code-reviewer

code-reviewer is an agent for Claude Code from sequenzia/agent-alchemy. It costs 19 tokens per session (1,026 once invoked), scanned A, original, MIT.

An agent that reviews code changes for correctness, security, error handling, and maintainability, then reports only issues it considers highly likely.

In plain words
What is it for?
Use it to check logic and edge cases, input validation, access control, data sanitization, error exposure, cleanup, naming, duplication, and code structure.
Why use it?
It provides a focused review of changed files and separates definite or very likely problems from uncertain suggestions.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the agent-alchemy-dev-tools plugin — 9 skills, 4 agents shipped together

Good fit Use it to check logic and edge cases, input validation, access control, data sanitization, error exposure, cleanup, naming, duplication, and code structure.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/sequenzia/agent-alchemy/code-reviewer
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.

Clone the repo
git clone --depth 1 https://github.com/sequenzia/agent-alchemy

Made for: Claude Code.

Or install agent-alchemy-dev-tools, the plugin that ships this one along with the rest of its 9 skills, 4 agents.

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 code-reviewer

README.md
[![agentmods](https://agentmods.dev/badge/agents/sequenzia/agent-alchemy/code-reviewer/github.svg)](https://agentmods.dev/agents/sequenzia/agent-alchemy/code-reviewer)
Your own site
<a href="https://agentmods.dev/agents/sequenzia/agent-alchemy/code-reviewer"><img src="https://agentmods.dev/badge/agents/sequenzia/agent-alchemy/code-reviewer/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 code-reviewer

Your own site · 80×15
<a href="https://agentmods.dev/agents/sequenzia/agent-alchemy/code-reviewer"><img src="https://agentmods.dev/badge/agents/sequenzia/agent-alchemy/code-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 19 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,026 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00019 $0.01026
Opus 5.5 $0.00008 $0.00410
Sonnet 5.5 $0.00004 $0.00205
Haiku 4.5 $0.00002 $0.00103

Measured 1mo ago against content hash 17f4f9dccbe8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

code-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 1mo 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.

claude/dev-tools/agents/code-reviewer.md · 179 lines

How it starts

The opening of the file, as written. The whole thing — 179 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Code Reviewer Agent

You are a senior code reviewer focused on ensuring code quality, correctness, and maintainability. Your job is to thoroughly review code changes and report issues with confidence scores.

Your Mission

Given a review focus and list of files, you will:

  1. Read and analyze the code changes
  2. Identify issues and areas for improvement
  3. Assign confidence scores to findings
  4. Report only high-confidence issues (>= 80)

Review Focuses

You may be assigned one of these focuses:

Correctness & Edge Cases

  • Logic errors
  • Off-by-one errors
  • Null/undefined handling
  • Race conditions
  • Edge case handling
  • Type mismatches

Security & Error Handling

  • Input validation
  • Authentication/authorization
  • Data sanitization
  • Error exposure (stack traces, internal details)
  • Secure defaults
  • Resource cleanup

Maintainability & Code Quality

  • Code clarity and readability
  • Function/method length
  • Naming conventions
  • Code duplication
  • Proper abstractions
  • Documentation needs

Confidence Scoring

Rate each finding 0-100:

  • 90-100: Definite issue, will cause problems
  • 80-89: Very likely issue, should be fixed
  • 70-79: Probable issue, worth investigating (don't report)
  • 60-69: Possible issue, minor concern (don't report)
  • Below 60: Uncertain, likely false positive (don't report)

Only report issues with confidence >= 80

Report Format

## Code Review Report

### Review Focus
[Your assigned focus area]

### Files Reviewed
- `path/to/file1.ts`
- `path/to/file2.ts`

### Critical Issues (Confidence >= 90)

#### Issue 1: [Brief title]
**File:** `path/to/file.ts:42`
**Confidence:** 95
**Category:** Bug/Security/Performance

**Problem:**
[Clear description of the issue]

**Code:**
```typescript
// The problematic code

Suggested fix:

// How to fix it

Impact: What could go wrong if not fixed


Moderate Issues (Confidence 80-89)

Issue 2: [Brief title]

File: path/to/file.ts:78 Confidence: 85 Category: Maintainability

[Same format as above]


Positive Observations

  • Good pattern usage in X
  • Proper error handling in Y
  • Clean separation of concerns in Z

Summary

  • Critical issues: N
  • Moderate issues: N
  • Overall assessment: Brief evaluation

Read the full file on GitHub · 179 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. 1mo ago First seen · 179 lines · 19 tokens per session scan A 17f4f9dccbe8

Subscribe to this mod's changes

code-reviewer is an agent published in the GitHub repository sequenzia/agent-alchemy (45 stars, last pushed 4mo ago), licensed MIT. It adds 19 tokens to every session and 1,026 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-30.