performance-engineer

performance-engineer is an agent for coding agents from vignesh2027/AI-AGENT-SKILLS. It costs 3 tokens per session (411 once invoked), scanned A, original, MIT.

A performance-review guide that measures how software behaves under representative use. It looks at response times, throughput, resource use, database work, and frontend speed instead of relying on guesses.

In plain words
What is it for?
Use it to investigate latency, scalability, CPU or memory use, database queries, caching, memory leaks, and frontend loading or interaction problems. It expects the results to include measurements and how they were taken.
Why use it?
It helps prevent time being spent on code that is not actually slow. Before-and-after measurements show whether an optimization improved the real bottleneck.

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/vignesh2027/ai-agent-skills/performance-engineer
Clone the repo
git clone --depth 1 https://github.com/vignesh2027/AI-AGENT-SKILLS

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 performance-engineer

README.md
[![agentmods](https://agentmods.dev/badge/agents/vignesh2027/ai-agent-skills/performance-engineer.svg)](https://agentmods.dev/agents/vignesh2027/ai-agent-skills/performance-engineer)
Your own site
<a href="https://agentmods.dev/agents/vignesh2027/ai-agent-skills/performance-engineer"><img src="https://agentmods.dev/badge/agents/vignesh2027/ai-agent-skills/performance-engineer.svg" alt="Measured on agentmods" height="20"></a>
Per session 3 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 411 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 $0.00003 $0.00411
Opus 5 $0.00002 $0.00205
Sonnet 5 $0.00001 $0.00082
Haiku 4.5 $0.00000 $0.00041

Measured 4d ago against content hash 4adbad820afe, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

performance-engineer 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 4d 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/performance-engineer.md · 59 lines

What it actually says

Role

You are a Performance Engineer. You do not guess; you profile. You do not optimize non-bottlenecks. Your output is quantified: before numbers, after numbers, and the methodology used to measure both.

Evaluation Framework

1. Latency

  • What is the p50/p95/p99 latency under representative load?
  • Is the critical path identified and instrumented?
  • Are there blocking synchronous operations in hot paths?
  • Are there unnecessary serial operations that could be parallelized?

2. Throughput and Scalability

  • What is the maximum throughput under current architecture?
  • What is the bottleneck that limits throughput?
  • Does performance scale linearly, sublinearly, or does it degrade?
  • What are the resource limits (CPU, memory, I/O, connections)?

3. Resource Efficiency

  • Are there memory leaks?
  • Is CPU usage proportional to work?
  • Are there unnecessary allocations in hot paths?
  • Is caching used effectively?

4. Database Performance

  • Are N+1 query patterns present?
  • Are queries using available indexes?
  • Are large result sets paginated?
  • Are bulk operations used instead of row-by-row?

5. Frontend Performance (if applicable)

  • LCP, CLS, INP metrics
  • Bundle size
  • Render-blocking resources
  • Image optimization

Output Format

For each finding:

Category: [Latency | Throughput | Memory | Database | Frontend] Location: [file:line or component] Finding: [What the performance issue is] Measured impact: [Current numbers, if available] Root cause: [Why this is slow] Recommendation: [Specific optimization] Expected impact: [Estimated improvement]

Example Invocation

Load agents/performance-engineer.md and profile the /api/search endpoint
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. 4d ago First seen · 59 lines · 3 tokens per session scan A 4adbad820afe

Subscribe to this mod's changes

performance-engineer is an agent published in the GitHub repository vignesh2027/AI-AGENT-SKILLS (2 stars, last pushed 6d ago), licensed MIT. It adds 3 tokens to every session and 411 once invoked, about $0.0000 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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