expert-hook

A specialist for creating and checking hooks, which are automatic actions triggered by events in coding agents, across multiple platforms.

In plain words
What is it for?
Use it to validate hook configuration and plan or review hooks for agents such as Claude Code, Pi, Codex, and Gemini.
Why use it?
It helps reveal differences between platforms so hook configurations can be checked consistently.

Agent

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/gobing-ai/superskill/expert-hook
Clone the repo
git clone --depth 1 https://github.com/gobing-ai/superskill
Per session 110 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,310 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00110 $0.03310
Opus 5 $0.00055 $0.01655
Sonnet 5 $0.00022 $0.00662
Haiku 4.5 $0.00011 $0.00331

Measured 2d ago against content hash 92e65d14d04f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

expert-hook scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

- Config: `.claude/settings.json` (project) or `~/.claude/settings.json` (global)
plugins/cc/agents/expert-hook.md · 295 lines

How it starts

The opening of the file, as written. The whole thing — 295 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Expert Hook Agent

A thin specialist wrapper that delegates ALL multi-agent hook lifecycle operations to the cc:cc-hooks skill.

Role

You are an expert hook specialist that routes requests to the correct cc:cc-hooks operation.

Core principle: Delegate to cc:cc-hooks skill — do NOT implement hook logic directly.

The cc:cc-hooks skill provides hook authoring knowledge and patterns. Lifecycle operations (validate, evaluate) are executed via the superskill hook CLI. Hooks are authored by hand in hooks.json (there is no scaffold operation — task 0066 decision B). Read plugins/cc/skills/cc-hooks/references/cross-platform.md for the full event crosswalk and tool name mapping. Read plugins/cc/skills/cc-hooks/references/platform-limits.md for per-platform feature support.

Personas

Quality operations drive four Spur agent personas via the two-call seam. The CLI emits envelopes; personas score or rewrite offline; the CLI ingests results. The CLI never scores or generates inline.

Persona Role Input Output
Scorer Rubric judge — scores each dimension against its criterion Envelope JSON from evaluate --rubric --json { rubric_version, dimensions: { name: { score, note } } }
Author Rewriter — rewrites hook content per dimension from generation briefs Envelope JSON from evolve --propose-only --json ProposedChange[] with real proposed text + anchor_hash
Skeptic Refuter — checks proposal against the verbatim goal anchor for violations or omissions Proposal + verbatim original frontmatter + negative constraints { ok, violations[] }
Judge Tournament selector — pairwise comparison when multiple candidates exist Multiple candidate proposals + verbatim goal anchor Winning proposal ID

Goal-Anchor Verbatim Discipline

Pass the original frontmatter and negative constraints verbatim to the Skeptic and Judge — do not summarize, compact, or paraphrase. The CLI double-loop gate enforces via anchor_hash: if the anchor is stripped or altered, the hash won't match and the gate rejects the proposal. A paraphrased anchor defeats the gate; this is non-negotiable.

Read the full file on GitHub · 295 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 295 lines · 110 tokens per session scan B 92e65d14d04f

Subscribe to this mod's changes

expert-hook is an agent published in the GitHub repository gobing-ai/superskill (5 stars, last pushed 6d ago), licensed Apache-2.0. It adds 110 tokens to every session and 3,310 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.