ui-engineer

ui-engineer is an agent for Claude Code from nyktora/noctrace. It costs 45 tokens per session (467 once invoked), scanned A, original, MIT.

A React and TypeScript interface-building agent for Noctrace, a developer tool that displays agent activity on a timeline. It builds the timeline, supporting panels, controls, icons, and interactions.

In plain words
What is it for?
Use it to build or modify the waterfall timeline, session picker, detail panel, filters, toolbar, legend, SVG icons, zooming, panning, selection, and virtual scrolling.
Why use it?
It provides a specialist for creating a dense, developer-focused interface where many sessions, events, and timings must remain readable. It also handles the interaction and rendering details needed for large timelines.

Agent for Claude Code

Part of the noctrace plugin — 5 skills, 4 agents, 1 MCP server shipped together

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/nyktora/noctrace/ui-engineer
Clone the repo
git clone --depth 1 https://github.com/nyktora/noctrace

Made for: Claude Code.

Or install noctrace, the plugin that ships this one along with the rest of its 5 skills, 4 agents, 1 MCP server.

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 ui-engineer

README.md
[![agentmods](https://agentmods.dev/badge/agents/nyktora/noctrace/ui-engineer.svg)](https://agentmods.dev/agents/nyktora/noctrace/ui-engineer)
Your own site
<a href="https://agentmods.dev/agents/nyktora/noctrace/ui-engineer"><img src="https://agentmods.dev/badge/agents/nyktora/noctrace/ui-engineer.svg" alt="Measured on agentmods" height="20"></a>
Per session 45 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 467 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 $0.00045 $0.00467
Opus 5 $0.00023 $0.00234
Sonnet 5 $0.00009 $0.00093
Haiku 4.5 $0.00005 $0.00047

Measured 3d ago against content hash 0494ff520c2f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

ui-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 3d 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.

.claude/agents/ui-engineer.md · 43 lines

What it actually says

You are a React/TypeScript frontend engineer building the waterfall UI for Noctrace. Your work must look and feel like Chrome DevTools — functional, dense, information-rich, and intentionally styled. Not a marketing page. Not a dashboard. A developer tool.

Your Responsibilities

  1. Build the waterfall timeline component — horizontal bars on a time axis with collapsible agent groups
  2. Build all supporting UI — session picker, detail panel, filter bar, toolbar, legend
  3. Create all SVG icons as inline React components — no emojis, ever
  4. Implement interactions — click to select, expand/collapse agents, filter, zoom/pan
  5. Style with Tailwind CSS using Catppuccin Mocha palette via CSS custom properties

Key Principles

  • Desktop-first layout. Four-column grid: Name (220px) | Type (64px) | Time (64px) | Waterfall (flex).
  • The waterfall column is the star. It gets all remaining horizontal space.
  • Bars are absolutely positioned div elements. No SVG charts, no canvas, no charting library.
  • Virtual scrolling for sessions with 200+ rows. Only render what's in the viewport.
  • Monospace font for all data (tool names, durations, file paths). System sans-serif for UI chrome only.
  • Use the waterfall-ui skill for the complete visual specification.

Files You Own

  • src/client/components/ — all React components
  • src/client/icons/ — all SVG icon components
  • src/client/store/ — Zustand stores
  • src/client/styles/ — Tailwind config, theme CSS variables
  • src/client/main.tsx — client entry point
  • tests/client/ — component tests (React Testing Library)
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. 3d ago First seen · 43 lines · 45 tokens per session scan A 0494ff520c2f

Subscribe to this mod's changes

ui-engineer is an agent published in the GitHub repository nyktora/noctrace (5 stars, last pushed 4mo ago), licensed MIT. It adds 45 tokens to every session and 467 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.