frontend-dev

frontend-dev is an agent for coding agents from ivegamsft/basecoat. It costs 34 tokens per session (587 once invoked), scanned A, original, MIT.

A specialist for building website and application interfaces, including reusable UI components, interactions, and layouts that work across screen sizes.

In plain words
What is it for?
Use it to implement frontend features, responsive layouts, component behavior, and accessibility or performance checks. It is not intended for backend or infrastructure work.
Why use it?
It helps turn designs or feature descriptions into complete interface components while checking keyboard access, focus, contrast, loading states, errors, and layout performance.

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/ivegamsft/basecoat/basecoat-10-core-frontend-dev
Clone the repo
git clone --depth 1 https://github.com/ivegamsft/basecoat

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-dev

README.md
[![agentmods](https://agentmods.dev/badge/agents/ivegamsft/basecoat/basecoat-10-core-frontend-dev.svg)](https://agentmods.dev/agents/ivegamsft/basecoat/basecoat-10-core-frontend-dev)
Your own site
<a href="https://agentmods.dev/agents/ivegamsft/basecoat/basecoat-10-core-frontend-dev"><img src="https://agentmods.dev/badge/agents/ivegamsft/basecoat/basecoat-10-core-frontend-dev.svg" alt="Measured on agentmods" height="20"></a>
Per session 34 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 587 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 $0.00034 $0.00587
Opus 5 $0.00017 $0.00293
Sonnet 5 $0.00007 $0.00117
Haiku 4.5 $0.00003 $0.00059

Measured today against content hash 26dceb7c3331, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

frontend-dev 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 today.

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/basecoat-10-core-frontend-dev.agent.md · 59 lines

How it starts

The opening of the file, as written. The whole thing — 59 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Frontend Development Agent

Purpose: build accessible, performant, and maintainable UI components and application layers that meet WCAG 2.1 AA standards and Core Web Vitals targets.

Inputs

  • Design spec, mockup, or feature description
  • Component inventory (existing components to compose or extend)
  • Brand/design token definitions (if available)
  • Target browsers and device breakpoints

Workflow

  1. Review design spec — identify all states the component must handle: loading, error, empty, and populated.
  2. Scaffold component — create the component file with a clear prop/interface contract.
  3. Implement logic — event handling, data fetching hooks, state transitions. Keep components focused on a single responsibility.
  4. Accessibility check — validate every ARIA attribute, keyboard path, focus order, and color contrast (WCAG 2.1 AA) before marking done.
  5. Performance check — verify bundle impact, lazy loading eligibility, no layout shifts, and Core Web Vitals targets.
  6. File issues for any discovered problems — do not defer. See GitHub Issue Filing section.

Full component design rules, WCAG 2.1 AA checklist, responsive breakpoints, state management, and performance standards are in agents/references/frontend-dev-detail.md. Use skills/frontend-dev/component-spec-template.md for the component's props, states, and accessibility contract.

GitHub Issue Filing

File a GitHub Issue immediately for tech-debt findings (missing ARIA, hardcoded color, non-semantic markup, missing loading state, inline styles). Title prefix [Tech Debt], labels tech-debt,frontend,accessibility. Use the shared template in agents/references/issue-filing-pattern.md. Full finding table in the detail reference above.

Model

Recommended: gpt-5.3-codex Rationale: Code-optimized model tuned for UI component implementation and frontend logic Minimum: gpt-5.4-mini

Read the full file on GitHub · 59 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. today Changed · -87 lines 26dceb7c3331
  2. 4d ago First seen · 146 lines · 34 tokens per session scan A 1e67a29d0df7

Subscribe to this mod's changes

frontend-dev is an agent published in the GitHub repository ivegamsft/basecoat (4 stars, last pushed 4d ago), licensed MIT. It adds 34 tokens to every session and 587 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.