What Is MCP and Why Would I Use It with LM-Kit.NET?
TL;DR
MCP (Model Context Protocol) is an open standard that defines how AI applications connect to external tools, data sources, and services through a unified protocol. Think of it as a universal connector for AI: instead of building custom integrations for each service, you connect to any MCP server and instantly gain access to its tools, resources, and prompts. LM-Kit.NET implements a full MCP client, letting your agents connect to the growing ecosystem of MCP servers (filesystem, GitHub, databases, Slack, and many more) with a few lines of code.
What Problem Does MCP Solve?
Without MCP, connecting an AI agent to external services means writing custom code for each integration: one adapter for your database, another for your file system, another for your CRM. If you have N models and M data sources, you end up with N×M custom connectors.
MCP standardizes this into a single protocol. Every MCP server exposes the same interface. Every MCP client speaks the same language. The result: one connection pattern for all integrations.
Without MCP: With MCP:
Agent ──► Custom code ──► DB Agent ──► MCP Client ──► Any MCP Server
Agent ──► Custom code ──► Files (one protocol) ├── Filesystem
Agent ──► Custom code ──► API ├── GitHub
Agent ──► Custom code ──► Slack ├── Database
(N×M connectors) └── Slack
(one connector each)
MCP in LM-Kit.NET
LM-Kit.NET implements a full MCP client (not a server). Your application connects to existing MCP servers and uses their capabilities through your agents:
using LMKit.Mcp;
// Connect to an MCP server over HTTP
var client = McpClientBuilder.ForHttp("https://mcp-server.example.com")
.WithBearerToken("your-token")
.WithClientInfo("MyApp", "My Application", "1.0.0")
.Build();
await client.ConnectAsync();
// All MCP tools are now available as standard ITool instances
chat.Tools.Register(client);
// The agent can now use whatever tools the MCP server provides
string response = chat.Submit("List all files in the /data directory");
What MCP Servers Provide
An MCP server can expose three types of capabilities:
| Capability | What It Is | Example |
|---|---|---|
| Tools | Callable functions the agent can invoke | read_file, create_issue, query_database |
| Resources | Data the agent can read (like a virtual file system) | Configuration files, database schemas, API documentation |
| Prompts | Pre-built prompt templates with argument substitution | "Summarize this PR", "Explain this error" |
LM-Kit.NET supports all three, plus advanced features like sampling (server requests LLM completions from the client), elicitation (server requests structured user input), progress tracking, and logging.
Transport Protocols
| Transport | How It Works | Best For |
|---|---|---|
| HTTP + SSE | HTTP POST for requests, Server-Sent Events for server notifications | Remote servers, cloud services, authenticated APIs |
| Stdio | JSON-RPC over stdin/stdout of a subprocess | Local servers (npm, Python, native executables) |
| Custom | Implement IMcpTransport for any protocol |
WebSocket, Unix sockets, custom networking |
// HTTP transport (remote server)
var client = McpClientBuilder.ForHttp("https://api.example.com/mcp")
.WithBearerToken("token")
.Build();
// Stdio transport (local subprocess)
var client = McpClientBuilder.ForStdio("npx", "@modelcontextprotocol/server-filesystem /data")
.Build();
Growing MCP Ecosystem
Thousands of MCP servers are available, covering common integrations:
| Category | Examples |
|---|---|
| File systems | Local filesystem, Google Drive, S3 |
| Developer tools | GitHub, GitLab, Jira, Linear |
| Databases | PostgreSQL, SQLite, MongoDB |
| Communication | Slack, Discord, email |
| Knowledge | Wikipedia, web search, documentation sites |
| Productivity | Notion, Todoist, calendar |
Because MCP is an open standard (now governed by the Linux Foundation), the ecosystem grows continuously.
📚 Related Content
- What MCP capabilities does LM-Kit.NET support?: Full list of supported MCP features.
- Can I connect to existing MCP servers like filesystem or GitHub?: Practical connection examples.
- What built-in tools does LM-Kit.NET provide for AI agents?: Built-in tools vs MCP tools.
- Connect to MCP Servers from Your Application: Step-by-step MCP integration guide.