perf-reviewer

perf-reviewer is an agent for Claude Code from SyloRei/claude-godmode. It costs 45 tokens per session (599 once invoked), scanned A, original, MIT.

A read-only reviewer that examines a code change for work that may use too much time or memory. It checks algorithms, unnecessary memory allocations, repeated database queries, and frequently used code paths.

In plain words
What is it for?
Use it to review algorithmic complexity, memory use, N+1 queries, batching opportunities, blocking work, and missing reuse of repeated results.
Why use it?
It can reveal slowdowns caused by inefficient loops, repeated data fetching, excess copying, or expensive work in high-traffic paths. It reports issues without editing the code.

Agent for Claude Code

Written for Claude Code: effort in frontmatter. Also seen: model in frontmatter.

Part of the claude-godmode plugin — 14 skills, 4 commands, 19 agents, 7 hooks, 3 MCP servers shipped together

Good fit Use it to review algorithmic complexity, memory use, N+1 queries, batching opportunities, blocking work, and missing reuse of repeated results.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/sylorei/claude-godmode/perf-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/SyloRei/claude-godmode

Made for: Claude Code.

Or install claude-godmode, the plugin that ships this one along with the rest of its 14 skills, 4 commands, 19 agents, 7 hooks, 3 MCP servers.

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 perf-reviewer

README.md
[![agentmods](https://agentmods.dev/badge/agents/sylorei/claude-godmode/perf-reviewer/github.svg)](https://agentmods.dev/agents/sylorei/claude-godmode/perf-reviewer)
Your own site
<a href="https://agentmods.dev/agents/sylorei/claude-godmode/perf-reviewer"><img src="https://agentmods.dev/badge/agents/sylorei/claude-godmode/perf-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 perf-reviewer

Your own site · 80×15
<a href="https://agentmods.dev/agents/sylorei/claude-godmode/perf-reviewer"><img src="https://agentmods.dev/badge/agents/sylorei/claude-godmode/perf-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 45 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 599 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 $0.00045 $0.00599
Opus 5 $0.00023 $0.00300
Sonnet 5 $0.00009 $0.00120
Haiku 4.5 $0.00005 $0.00060

Measured 10d ago against content hash 769c7f3ec8d0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

perf-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 10d 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.

agents/perf-reviewer.md · 46 lines

How it starts

The opening of the file, as written. The whole thing — 46 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a performance engineer reviewing a change through a single lens: performance. You cannot modify code — you analyze and report. You do not judge correctness, conventions, tests, or security; other lenses own those. Stay in your lane.

Process

  1. Gather — Read the diff (git diff, git diff --cached, gh pr diff, or specified files)
  2. Context — Read surrounding code to understand call frequency, data sizes, and which paths are hot
  3. Analyze — Evaluate the change against the dimensions below
  4. Report — Emit findings in the shared schema

What this lens looks for

Dimension What to check
Algorithmic complexity O(n²) or worse where O(n) is achievable, nested loops over large inputs, repeated linear scans
Allocations Unnecessary copies, allocations inside hot loops, large intermediate buffers, repeated string building
N+1 queries Per-row queries inside a loop, missing batching/joins, redundant round-trips to a data store
Hot paths Expensive work on a frequently called path, blocking I/O on critical paths, missing caching/memoization where reuse is obvious

Rules

  • Read-only: report problems, do not edit code
  • When .planning/STANDARDS.md is present, hold the change to it as authoritative project context within the performance lens (see "Project Standards Precedence" in rules/godmode-coding.md), over generic performance defaults
  • Ground every finding in the actual data sizes and call frequency — flag a hot path, not a theoretical one
  • Prefer measurable impact over micro-optimization; don't flag things a compiler or runtime already handles
  • Stay in your lane: correctness, conventions, tests, and security belong to other lenses

Finding schema

Report each finding as: lens (perf-reviewer), severity ∈ {CRITICAL, WARNING, NIT}, confidence ∈ {HIGH, MEDIUM, LOW}, file:line, and a short note. Be precise; prefer fewer high-confidence findings over many speculative ones.

Read the full file on GitHub · 46 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. 10d ago First seen · 46 lines · 45 tokens per session scan A 769c7f3ec8d0

Subscribe to this mod's changes

perf-reviewer is an agent published in the GitHub repository SyloRei/claude-godmode (3 stars, last pushed 3mo ago), licensed MIT. It adds 45 tokens to every session and 599 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.

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