Mysti is a VS Code extension that lets multiple AI coding providers and agents work alone or together on software tasks, including collaborative brainstorming and solution synthesis. It is for developers who want to use providers such as Claude Code, Codex, Gemini, Copilot, or local models within a coding workspace. The catalogue instruction supports using Mysti's agent collaboration workflow.
Borrowing it
Nothing to install: this file belongs to DeepMyst/Mysti. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/DeepMyst/Mysti/main/CLAUDE.mdgit clone --depth 1 https://github.com/DeepMyst/MystiWrote 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.
[](https://agentmods.dev/instructions/deepmyst/mysti/claude-md)<a href="https://agentmods.dev/instructions/deepmyst/mysti/claude-md"><img src="https://agentmods.dev/badge/instructions/deepmyst/mysti/claude-md/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.
<a href="https://agentmods.dev/instructions/deepmyst/mysti/claude-md"><img src="https://agentmods.dev/badge/instructions/deepmyst/mysti/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.12020 | $0.12020 |
| Opus 5.5 | $0.04808 | $0.04808 |
| Sonnet 5.5 | $0.02404 | $0.02404 |
| Haiku 4.5 | $0.01202 | $0.01202 |
Grade E, and why
Mysti CLAUDE.md scanned grade E with 4 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 23d 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.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
The terminal lets sudo prompt and shows the user the command it is prompting for. Downloads and executes remote codehighSupply chain
curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.
- **Cursor** — macOS/Linux: `curl https://cursor.com/install -fsS | bash`; Windows (PowerShell): `irm 'https://cursor.com/install?win32=true' | iex` (binary is `cursor-agent`/`agent`; login: `agent login`) Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
- `npm i -g @continuedev/cli` (Continue — binary `cn`; models/keys configured in `~/.continue/config.yaml`, first interactive run walks through onboarding) Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
- **Cursor** — macOS/Linux: `curl https://cursor.com/install -fsS | bash`; Windows (PowerShell): `irm 'https://cursor.com/install?win32=true' | iex` (binary is `cursor-agent`/`agent`; login: `agent login`) How it starts
The opening of the file, as written. The whole thing — 661 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Project Overview
Mysti is a VSCode extension providing a unified AI coding assistant interface supporting 15 AI backends (Claude Code, OpenAI Codex, Google Gemini, Cline, GitHub Copilot, Cursor, OpenClaw, OpenCode, Qwen Code, Ollama, LocalAI, Hermes, Continue, OpenRouter, and Kimi Code). It features sidebar/tab chat panels, conversation persistence, multi-agent brainstorm mode (any 2 of 15 agents with 5 collaboration strategies), autonomous mode with safety classification, @-mention agent routing, permission controls, plan selection, context compaction, and a three-tier agent loading system for personas and skills.
Build Commands
npm run compile # Production build: generates the core-agent manifest, then webpack
npm run watch # Dev build with watch mode (also regenerates the manifest first)
npm run lint # check-provider-literals + core-manifest --check + eslint (src + media)
npm run typecheck # TypeScript contract check
npm run test # Vitest unit and Chromium browser suites
npm run test:vscode # Extension-host integration tests (tests-vscode/, real VS Code, mocha)
npm run build:core-manifest # Regenerate src/generated/coreAgentManifest.ts from resources/agents/core
npm run sync-agents # Sync plugins from wshobson/agents repo
npm run sync-agents:force # Force sync (ignores 24h cache)
npm run package # vsce package (pinned vsce 3.9.2)
npm run check:package -- path/to.vsix # Verify the built archive
Two webpack bundles compile the same tsconfig.json (via tsRule(instance) in
webpack.config.js): the extension host bundle dist/extension.js (target
node, CommonJS2, entry src/extension.ts) and the canvas webview renderer
dist/canvasWebview.js (target web, ESM, entry src/webview/canvas/index.ts).
The canvas bundle deliberately has no vscode/node externals, so it can only
import real bundled code shared from the host (CanvasSandbox, protocol.ts,
DocPatch).
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.
- 23d ago Changed · +14 lines · +298 tokens per session 35a08e9e7c0b
- 24d ago Changed · +396 lines · +8,329 tokens per session scan C → E 356b1e170507
- 1mo ago First seen · 251 lines · 3,393 tokens per session scan C 3d2d82b66b35
Mysti CLAUDE.md is an instructions file published in the GitHub repository DeepMyst/Mysti (1,147 stars, last pushed 14d ago), licensed Apache-2.0. It adds 12,020 tokens to every session, about $0.0481 per session on Opus 5.5. A static security scan graded it E with 4 findings (asks for root, downloads and executes remote code, reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deno copilot-instructions.md
Copilot instructions for denoland/deno, covering deno development guide for github copilot, network access, high level overview, key directories and key files to understand first.