ui

A guide for choosing how to show information in a local web chat: as Markdown, an HTML message, or a persistent interface panel. It explains the trade-offs and rendering rules for each option.

In plain words
What is it for?
Use it when sending tables, dashboards, diagrams, status views, or other structured content to a web-chat channel.
Why use it?
It helps prevent structured information from becoming hard to read in a plain chat reply.

Skill for Claude CodeCodex

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 skills/tkellogg/open-strix/ui
Any agent
npx skills add tkellogg/open-strix --skill ui
Clone the repo
git clone --depth 1 https://github.com/tkellogg/open-strix

Made for: Claude Code, Codex.

Per session 96 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,907 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 $0.00096 $0.01907
Opus 5 $0.00048 $0.00954
Sonnet 5 $0.00019 $0.00381
Haiku 4.5 $0.00010 $0.00191

Measured 2d ago against content hash 311b40ac5465, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

ui 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.

open_strix/builtin_skills/ui/SKILL.md · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Choosing the right surface

There are three surfaces in the local web UI. Pick by asking what shape the content has, not how long it is.

Surface When What it gives you What it costs
Markdown message Quick reply, single point, conversational. Cheap, scrollable with the chat. Linear — every reply pushes older ones up.
HTML message One-off rich artifact: a table, a status card, a small dashboard, a diagram, a labelled diff. The shape is non-linear but the lifetime is "until the next message scrolls it away." Tables, grids, layered SVG, color/typography, and small scripts under your control. Renders inline in chat. Can use parent-owned data-strix-action hooks or window.strix. Ephemeral; sandboxed with no same-origin access. Cream background — see below.
UI plugin A frame of mind that is not linear like chat. Persistent. Tim wants to see what we're talking about, not just discuss it. Example: chainlink issues — the chat thread talks about them, the plugin shows them, with detail views, filters, status. A live, interactive, scrollable side panel that survives across turns. Full JS, can poll, can show fresh state. Costs a server. Has a contract: see ui-plugins.md.

Mental model (from Tim, 2026-05-12):

"I want UI plugins to share a frame of mind that's not linear like chat. With chainlink, I couldn't see any of the chainlink issues — now I can."

If you find yourself describing state in prose ("here are the 7 open RLS findings, here are their statuses, here's which ones map to PR #X..."), you're papering over a missing UI plugin. Either fire off an HTML message now and propose the plugin, or just build the plugin.


Rule of thumb (when in doubt)

  1. Quick reply, no shape? → markdown.
  2. One artifact you wouldn't want to scroll back to find? → HTML message. Make it dense and self-contained.
  3. The user is going to want to see this same thing again tomorrow, with fresh data? → UI plugin. Read ui-plugins.md.

Read the full file on GitHub · 112 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 112 lines · 96 tokens per session scan A 311b40ac5465

Subscribe to this mod's changes

ui is a skill published in the GitHub repository tkellogg/open-strix (84 stars, last pushed 28d ago), licensed MIT. It adds 96 tokens to every session and 1,907 once invoked, about $0.0005 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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