SWE - Performance Reviewer

SWE - Performance Reviewer is an agent for Claude Code from chrisallenlane/claude-swe-workflows. It costs 25 tokens per session (1,956 once invoked), scanned A, original, MIT.

A software agent that reviews code for computational performance issues, such as slow algorithms or missing benchmarks. It gives advice but does not make the changes itself.

In plain words
What is it for?
Use it to review new algorithms, data-processing code, performance-sensitive changes, benchmarks, and profiling coverage.
Why use it?
It helps find likely slow paths and gaps in performance testing before they affect users or become harder to measure.

Agent for Claude Code

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

Part of the claude-swe-workflows plugin — 17 skills, 40 agents shipped together

Good fit Use it to review new algorithms, data-processing code, performance-sensitive changes, benchmarks, and profiling coverage.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/chrisallenlane/claude-swe-workflows/swe-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/chrisallenlane/claude-swe-workflows

Made for: Claude Code.

Or install claude-swe-workflows, the plugin that ships this one along with the rest of its 17 skills, 40 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 SWE - Performance Reviewer

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

Your own site · 80×15
<a href="https://agentmods.dev/agents/chrisallenlane/claude-swe-workflows/swe-perf-reviewer"><img src="https://agentmods.dev/badge/agents/chrisallenlane/claude-swe-workflows/swe-perf-reviewer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 25 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,956 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 $0.00025 $0.01956
Opus 5 $0.00013 $0.00978
Sonnet 5 $0.00005 $0.00391
Haiku 4.5 $0.00003 $0.00196

Measured 11d ago against content hash a397f59e9622, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

SWE - Performance 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 11d 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/swe-perf-reviewer.md · 217 lines

How it starts

The opening of the file, as written. The whole thing — 217 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Purpose

Review the codebase for computational performance issues — algorithmic bottlenecks, missing benchmarks, profiling gaps, and optimization opportunities. This is an advisory role — you identify performance problems and recommend fixes, but you don't implement changes yourself. Another agent implements your recommendations.

Workflow

  1. Scan: Analyze codebase for performance-critical code, existing benchmarks, and profiling infrastructure
  2. Assess: Determine if performance work is needed based on code changes and findings
  3. Report: If performance-critical issues detected, report findings with recommendations; if no performance impact, report and exit

When to Skip Work

Exit immediately if:

  • Changes are not performance-critical (UI text, docs, comments, simple CRUD)
  • No hot paths were modified
  • Adequate benchmarks already exist for changed code
  • Changes are refactoring-only with no algorithmic changes

Report "No performance work needed" and exit.

When to Do Work

Report findings for:

  • New algorithms or data structures missing benchmarks
  • Modified hot paths (loops, recursive functions, data processing)
  • Public API functions that process data without benchmarks
  • Database query changes without performance validation
  • Clear algorithmic improvements (O(n^2) to O(n log n))
  • Obvious inefficiencies (repeated work in loops, unnecessary allocations)
  • Missing profiling infrastructure

Performance Testing Strategy

Benchmark Testing

  • Micro-benchmarks: Measure individual functions/operations (sorting, hashing, parsing)
  • Macro-benchmarks: Measure realistic workloads (API request end-to-end, batch processing)
  • Regression detection: Track performance over time, alert on degradation

Profiling

  • CPU profiling: Identify hot functions consuming CPU time
  • Memory profiling: Track allocations, identify leaks and excessive memory use
  • Allocation profiling: Count allocations in hot paths (allocation-free is often critical)
  • Flamegraphs: Visualize where time is spent in call stacks

Read the full file on GitHub · 217 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. 11d ago First seen · 217 lines · 25 tokens per session scan A a397f59e9622

Subscribe to this mod's changes

SWE - Performance Reviewer is an agent published in the GitHub repository chrisallenlane/claude-swe-workflows (18 stars, last pushed 3mo ago), licensed MIT. It adds 25 tokens to every session and 1,956 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.

Related

Other agents, from other repositories

afc-architect

Architecture analysis agent — invoked during plan phase for ADR recording and review phase for architecture compliance checks. Remembers ADR decisions and architecture patterns across sessions to provide consistent design guidance.

jhlee0409/all-for-claudecode · 39 tokens

afc-pr-analyst

PR deep analysis worker — invoked during /afc:triage for deep PR verification. Performs build/test/lint verification in an isolated worktree for triage.

jhlee0409/all-for-claudecode · 40 tokens

afc-security

Security scanning agent — invoked during review phase for security vulnerability scanning. Remembers vulnerability patterns and project-specific security characteristics across sessions to improve scan precision.

jhlee0409/all-for-claudecode · 33 tokens

code-reviewer

A code-review agent that checks whether changes follow their specification and assesses code quality, security, maintainability, and performance. It reports findings with severity levels and file-and-line references.

sangrokjung/claude-forge · 96 tokens

adversarial-reviewer

Independent read-only checker for behavioural changes. Runs in a fresh context that did not author the change, reproduces the claim against the goal, spec, diff and execution evidence, and returns exactly one verdict — APPROVE, REQUESTCHANGES or UNVERIFIED — as a forge.review/v1 envelope. MUST BE USED before claiming…

sangrokjung/claude-forge · 102 tokens

refactor-cleaner

An agent for finding and safely removing dead code, unused exports, unused dependencies, and duplicate implementations.

sangrokjung/claude-forge · 109 tokens