jsmcp

A meta MCP server that:

• lists MCP servers available in a preset
• connects to preset servers on startup
• exposes approved server tools to execute_code() as JavaScript libraries
• stores console output separately through log tools

Config is read from $XDG_CONFIG_HOME/jsmcp/config.json. If XDG_CONFIG_HOME is not set, it falls back to ~/.config/jsmcp/config.json.

node src/index.js
node src/index.js my-preset

The only optional argument is the preset name. If omitted, default is used.

servers uses the same local or remote format as OpenCode MCP config.

presets decides which servers are visible and which tools from each server are allowed.

Each server may also define an optional description. This is surfaced by list_servers() so agents can understand when to use that server.

Server names must be valid JavaScript identifiers because execute_code() exposes them directly as globals.

Example:

{
  "servers": {
    "math": {
      "type": "local",
      "description": "Basic arithmetic tools",
      "command": ["node", "/absolute/path/to/math-server.js"]
    },
    "docs": {
      "type": "remote",
      "description": "Documentation search and retrieval",
      "url": "https://example.com/mcp",
      "headers": {
        "Authorization": "Bearer {env:DOCS_TOKEN}"
      }
    }
  },
  "presets": {
    "default": {
      "servers": {
        "math": {
          "tools": ["add", "multiply"]
        },
        "docs": {
          "tools": ["search", "fetch_page"]
        }
      }
    },
    "math-only": ["math"]
  }
}

Accepted preset forms:

• "preset": ["server-a", "server-b"]
• "preset": { "servers": { "server-a": true } }
• "preset": { "servers": { "server-a": { "tools": ["tool1"] } } }

Tool rules:

• true, omitted tools, or "*" means all tools from that server
• tools: ["name"] restricts access to the listed tools
• false or enabled: false removes that server from the pr