RatatoskrSkill: Instructions file for Claude Code

RatatoskrSkill

Purpose

This repository exists solely so the author can develop and version the ratatoskr skill. The canonical file is skills/ratatoskr/SKILL.md — people install it as a Claude Code plugin (or copy that one file into their agent's skill dir). Nothing in this repo (CLAUDE.md, CHANGELOG.md, README.md, CI, etc.) may affect the skill's mechanics. All behavior must be self-contained in skills/ratatoskr/SKILL.md.

Ratatoskr is an add-on in the Yggdrasil family: it attaches to the agent, not to the graph, and works alone. It is the communication layer — the courier that keeps the agent talking to the user in plain words, never in code. It governs how the agent communicates on every turn, not how the work is sequenced. The family's core is Jarl (the loop), Yggdrasil (the law: the architecture graph and the rails), Grain (the survey: the first graph, mined from a repository's own code and history) and Horde (plans a mission onto the law before anyone writes and lands every change through a gate, on Jarl's loop, with Grain in the architect's hands); you start at the step where it hurts. Ratatoskr, Urd and Researcher are the three add-ons beside the core, each with no dependency of its own.

Plugin scaffolding

This repo is installable as a Claude Code plugin and as a GitHub Copilot CLI plugin. Layout mirrors the convention used by sibling repos (e.g. UrdSkill, ResearcherSkill):

• .claude-plugin/plugin.json — plugin manifest (name, version, description, keywords). version here MUST match the latest released version in CHANGELOG.md and is bumped together with it.
• .claude-plugin/marketplace.json — single-plugin marketplace listing for Claude Code, so the repo can be added via /plugin install ratatoskr@ratatoskr-marketplace.
• .github/plugin/marketplace.json — single-plugin marketplace listing for GitHub Copilot CLI (Copilot reads this path), so the repo can be added via copilot plugin marketplace add krzysztofdudek/RatatoskrSkill then copilot plugin install ratatoskr@ratatoskr-marketplace. Mirrors the Claude listing but additionally carries version, a skills array (./skills/ratatoskr), and a hooks field pointing at ./hooks/copilot-hooks.json (the Copilot-format session-start hook). Its plugin version MUST be kept in lockstep with plugin.json.
• .codex-plugin/plugin.json — plugin manifest for OpenAI Codex CLI (Codex reads the plugin manifest only from .codex-plugin/). Bundles the skill via "skills": "./skills/"; Codex discovers the marketplace from the existing .claude-plugin/marketplace.json (its legacy-compatible path), so the repo installs via codex plugin marketplace add krzysztofdudek/RatatoskrSkill then codex plugin install ratatoskr@ratatoskr-marketplace. Its version MUST be kept in lockstep with plugin.json. Codex needs no hook wiring of its own: it auto-discovers the default hooks/hooks.json, reuses Claude's SessionStart/hookSpecificOutput schema, and sets CLAUDE_PLUGIN_ROOT for compatibility, so the bundled Claude hook fires under Codex unchanged.
• .cursor-plugin/plugin.json — plugin manifest for Cursor (single-plugin-at-root: manifest at the repo root, no Cursor marketplace file; components are auto-discovered, so skills/ratatoskr/ is picked up automatically). Installed locally via ~/.cursor/plugins/local/ or published to the Cursor Marketplace. Carries a hooks field pointing at hooks/cursor-hooks.json (the Cursor-format session-start hook). Its version MUST be kept in lockstep with plugin.json.
• hooks/ — session-start activation hooks, one per platform we integrate with. Activation-only: each injects a short instruction so the agent applies the skill from the first turn and re-asserts it after compaction; they encode no rules of their own, so the self-containment rule holds — all behavior still lives in SKILL.md. One shared script, hooks/ratatoskr-session-start.sh, emits the right stdout envelope based on its $1 argument (claude/codex → hookSpecificOutput.additionalContext; copilot → flat additionalContext; cursor → snake_case additional_context). The per-platform configs: hooks/hooks.json (Claude SessionStart, also auto-discovered by Codex), hooks/copilot-hooks.json (Copilot sessionStart, wired via the .github/plugin/marketplace.json hooks field, uses ${PLUGIN_ROOT}), and hooks/cursor-hooks.json (Cursor sessionStart, wired via the .cursor-plugin/plugin.json hooks field). The message lives once, in the script. com.github.copilot/hooks/hooks.json is the same Copilot hook for the portable layout (Copilot reads it once the root plugin.json is there) and must stay identical to hooks/copilot-hooks.json.
• skills/ratatoskr/SKILL.md — the canonical skill body. Editing this file IS editing the skill.