henkaten-council

henkaten-council

A Claude Code plugin that adds a continuous-improvement governance layer on top of any project managed by the trine-eval harness. The council detects change points (henkaten), audits autonomous decisions, manages a dynamic autonomy floor, and enforces the andon protocol across sprints.

A note on the name. henka (変化) means "change"; henkaten (変化点) is the specific Toyota Production System term for a "change point" — the concept this plugin is built around. The repo got the shorter henka-council for URL brevity, but the plugin identifier, the skill namespace (/henkaten-council:...), and every in-code reference use the full henkaten-council. The contraction is deliberate and documented in docs/phase-0-proposal.md. Internally the plugin also distinguishes henkaten (変化点 — passive, emerged) from henkoten (変更点 — active, deliberately initiated) on every change-point record, but uses "henkaten" as the umbrella name.

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What it Does

The henkaten-council plugin wires a council of specialized agents into the Claude Code skill system. Each sprint, the council:

1. Detects change points using 4M axis classification (Man/Machine/Method/Material)
2. Audits every correction with evidence citations and reversibility flags
3. Manages a dynamic autonomy floor that drops on consecutive sprint failures or repeated andon stops from multiple distinct originators
4. Delegates sprint evaluation to the trine-eval harness via /trine-eval:harness-sprint
5. Records all governance activity to append-only JSONL logs under .council/

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Prerequisites

• Claude Code ≥ 0.3.0
• trine-eval ≥ 0.3.0 installed and initialized in your target project (run /trine-eval:harness-kickoff first if the .harness/ directory does not yet exist)
• Git ≥ 2.30

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Install

Option A — Marketplace (Recommended)

This repository ships its own single-plugin marketplace manifest (.claude-plugin/marketplace.json). In Claude Code, add the repo as a marketplace, then install the plugin from it:

/plugin marketplace add ats-kinoshita-iso/henka-council
/plugin install henkaten-council@henkaten-council

Claude Code will fetch the plugin, auto-discover the skills and agents under skills/ and agents/, auto-register the hooks declared in hooks/hooks.json, and load CLAUDE.md automatically for all future sessions in the project.

Option B — Direct Path Install

Clone this repository and add it as a local marketplace:

git clone https://github.com/ats-kinoshita-iso/henka-council.git
/plugin marketplace add ./henka-council
/plugin install henkaten-council@henkaten-council

After installation, verify the plugin is active:

/plugin list

You should see henkaten-council in the output with status active.

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Hook Installation and Self-Check

The council's enforcement hooks must be registered with Claude Code's hook system before the council can prevent append-only log overwrites or enforce the reversibility policy. The hooks live in hooks/ (Bash, for Linux/macOS) and hooks/win/ (PowerShell, for Windows).

As of v0.1.2: hooks auto-register from hooks/hooks.json when the plugin is installed via the marketplace flow (Option A above). The kickoff skill's Step 1d.0 detects this case and the manual snippet below is then only a fallback — needed for direct-path installs on Claude Code builds that don't read plugin-level hooks.json, or for pure-PowerShell Windows hosts without bash.

When you run /henkaten-council:council-kickoff for the first time, the skill performs a hook installation self-check and refuses to proceed past Step 1d if neither auto-registration nor manual registration covers all four required hooks.

The full registration snippet is in skills/council-kickoff/SKILL.md under Step 1d.1 (Linux/macOS) and Step 1d.2 (Windows). The short version:

Add this hooks block to your target project's .claude/settings.local.json:

"hooks": {
  "PreToolUse": [
    { "matcher": "Write|Edit",
      "hooks": [{ "type": "command",
                  "command": "bash ${CLAUDE_PLUGIN_ROOT}/hooks/enforce-append-only.sh" }] },
    { "matcher": "Bash",
      "hooks": [{ "type": "command",
                  "command": "bash ${CLAUDE_PLUGIN_ROOT}/hooks/enforce-reversibility.sh" }] }
  ],
  "PostToolUse": [
    { "matcher": "*",
      "hooks": [{ "type": "command",
                  "command": "bash ${CLAUDE_PLUGIN_ROOT}/hooks/log-tool-call.sh" }] }
  ],
  "Stop": [
    { "hooks": [{ "type": "command",
                  "command": "bash ${CLAUDE_PLUGIN_ROOT}/hooks/session-stopped-marker.sh" }] }
  ]
}