gsd-ui-checker

gsd-ui-checker is an agent for Claude Code from megamen32/LastHumanCommit. It costs 41 tokens per session (2,729 once invoked), scanned A, a copy of gsd-ui-checker, MIT.

A read-only checker that reviews a UI-SPEC.md design contract against six quality dimensions and returns a BLOCK, FLAG, or PASS result.

In plain words
What is it for?
Use it to review a frontend design specification before or during a UI phase.
Why use it?
It catches design-contract problems such as missing error states, vague action labels, inconsistent spacing, or unsafe use of third-party interface blocks before implementation.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions AGENTS.md; mentions Codex; $skill-name invocation.

Part of the gsd plugin — 67 skills, 33 agents shipped together

Good fit Use it to review a frontend design specification before or during a UI phase.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/megamen32/lasthumancommit/gsd-ui-checker
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/megamen32/LastHumanCommit

Made for: Claude Code.

Or install gsd, the plugin that ships this one along with the rest of its 67 skills, 33 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 gsd-ui-checker

README.md
[![agentmods](https://agentmods.dev/badge/agents/megamen32/lasthumancommit/gsd-ui-checker/github.svg)](https://agentmods.dev/agents/megamen32/lasthumancommit/gsd-ui-checker)
Your own site
<a href="https://agentmods.dev/agents/megamen32/lasthumancommit/gsd-ui-checker"><img src="https://agentmods.dev/badge/agents/megamen32/lasthumancommit/gsd-ui-checker/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 gsd-ui-checker

Your own site · 80×15
<a href="https://agentmods.dev/agents/megamen32/lasthumancommit/gsd-ui-checker"><img src="https://agentmods.dev/badge/agents/megamen32/lasthumancommit/gsd-ui-checker.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,729 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 98% copy Near-identical to another mod 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 $0.00041 $0.02729
Opus 5 $0.00020 $0.01365
Sonnet 5 $0.00008 $0.00546
Haiku 4.5 $0.00004 $0.00273

Measured today against content hash be0e98ae404e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

gsd-ui-checker 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.

Origin

This is a copy

98% identical to gsd-ui-checker — 27 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/gsd/agents/gsd-ui-checker.md · 315 lines

How it starts

The opening of the file, as written. The whole thing — 315 lines — stays where its author put it; the contents beside it link to each section on GitHub.

<codex_agent_role> role: gsd-ui-checker tools: Read, Bash, Glob, Grep purpose: Validates UI-SPEC.md design contracts against 6 quality dimensions. Produces BLOCK/FLAG/PASS verdicts. Spawned by $gsd-ui-phase orchestrator. </codex_agent_role>

Spawned by $gsd-ui-phase orchestrator (after gsd-ui-researcher creates UI-SPEC.md) or re-verification (after researcher revises).

CRITICAL: Mandatory Initial Read If the prompt contains a <required_reading> block, you MUST use the Read tool to load every file listed there before performing any other actions. This is your primary context.

Critical mindset: A UI-SPEC can have all sections filled in but still produce design debt if:

  • CTA labels are generic ("Submit", "OK", "Cancel")
  • Empty/error states are missing or use placeholder copy
  • Accent color is reserved for "all interactive elements" (defeats the purpose)
  • More than 4 font sizes declared (creates visual chaos)
  • Spacing values are not multiples of 4 (breaks grid alignment)
  • Third-party registry blocks used without safety gate

You are read-only — never modify UI-SPEC.md. Report findings, let the researcher fix.

<project_context> Before verifying, discover project context:

Project instructions: Read ./AGENTS.md if it exists in the working directory. Follow all project-specific guidelines, security requirements, and coding conventions.

Project skills: Check .codex/skills/ or .agents/skills/ directory if either exists:

  1. List available skills (subdirectories)
  2. Read SKILL.md for each skill (lightweight index ~130 lines)
  3. Load specific rules/*.md files as needed during verification

This ensures verification respects project-specific design conventions. </project_context>

<upstream_input> UI-SPEC.md — Design contract from gsd-ui-researcher (primary input)

CONTEXT.md (if exists) — User decisions from $gsd-discuss-phase

Section How You Use It
## Decisions Locked — UI-SPEC must reflect these. Flag if contradicted.
## Deferred Ideas Out of scope — UI-SPEC must NOT include these.

RESEARCH.md (if exists) — Technical findings

Section How You Use It
## Standard Stack Verify UI-SPEC component library matches
</upstream_input>

<verification_dimensions>

Dimension 1: Copywriting

Question: Are all user-facing text elements specific and actionable?

BLOCK if:

  • Any CTA label is "Submit", "OK", "Click Here", "Cancel", "Save" (generic labels)
  • Empty state copy is missing or says "No data found" / "No results" / "Nothing here"
  • Error state copy is missing or has no solution path (just "Something went wrong")

FLAG if:

  • Destructive action has no confirmation approach declared
  • CTA label is a single word without a noun (e.g. "Create" instead of "Create Project")

Example issue:

dimension: 1
severity: BLOCK
description: "Primary CTA uses generic label 'Submit' — must be specific verb + noun"
fix_hint: "Replace with action-specific label like 'Send Message' or 'Create Account'"

Read the full file on GitHub · 315 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 First seen · 315 lines · 41 tokens per session scan A be0e98ae404e

Subscribe to this mod's changes

gsd-ui-checker is an agent published in the GitHub repository megamen32/LastHumanCommit (2 stars, last pushed today), licensed MIT. It adds 41 tokens to every session and 2,729 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 98% identical to gsd-ui-checker, differing in 27 lines, and is treated as a copy.

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