A reference for building user-interface features with coss, a library of interface components such as buttons, dialogs, forms, menus, and tabs. It explains the correct imports, accessibility practices, and component behavior.

Building or troubleshooting coss-based controls, migrating from shadcn or Radix, and composing accessible menus, dialogs, forms, and other interactive elements.

It helps prevent integration and usability mistakes when adding coss components to an application.

coss — Skill for Claude Code and Codex by CherryHQ: A reference for building user-interface features with coss, a…

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/cherryhq/stella/coss

Any agent

npx skills add CherryHQ/stella --skill coss

Clone the repo

git clone --depth 1 https://github.com/CherryHQ/stella

Made for: Claude Code, Codex.

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/skills/cherryhq/stella/coss.svg)](https://agentmods.dev/skills/cherryhq/stella/coss)

Your own site

<a href="https://agentmods.dev/skills/cherryhq/stella/coss"><img src="https://agentmods.dev/badge/skills/cherryhq/stella/coss.svg" alt="Measured on agentmods" height="20"></a>

Per session 80 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,211 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. Scan, not verified.

Origin unknown 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	$0.00080	$0.01211
Opus 5	$0.00040	$0.00606
Sonnet 5	$0.00016	$0.00242
Haiku 4.5	$0.00008	$0.00121

Measured 4d ago against content hash 570d6c0a66ba, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

coss 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 4d 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.

.agents/skills/coss/SKILL.md · 117 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Files

What ships with it

60 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.

4d ago First seen · 117 lines · 80 tokens per session scan A 570d6c0a66ba

Subscribe to this mod's changes

coss is a skill published in the GitHub repository CherryHQ/stella (50 stars, last pushed 4d ago), licensed AGPL-3.0. It adds 80 tokens to every session and 1,211 once invoked, about $0.0004 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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