verify

verify is a skill for Claude Code from SethGammon/Citadel. It costs 60 tokens per session (1,152 once invoked), scanned B, original, MIT.

A self-test for the coding system's hooks, which are automatic actions that run around tool calls such as writing files or running commands.

In plain words
What is it for?
Use it after installing or changing the hook system, or when tools seem slow or an expected quality check is not running.
Why use it?
It shows whether those automatic actions fired correctly and whether they recorded errors or timing information.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter. Also seen: reads .claude/ paths; mentions Codex.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is → Verify hooks are installed: node scripts/verify-hooks.js.

Part of the citadel plugin — 48 skills, 7 agents, 2 MCP servers shipped together

Good fit Use it after installing or changing the hook system, or when tools seem slow or an expected quality check is not running.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/SethGammon/Citadel
agentmods
npx agentmods add skills/sethgammon/citadel/verify

Made for: Claude Code.

Or install citadel, the plugin that ships this one along with the rest of its 48 skills, 7 agents, 2 MCP servers.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for verify

README.md
[![agentmods](https://agentmods.dev/badge/skills/sethgammon/citadel/verify/github.svg)](https://agentmods.dev/skills/sethgammon/citadel/verify)
Your own site
<a href="https://agentmods.dev/skills/sethgammon/citadel/verify"><img src="https://agentmods.dev/badge/skills/sethgammon/citadel/verify/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for verify

Your own site · 80×15
<a href="https://agentmods.dev/skills/sethgammon/citadel/verify"><img src="https://agentmods.dev/badge/skills/sethgammon/citadel/verify.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,152 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 2 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Tool Misuse · line 61
    Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).
    Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
  • high Agent Snooping · line 96
    Skill reads from agent configuration directories (.claude/, .codex/, .gemini/). These directories may contain API keys, personal settings, and other credentials that the skill has no legitimate need to access.
    Fix: Remove all code or instructions that access agent configuration directories (.claude/, .codex/, .gemini/). If configuration values are needed, pass them explicitly as parameters or environment variabl
How audits are shown
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 5.1 $0.00060 $0.01152
Opus 5.5 $0.00024 $0.00461
Sonnet 5.5 $0.00012 $0.00230
Haiku 4.5 $0.00006 $0.00115

Measured 28d ago against content hash 90e2fd47bbb9, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade B, and why

verify 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 28d 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.

→ Check settings.json: cat .claude/settings.json | grep PostToolUse
skills/verify/SKILL.md · 144 lines

How it starts

The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/verify — Hook Pipeline Self-Test

Use this when:

  • Hooks were recently updated and you want a live sanity check
  • Something feels wrong (tools seem too slow, quality-gate not firing)
  • After installing Citadel in a new project

Protocol

Step 1: Baseline

Read the current telemetry state:

.planning/telemetry/hook-timing.jsonl  → count lines (baseline_timing)
.planning/telemetry/audit.jsonl        → count lines (baseline_audit)
.planning/telemetry/hook-errors.log    → size in bytes (baseline_errors)

If telemetry directory doesn't exist, note it (init-project may not have run).

Step 2: Exercise hooks

Run these tool calls in sequence. Each exercises a different hook:

  1. Write a temp file at .planning/verify-temp.ts:

    // citadel verify probe
    export const verifyProbe = true;
    

    → Exercises: PreToolUse (protect-files, governance), PostToolUse (post-edit)

  2. Edit the same file — change true to false: → Exercises: PreToolUse (protect-files, governance), PostToolUse (post-edit)

  3. Bash a harmless read command: echo "verify-probe" → Exercises: PreToolUse (governance)

  4. Read the temp file back → Exercises: PreToolUse (protect-files — should allow, it's not .env)

  5. Delete the temp file: rm .planning/verify-temp.ts or equivalent → Cleanup

Step 3: Check side effects

After all tool calls complete, read telemetry again:

Check Expected Result
hook-timing.jsonl grew +2 or more lines (Write + Edit post-hooks) PASS/FAIL
audit.jsonl grew +3 or more lines (Write + Edit + Bash pre-hooks) PASS/FAIL
hook-errors.log unchanged same size as baseline PASS/FAIL

Step 4: Report

Output a results block:

=== HOOK HEALTH CHECK ===

hook-timing.jsonl:  +N lines  [PASS / FAIL]
audit.jsonl:        +N lines  [PASS / FAIL]
hook-errors.log:    no errors [PASS / FAIL — N new errors]

HOOK HEALTH: PASS

Or if any check fails:

HOOK HEALTH: FAIL

Failing checks:
- hook-timing.jsonl did not grow: PostToolUse hooks may not be firing
  → Verify hooks are installed: node scripts/verify-hooks.js
  → Check settings.json: cat .claude/settings.json | grep PostToolUse

- audit.jsonl did not grow: governance hook may not be firing
  → Check: node hooks_src/governance.js <<< '{}'

Read the full file on GitHub · 144 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. 28d ago Changed 90e2fd47bbb9
  2. 1mo ago First seen · 144 lines · 60 tokens per session scan B dd52b53b4120

Subscribe to this mod's changes

verify is a skill published in the GitHub repository SethGammon/Citadel (925 stars, last pushed 2d ago), licensed MIT. It adds 60 tokens to every session and 1,152 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-30.

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