MCP Server - JavaScript SDK

What is MCP Server - JavaScript SDK?

MCP Server - JavaScript SDK is an unofficial JavaScript SDK for the Model Context Protocol. It allows developers to define server prompts, resources, and tools in separate JavaScript files and create a MCP server instance.

How to use MCP Server - JavaScript SDK?

Create files defining prompts, resources, and tools (e.g., prompts.js, resources.js, tools.js). Then import them into a server file and instantiate MCP with an info object (name, version), plus the prompts, resources, and tools objects.

Key features of MCP Server - JavaScript SDK

• Define prompts with description, arguments, and message content
• Define resources by URI and MIME type
• Define tools with description, async handler, and JSON schema for parameters
• Simple server instantiation with new MCP(infos, prompts, resources, tools)
• Logs saved to system-specific user log directories

Use cases of MCP Server - JavaScript SDK

• Building a custom MCP-compatible server with custom prompts, resources, and tools
• Rapid prototyping of MCP services using JavaScript/Node.js
• Integrating MCP with existing JavaScript codebases
• Educational experimentation with the Model Context Protocol

FAQ from MCP Server - JavaScript SDK

What is MCP Server - JavaScript SDK?

It is an unofficial JavaScript SDK for the Model Context Protocol that lets you define prompts, resources, and tools and run a server.

How do I define prompts?

Export a prompts object from a JavaScript file. Each key is the prompt name; value contains description, arguments, and messages with role and content.

How do I define resources?

Export a resources object where each key is a resource name and value has uri and mimeType fields.

How do I define tools?

Export a tools object. Each tool has description, an async handler function, and a schema object describing parameters.

Where are server logs stored?

Logs are stored in the user system logs directory: ~/.local/share/logs (Linux), ~/Library/Logs (macOS), or %USERPROFILE%\AppData\Local\Logs (Windows).