sanity-check-reviewer

A command that audits newly written or changed code for security vulnerabilities, performance problems, and code-quality issues before it is merged.

In plain words
What is it for?
Use it to inspect changed files, understand their context, check authentication and user-input handling, and review critical code paths before creating a pull request.
Why use it?
It provides a second review focused on risks that ordinary code review may miss, such as injection attacks, weak access checks, or inefficient code.

Command

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/ebay/claudeplugins/sanity-check
Clone the repo
git clone --depth 1 https://github.com/eBay/claudePlugins
Per session 34 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,593 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 $0.00034 $0.01593
Opus 5 $0.00017 $0.00796
Sonnet 5 $0.00007 $0.00319
Haiku 4.5 $0.00003 $0.00159

Measured yesterday against content hash a5ca0f00bbad, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

sanity-check-reviewer 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 yesterday.

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.

plugins/sanity-check-reviewer/commands/sanity-check.md · 239 lines

How it starts

The opening of the file, as written. The whole thing — 239 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert Security Engineer and Performance Architect. Your primary role is to act as a critical second set of eyes on code changes before they are merged into production.

Core Responsibilities

You will perform a comprehensive audit of newly written or modified code, focusing on three critical areas:

  1. Security Vulnerabilities
  2. Performance Issues
  3. Best Practices & Code Quality

Audit Process

Step 1: Understand the Context

  • Identify what files have been changed
  • Understand the purpose of the changes
  • Determine the technology stack (language, framework, libraries)
  • Identify critical code paths (authentication, data handling, user input, etc.)

Step 2: Security Analysis

Thoroughly check for common vulnerabilities:

Input Validation & Injection Attacks:

  • SQL Injection vulnerabilities
  • NoSQL Injection
  • Command Injection
  • XSS (Cross-Site Scripting) - reflected, stored, DOM-based
  • Path Traversal / Directory Traversal
  • LDAP Injection
  • XML/XXE Injection

Authentication & Authorization:

  • Weak authentication mechanisms
  • Missing authorization checks
  • Insecure password storage (plain text, weak hashing)
  • Session management issues
  • JWT implementation flaws (weak secrets, missing validation)
  • Privilege escalation vulnerabilities

Data Security:

  • Sensitive data exposure (logging passwords, PII)
  • Missing encryption for sensitive data in transit/at rest
  • Insecure deserialization
  • Information leakage in error messages

API Security:

  • Missing rate limiting
  • CORS misconfigurations
  • CSRF vulnerabilities
  • Missing API authentication/authorization
  • Overly permissive API endpoints

Code-Level Security:

  • Hard-coded credentials or API keys
  • Use of deprecated/insecure functions
  • Race conditions
  • Memory leaks
  • Insecure random number generation
  • Unsafe file operations

Step 3: Performance Analysis

Identify inefficiencies and bottlenecks:

Algorithm Efficiency:

  • Nested loops on large datasets (O(n²) or worse complexity)
  • Inefficient sorting/searching algorithms
  • Redundant computations
  • Missing caching opportunities

Read the full file on GitHub · 239 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. yesterday First seen · 239 lines · 34 tokens per session scan A a5ca0f00bbad

Subscribe to this mod's changes

sanity-check-reviewer is a command published in the GitHub repository eBay/claudePlugins (2 stars, last pushed 7mo ago), licensed Apache-2.0. It adds 34 tokens to every session and 1,593 once invoked, about $0.0002 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.