security-review

A security review command for the project’s current changes. It checks code against common protections for inputs, authentication, secrets, browser attacks, dependencies, and error messages.

In plain words
What is it for?
Use it to review changed files, assign findings a severity from Critical to Low, and receive a proposed fix for each issue.
Why use it?
It helps identify security weaknesses in newly modified files before they reach users or production.

Command for Claude Code

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 commands/erniker/understudy/security-review
Clone the repo
git clone --depth 1 https://github.com/erniker/understudy

Made for: Claude Code.

Per session 8 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 157 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. 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 $0.00008 $0.00157
Opus 5 $0.00004 $0.00078
Sonnet 5 $0.00002 $0.00031
Haiku 4.5 $0.00001 $0.00016

Measured 2d ago against content hash 45c0e93bc753, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

security-review scanned grade A with 0 findings 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

templates/.claude/commands/security-review.md · 23 lines

What it actually says

Act as the team's Security Expert. Review the current project changes.

Process:

  1. Analyze recent changes (modified or new files)
  2. Verify against the security checklist:
    • Input validation at every boundary
    • Adequate output encoding
    • Correct authentication and authorization
    • No hardcoded secrets
    • Error handling does not reveal internal information
    • Secure dependencies
    • CORS, CSRF, XSS protected
  3. Document findings with severity (Critical, High, Medium, Low)
  4. Propose fixes for each finding

If the architecture is documented in docs/decisions.md, use it to understand the threat model and expected security controls.

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 · 23 lines · 8 tokens per session scan A 45c0e93bc753

Subscribe to this mod's changes

security-review is a command published in the GitHub repository erniker/understudy (3 stars, last pushed 1mo ago), licensed MIT. It adds 8 tokens to every session and 157 once invoked, about $0.0000 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.