mcp-server-ts

TypeScript MCP Server Builder

Build MCP (Model Context Protocol) servers in TypeScript by referencing code snippets from the official Everything reference server.

How It Works

1. Browse the snippet catalog below or in snippets/
2. Copy the snippets you need into your project
3. Customize the copied code for your use case
4. Register your tools/resources/prompts with the server

Snippets are bundled in this skill's snippets/ directory.

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Quick Start Decision Trees

What MCP Primitive Should I Use?

Need to perform actions with side effects?
  └─> Is it a long-running operation (>2-3 seconds)?
      └─> Use TASKS (async execution with polling)
          Examples: Research queries, data processing, report generation
  └─> Is it quick and synchronous?
      └─> Use TOOLS (model-controlled)
          Examples: API calls, file operations, computations

Need to expose data for LLM context?
  └─> Is data relatively static or URI-addressable?
      └─> Use RESOURCES (application-controlled)
          Examples: file contents, database records, API responses
  └─> Need parameterized access patterns?
      └─> Use Resource Templates with URI variables
          Example: myapp://users/{userId}/profile

Need user-initiated commands/slash commands?
  └─> Use PROMPTS (user-controlled)
      Examples: /summarize, /translate, /analyze

What Transport Should I Use?

Local integration (subprocess, CLI, Claude Desktop)?
  └─> Use stdio transport (default)

Remote service, multi-client, or web deployment?
  └─> Use Streamable HTTP transport

Logging with stdio transport: Never use console.log() in stdio servers - it writes to stdout, which is reserved for MCP protocol messages and will break communication. Use console.error() for all diagnostic output (it writes to stderr).

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Phase 1: Research

1.1 Identify Your Integration

Before writing code, understand:

• What API/service are you integrating?
• What operations do users need to perform?
• What data should be exposed to the LLM?