frontend-optimizer

frontend-optimizer is an agent for Claude Code from drvoss/harness-100-copilot. It costs 52 tokens per session (1,431 once invoked), scanned A, original, no licence file.

A frontend-performance agent for improving website loading, interaction speed, and layout stability.

In plain words
What is it for?
Use it to improve Core Web Vitals, reduce bundle size, add lazy loading, optimize images, and configure CDN caching.
Why use it?
It helps reduce the delays caused by large JavaScript bundles, unoptimized images, unnecessary loading, and inefficient caching.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md).

Good fit Use it to improve Core Web Vitals, reduce bundle size, add lazy loading, optimize images, and configure CDN caching.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/drvoss/harness-100-copilot/frontend-optimizer
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/drvoss/harness-100-copilot

Made for: Claude Code.

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 frontend-optimizer

README.md
[![agentmods](https://agentmods.dev/badge/agents/drvoss/harness-100-copilot/frontend-optimizer/github.svg)](https://agentmods.dev/agents/drvoss/harness-100-copilot/frontend-optimizer)
Your own site
<a href="https://agentmods.dev/agents/drvoss/harness-100-copilot/frontend-optimizer"><img src="https://agentmods.dev/badge/agents/drvoss/harness-100-copilot/frontend-optimizer/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 frontend-optimizer

Your own site · 80×15
<a href="https://agentmods.dev/agents/drvoss/harness-100-copilot/frontend-optimizer"><img src="https://agentmods.dev/badge/agents/drvoss/harness-100-copilot/frontend-optimizer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 52 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,431 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 unknown 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 $0.00052 $0.01431
Opus 5 $0.00026 $0.00715
Sonnet 5 $0.00010 $0.00286
Haiku 4.5 $0.00005 $0.00143

Measured 6d ago against content hash 01ca946d7b1e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

frontend-optimizer 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 6d 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.

harnesses/29-performance-optimizer/agents/frontend-optimizer.md · 158 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 6d ago First seen · 158 lines · 52 tokens per session scan A 01ca946d7b1e

Subscribe to this mod's changes

frontend-optimizer is an agent published in the GitHub repository drvoss/harness-100-copilot (5 stars, last pushed 3mo ago), with no licence file. It adds 52 tokens to every session and 1,431 once invoked, about $0.0003 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 2026-09-03.

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