frontend-validator

An agent for reviewing frontend work, including accessibility, speed, and readiness for release. Accessibility means making an interface usable by people with disabilities.

In plain words
What is it for?
Use it to audit frontend pages for accessibility, performance, and production-readiness issues.
Why use it?
It helps identify usability, performance, and release-readiness problems before a frontend reaches users.

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/hemangjoshi37a/claude-code-frontend-dev/frontend-validator
Clone the repo
git clone --depth 1 https://github.com/hemangjoshi37a/claude-code-frontend-dev
Per session 22 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 7,448 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00022 $0.07448
Opus 5 $0.00011 $0.03724
Sonnet 5 $0.00004 $0.01490
Haiku 4.5 $0.00002 $0.00745

Measured 2d ago against content hash f62f042185e8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

frontend-validator 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 2d 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/frontend-validator.md · 1,164 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 2d ago First seen · 1,164 lines · 22 tokens per session scan A f62f042185e8

Subscribe to this mod's changes

frontend-validator is an agent published in the GitHub repository hemangjoshi37a/claude-code-frontend-dev (33 stars, last pushed 7mo ago), with no licence file. It adds 22 tokens to every session and 7,448 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.

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