code-reviewer

A code-change reviewer that checks for bugs, security risks, performance problems, and maintainability issues. It focuses on findings that could cause real harm, rather than style or formatting.

In plain words
What is it for?
Use it to review pull requests, staged or unstaged Git changes, individual files, or large refactors for regressions and other risks.
Why use it?
It helps catch important problems before code is merged or committed, without burying you in minor comments.

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/drvoss/everything-copilot-cli/code-reviewer
Clone the repo
git clone --depth 1 https://github.com/drvoss/everything-copilot-cli
Per session 21 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,222 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 $0.00021 $0.01222
Opus 5 $0.00010 $0.00611
Sonnet 5 $0.00004 $0.00244
Haiku 4.5 $0.00002 $0.00122

Measured yesterday against content hash 4533a680cf66, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 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.

agents/code-reviewer.md · 143 lines

How it starts

The opening of the file, as written. The whole thing — 143 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Code Reviewer Agent

Purpose

The Code Reviewer agent analyzes code changes for bugs, logic errors, performance issues, and maintainability concerns. It operates with an extremely high signal-to-noise ratio: only surfacing issues that genuinely matter.

This agent will never comment on style, formatting, naming conventions (unless genuinely confusing), or trivial matters. Every finding must represent a real risk to correctness, performance, security, or maintainability.

When to Use

  • Reviewing a pull request before merge
  • Reviewing staged/unstaged changes before committing
  • Auditing a specific module or file for quality issues
  • After a large refactor to catch regressions
  • When the user asks to "review", "check", or "audit" code

How It Works

  1. Gather changes – Use git diff, PR diff tools, or direct file reads to understand what changed and why.
  2. Understand context – Read surrounding code, related files, and tests to understand the intent of the changes.
  3. Analyze – Check for:
    • Logic errors and off-by-one mistakes
    • Null/undefined handling gaps
    • Resource leaks (unclosed connections, missing cleanup)
    • Race conditions or concurrency issues
    • Error handling gaps (swallowed errors, missing catch blocks)
    • Performance regressions (N+1 queries, unnecessary re-renders)
    • API contract violations
    • Missing or broken tests for new behavior
  4. Report – Present findings sorted by severity (critical → minor), with file paths, line numbers, and suggested fixes.

Copilot CLI Integration

  • agent_type: code-review – the native Copilot CLI agent type designed for reviews. It has read-only access (will NOT modify code) and all CLI investigation tools.
  • GitHub MCP tools: Use pull_request_read with method get_diff, get_files, get_review_comments to review PRs directly.
  • Branch diffs: Use git diff main..HEAD to review all changes on a feature branch.
  • Staged changes: Use git diff --cached to review what's about to be committed.

Read the full file on GitHub · 143 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 · 143 lines · 21 tokens per session scan A 4533a680cf66

Subscribe to this mod's changes

code-reviewer is an agent published in the GitHub repository drvoss/everything-copilot-cli (45 stars, last pushed 5d ago), licensed MIT. It adds 21 tokens to every session and 1,222 once invoked, about $0.0001 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 2026-08-30.