MCP Servers

Summary

MCP Servers covers protocol-specific implementation for exposing tools, resources, and prompts through the Model Context Protocol. Use it when you are building, hosting, testing, authenticating, or distributing an MCP endpoint.

• Owns: MCP architecture, transports, lifecycle, tool/resource/prompt exposure, annotations, auth integration, testing, Next.js hosting, generation, and examples.
• Does not own: general tool definition quality; see Tool Design. HTTP/OpenAPI design before wrapping it in MCP; see API Surface.
• Agent-ready means: clients can connect, inspect capabilities, call tools with schemas, receive structured results/errors, and enforce auth and safety at the server boundary.

Client or Server

A short decision rule for which side you're building: build an MCP client when your own agent needs to reach many third-party integrations and you want one protocol instead of one integration per vendor. Ship an MCP server when you want other agents - not just your own product's UI - to use your product's capabilities. The two are not mutually exclusive; a product can consume MCP servers as a client while also shipping its own.

Start Here

1. Architecture - Design focused, testable MCP servers.
2. Tool Best Practices - Implement MCP tools with clear schemas and recoverable output.
3. Resources and Prompts - Expose context and reusable prompt templates.
4. Transports - Choose stdio or streamable HTTP.
5. Authentication - Protect remote servers and validate callers.
6. Annotations - Declare read-only, destructive, and idempotent hints.
7. Testing - Validate server behavior before shipping.
8. Next.js Integration - Host MCP from a Next.js app.
9. Auto-Generation - Generate servers from existing contracts where appropriate.
10. Real-World Examples - Study production server patterns.
11. Code Execution - How a code-executing agent consumes your server as an importable library, and what that implies for tool design.

Related

1. Tool Design - Framework-neutral tool naming, schemas, and curation.
2. Authentication: MCP Authorization - OAuth discovery and client identity model.
3. Discovery: Well-Known Endpoints - Advertise MCP metadata publicly.
4. API Surface - Design the underlying HTTP contract before wrapping it.