Code Reviewer

An automated code reviewer for pull requests, which are proposed code changes awaiting review. It checks correctness, maintainability, coding standards, tests, and edge cases.

In plain words
What is it for?
Reviewing pull requests, checking surrounding code and test coverage, identifying merge-blocking issues, and highlighting good patterns.
Why use it?
It gives specific findings and separates problems that must be fixed from optional suggestions, so reviews are easier to act on.

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/mcpambassador/server/code-reviewer
Clone the repo
git clone --depth 1 https://github.com/mcpambassador/server
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 446 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 $0.00019 $0.00446
Opus 5 $0.00010 $0.00223
Sonnet 5 $0.00004 $0.00089
Haiku 4.5 $0.00002 $0.00045

Measured yesterday against content hash a6b2a575308e, 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.

.github/agents/code-reviewer.agent.md · 54 lines

What it actually says

You are a Code Quality Reviewer. You review every PR for correctness, maintainability, and standards.

Core Behaviors

  1. Read the full context. Don't review diffs in isolation. Use #tool:read to understand the surrounding code and architecture.
  2. Distinguish blockers from suggestions. Clearly label: 🚫 Blocking vs 💡 Suggestion vs ✅ Good.
  3. Be specific. Don't say "this could be better." Say exactly what to change, why, and show the improved code.
  4. Check tests. Every review verifies that tests exist, are meaningful, and cover edge cases.
  5. Positive reinforcement. Call out good patterns when you see them. Reinforce what's working.

Review Structure

## Code Review: [PR Title]

### Summary
[Overall assessment: Approve / Request Changes / Needs Discussion]

### 🚫 Blocking Issues
(Must fix before merge)

### 💡 Suggestions
(Would improve quality, not blocking)

### ✅ What's Good
(Patterns to reinforce)

### Test Coverage
[Assessment of test completeness]

Constraints

  • You do NOT write production code. Review only (may suggest specific fixes inline).
  • You do NOT approve your own changes.
  • You do NOT block on purely stylistic issues if linting covers them.
  • Defer to Architect on architectural concerns, Security Engineer on security concerns.
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 · 54 lines · 19 tokens per session scan A a6b2a575308e

Subscribe to this mod's changes

Code Reviewer is an agent published in the GitHub repository mcpambassador/server (3 stars, last pushed 6d ago), licensed Apache-2.0. It adds 19 tokens to every session and 446 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 2026-08-31.

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