Vulcanus — Claude Code MCP server: what it does, how to install
Keeps project context in a Git-versioned Markdown vault. Your coding agent recalls rules and decisions via MCP without reading endless logs.
claude mcp add vulcanus -- npx -y @sunsato/vulcanusWhat Vulcanus does
Vulcanus replaces oversized instruction files with an organized Markdown knowledge base tracked by Git. Instead of parsing the entire project memory on every query, an assistant reads the Recall Map, opens a concise Capsule note, and navigates into specific decisions or rules only when needed. It can also generate the initial vault structure directly from previous chat exports of Claude Code, Cursor, Codex, or ChatGPT.
The tool requires Node.js version 22.12 or higher. Keep in mind that project visibility tags like private act as agent instructions rather than cryptographic access control. The vulcanus doctor command verifies internal links, keeping stale references from quietly breaking context retrieval.
Everything runs locally on your machine with no third-party accounts. Global installation ensures that repository skills and MCP commands locate the executable inside your system PATH.
What it helps with
- maintain architectural decisions across fresh agent coding sessions
- split project constraints into modular Markdown notes
- extract context from Cursor, Codex, or ChatGPT conversation dumps
- validate internal links across the memory vault with vulcanus doctor
Example prompts for the agent
- Recall the architectural decisions and constraints for this project
- Run vulcanus stats to check token reduction in the current vault
- Verify all project capsule links and report missing references
How to install Vulcanus
Platform CLI
claude mcp add vulcanus -- npx -y @sunsato/vulcanusPlatform CLI
codex mcp add vulcanus -- npx -y @sunsato/vulcanusConfig file
{
"mcpServers": {
"vulcanus": {
"command": "npx",
"args": [
"-y",
"@sunsato/vulcanus"
]
}
}
}Config file
{
"servers": {
"vulcanus": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@sunsato/vulcanus"
]
}
}
}Platform CLI
gemini mcp add vulcanus npx -y @sunsato/vulcanusStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Vulcanus
How to install Vulcanus in Claude Code?
Run claude mcp add vulcanus -- npx -y @sunsato/vulcanus in your terminal. For skills and hooks to work properly across repositories, also install it globally via npm install -g @sunsato/vulcanus.
What does Vulcanus do?
It provides a structured, Git-backed memory vault exposed over MCP. Agents fetch relevant capsules and rules on demand instead of loading massive instruction prompts on every turn.
What are the system requirements for Vulcanus?
You need Node.js 22.12 or newer on your machine. Vulcanus runs locally without external accounts or cloud databases.
