create-mcp-app

create-mcp-app is a skill for Claude Code, Codex from usalu/semio. It costs 77 tokens per session (1,846 once invoked), scanned A, original, AGPL-3.0.

A guide for creating MCP Apps, which add interactive user interfaces to tools exposed through the Model Context Protocol. It covers registering interface resources, managing the app lifecycle, and connecting the interface to its host.

In plain words
What is it for?
Scaffolding an MCP App, adding a UI to an MCP tool, registering UI resources, handling app lifecycle events, and integrating with an MCP host.
Why use it?
It helps developers understand the project structure and integration steps needed when an MCP tool needs a visible interactive interface.

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/usalu/semio/create-mcp-app
Any agent
npx skills add usalu/semio --skill create-mcp-app
Clone the repo
git clone --depth 1 https://github.com/usalu/semio

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.

agentmods badge for create-mcp-app

README.md
[![agentmods](https://agentmods.dev/badge/skills/usalu/semio/create-mcp-app.svg)](https://agentmods.dev/skills/usalu/semio/create-mcp-app)
Your own site
<a href="https://agentmods.dev/skills/usalu/semio/create-mcp-app"><img src="https://agentmods.dev/badge/skills/usalu/semio/create-mcp-app.svg" alt="Measured on agentmods" height="20"></a>
Per session 77 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,846 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.

ModelPer sessionOnce invoked
Fable 5 $0.00077 $0.01846
Opus 5 $0.00039 $0.00923
Sonnet 5 $0.00015 $0.00369
Haiku 4.5 $0.00008 $0.00185

Measured 4d ago against content hash fb8897196a6e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

create-mcp-app 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/create-mcp-app/SKILL.md · 185 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

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. 4d ago First seen · 185 lines · 77 tokens per session scan A fb8897196a6e

Subscribe to this mod's changes

create-mcp-app is a skill published in the GitHub repository usalu/semio (21 stars, last pushed today), licensed AGPL-3.0. It adds 77 tokens to every session and 1,846 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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