charming-mcp: Instructions file for Codex

AGENTS.md

charming-mcp AGENTS.md is an instructions file for Codex, OpenCode from tambo-labs/charming-mcp. It costs 1,373 tokens per session, scanned A, original, MIT.

Project instructions for using Charming, a hosted service that creates, hosts, and updates interactive web apps through an MCP connection. MCP is a standard way for an AI client to call external tools.

In plain words
What is it for?
Use them to connect supported AI clients to Charming, request interactive apps, and understand how the resulting live URLs and persistent storage work.
Why use it?
They explain how to connect to the remote service and what happens when an app is created, so the agent does not try to clone or run it locally.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions Claude Code; mentions AGENTS.md; mentions Codex.

This is tambo-labs/charming-mcp's own configuration. It tells Codex and OpenCode how to work on charming-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything charming-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to tambo-labs/charming-mcp. 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/tambo-labs/charming-mcp/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/tambo-labs/charming-mcp

Made for: Codex, OpenCode.

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 charming-mcp AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/tambo-labs/charming-mcp/agents-md.svg)](https://agentmods.dev/instructions/tambo-labs/charming-mcp/agents-md)
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<a href="https://agentmods.dev/instructions/tambo-labs/charming-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/tambo-labs/charming-mcp/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,373 This file is loaded in full into every session.
When invoked 1,373 The same file — it is already loaded in full.
Security scan A 1 finding. 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 5.1 $0.01373 $0.01373
Opus 5 $0.00687 $0.00687
Sonnet 5 $0.00275 $0.00275
Haiku 4.5 $0.00137 $0.00137

Measured 5d ago against content hash 323480807735, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

charming-mcp AGENTS.md scanned grade A with 1 finding 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 5d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- **MCP tools** (preferred): when Charming tools such as `create_app` and `update_app` are available, build with them directly. Do not use `curl`, `fetch`, or the raw HTTP API for app creation.
Origin

Copies of this mod

1 near-identical copy found in the catalogue:

AGENTS.md · 59 lines

How it starts

The opening of the file, as written. The whole thing — 59 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Instructions for AI coding agents working with Charming.

Charming is a hosted MCP server that generates, hosts, and updates interactive web apps. Ask it to build an app and you get back a live URL with persistent storage in seconds. The app stays live at that URL, and any MCP client can keep using and updating it.

Connect first

Charming is remote and hosted; there is nothing to clone, build, or run. Add the endpoint to your MCP settings:

Client Endpoint
Claude, Claude Code, Cursor, Codex, Gemini CLI, and most MCP clients https://charm.ing/mcp
ChatGPT the Charming listing in the ChatGPT Apps directory is one click; https://charm.ing/mcp/chatgpt is the Developer Mode fallback
Codex (plugin) codex plugin marketplace add https://github.com/tambo-labs/charming-codex-plugin.git
Cursor https://charm.ing/mcp (plus drop .cursor/rules/charming.mdc into your project)

The MCP endpoints always require a bearer token; OAuth with Dynamic Client Registration bootstraps one automatically, with no API key to paste. Anonymous creation with no token is available on the HTTP path only, and an unclaimed app expires after 7 days. Auth guide: usecharming.com/auth.md. Per-client paste-strings: usecharming.com/clients.txt.

Two authoring paths

  • MCP tools (preferred): when Charming tools such as create_app and update_app are available, build with them directly. Do not use curl, fetch, or the raw HTTP API for app creation.
  • HTTP API (fallback): only when MCP tools are unavailable and you have outbound HTTP access. Follow usecharming.com/build-http.md.

Build flow

  1. Read usecharming.com/start.md, then the surface-specific starter: build-mcp.md or build-http.md.
  2. Read usecharming.com/design.md before writing any UI, so the app avoids the generic-AI-app look.
  3. Create the first version, hand back the app URL and app_id, then offer one concrete next iteration before editing again.
  4. If a host does not render the app inline, share the URL; never claim it rendered inline unless it did.
  5. Hit a limitation? Call submit_feedback instead of working around it silently.

Read the full file on GitHub · 59 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.

  1. 5d ago First seen · 59 lines · 1,373 tokens per session scan A 323480807735

Subscribe to this mod's changes

charming-mcp AGENTS.md is an instructions file published in the GitHub repository tambo-labs/charming-mcp (1 stars, last pushed 14d ago), licensed MIT. It adds 1,373 tokens to every session, about $0.0069 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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