

3.5 Harness audit (on model releases only)

When the anthropic tier surfaces a new model (or a major Claude Code version), run the reverse pass: every rule, hook, gate, and fix-loop in the engine encodes an assumption about what the model couldn't do when it was written. Sample the highest-friction ones (fix loops with retry caps, mandatory verification passes, deny-list breadth) and ask: does the new model still need this scaffold? Propose removals as ADOPT-DECIDE — guardrails get retired, not just added. (Anthropic harness-engineering guidance, adopted 2026-07-10.)

4. Apply + record

1. Apply ADOPT-SAFE to canonical sources; regenerate plugins if any plugin source changed (bash .claude/scripts/build-plugin.sh)
2. Stamp each synced tier: engine.json → sync.<tier> = today; tier anthropic also updates sync.claude_code_version
3. Material adoptions → dated line in docs/CONFIG-BENCHMARK.md → Adoption log
4. Commit: chore(engine): sync <tiers> — <headline> + git pull --rebase origin main && git push origin main

5. Report

One table per synced tier — finding → class → action taken — then per-tier freshness ("anthropic 0d · stack 0d · services 12d · practice 21d").

Cadence

• Weekly: /weekly Monday plan runs /sync first (due tiers only — usually just anthropic).
• Session start: the captain flags any overdue tier and syncs before allocating.
• Event-driven: a release mentioned in conversation ("did you see the Next.js release?") → sync that tier now.

Exit gate

Every in-scope tier stamped today, every finding classified, ADOPT-SAFE applied and committed, ADOPT-DECIDE escalated with a durable record.