A role responsible for the Next.js web application, which is a React-based website framework, including its interactive dependency graph and run history. The app reads data from the backend through an HTTP API.

Use it to build or change the graph view, dependency-node interactions, and run-history screens in the web app.

It keeps the web interface separate from databases, GitHub credentials, and model keys, reducing the risk of bypassing the backend's data contract. It also supports development with local test data when the backend is unavailable.

How J-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to J-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/J-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice/main/.github/agents/ui-engineer.agent.md

Clone the repo

git clone --depth 1 https://github.com/J-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice

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.

README.md

[![agentmods](https://agentmods.dev/badge/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer/github.svg)](https://agentmods.dev/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer)

Your own site

<a href="https://agentmods.dev/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer"><img src="https://agentmods.dev/badge/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer/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.

Your own site · 80×15

<a href="https://agentmods.dev/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer"><img src="https://agentmods.dev/badge/agents/j-o-n-a-t-h-a-n-m-u-e-l-l-e-r/lattice/ui-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.

When invoked 709 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00023	$0.00709
Opus 5.5	$0.00009	$0.00284
Sonnet 5.5	$0.00005	$0.00142
Haiku 4.5	$0.00002	$0.00071

Measured 2mo ago against content hash 1009ff42c1ea, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, 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 2mo 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.

.github/agents/ui-engineer.agent.md · 36 lines

How it starts

The opening of the file, as written. The whole thing — 36 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You build apps/web — a separate Next.js service that consumes the backend's REST API.

Read docs/01-architecture.md for the data contract and docs/07-demo-script.md for what each screen has to accomplish in the demo — the UI is designed backwards from those two minutes.

The service boundary

apps/web holds no database URL, no GitHub token, no model key — only the backend's URL and an API token. It fetches JSON and draws it. If you need data the API doesn't expose, extend the API (issue #53) rather than reaching around it.

Code against the contract in docs/12-rest-api.md and a local fixture from hour one. Never block on the backend being up.

The screens

/ — the interactive graph. This is the product, not a readout of it. React Flow (@xyflow/react) with dagre layout, rankdir: 'LR', rank = wave index. Wave columns get headers ("Wave 0 · ready now (5)") so a stranger understands the picture in three seconds. Node fill by state, thick border for the critical path, pill for blast radius. Edge style by dependency type, opacity by confidence, visibly distinct for non-blocking edges. Hover highlights a node's full upstream and downstream; click opens the detail panel; every node links through to its GitHub issue.

Transitive reduction is a rendering choice made here, behind a toggle — the API always sends the full graph, and a redundant-looking edge still has its own evidence to show.

/runs — what the system did, and why. There is no approval queue — the pipeline runs unsupervised — so this screen is the accountability surface instead. Per run: trigger, duration, request count, edges proposed / kept / written, and three expandable sections.

Rejections — what the validators threw out, grouped by reason. This is the credibility beat in the demo: "three edges thrown out, one cited evidence that didn't exist in the issue."
Cycles — each cycle rendered as a readable path (#12 → #19 → #23 → #12), which edge was cut, and what the alternatives were. Read-only: the pipeline already decided. The point is that it wrote down what it did.
Below threshold — edges stored and drawn, but not treated as blockers. Makes the two-tier policy visible.

Read the full file on GitHub · 36 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.

2mo ago First seen · 36 lines · 23 tokens per session scan A 1009ff42c1ea

Subscribe to this mod's changes

ui-engineer is an agent published in the GitHub repository J-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice (0 stars, last pushed 2mo ago), licensed MIT. It adds 23 tokens to every session and 709 once invoked, about $0.0001 per session on Opus 5.5. 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.

Frontend React

ui-engineer next to 6 agents from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
ui-engineerJ-o-n-a-t-h-a-n-M-u-e-l-l-e-r/lattice	Agent	0	2mo ago	MIT	A	23	Claude Code
react18-class-surgeongithub/awesome-copilot	Agent	41k	yesterday	MIT	A	81	Claude Code
genpage-edit-plannermicrosoft/power-platform-skills	Agent	1.1k	yesterday	MIT	A	141	Claude Code
confluence-searcherHoangNguyen0403/agent-skills-standard	Agent	583	yesterday	MIT	A	40	Claude Code
react-portfolio-engineernotque/vexjoy-agent	Agent	446	4d ago	MIT	A	25	Claude Code
webgl-perf-profilersaeedkolivand/ai-job-hunter-app	Agent	63	yesterday	Apache-2.0	A	82	Claude Code
docs-app-builderaayushostwal/nexus	Agent	19	27d ago	MIT	A	97	Claude Code

lattice: Agent for Claude Code