mcp.zig

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Getting Started ​

Welcome to mcp.zig — the first comprehensive Model Context Protocol (MCP) library for Zig!

Why mcp.zig?

While MCP has official SDKs for TypeScript, Python, and other languages, Zig currently lacks proper MCP support. mcp.zig fills this gap, bringing the power of MCP to the Zig ecosystem.

What You'll Learn ​

In this guide, you'll learn how to:

  1. Install mcp.zig as a dependency
  2. Create a simple MCP server
  3. Register tools, resources, and prompts
  4. Connect to an MCP server as a client

Prerequisites ​

Before you begin, make sure you have:

  • Zig 0.15.0 or later installed
  • Basic familiarity with Zig programming language

Quick Installation ​

Run the following command in your project directory:

bash
zig fetch --save https://github.com/muhammad-fiaz/mcp.zig/archive/refs/tags/0.0.1.tar.gz

Then in your build.zig:

zig
const mcp_dep = b.dependency("mcp", .{
    .target = target,
    .optimize = optimize,
});

exe.root_module.addImport("mcp", mcp_dep.module("mcp"));

Your First MCP Server ​

Here's a minimal example of an MCP server:

zig
const std = @import("std");
const mcp = @import("mcp");

pub fn main() void {
    // Run the application logic
    run() catch |err| {
        // Report error with link to issue tracker if needed
        mcp.reportError(err);
    };
}

fn run() !void {
    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
    defer _ = gpa.deinit();
    const allocator = gpa.allocator();

    // Check for library updates in background (recommended)
    if (mcp.report.checkForUpdates(allocator)) |t| t.detach();

    // Create a server
    var server = mcp.Server.init(.{
        .name = "hello-server",
        .version = "1.0.0",
        .allocator = allocator,
    });
    defer server.deinit();

    // Add a simple tool
    try server.addTool(.{
        .name = "hello",
        .description = "Says hello to someone",
        .handler = helloHandler,
    });

    // Run the server (blocks until shutdown)
    try server.run(.stdio);
}

fn helloHandler(
    allocator: std.mem.Allocator,
    args: ?std.json.Value,
) mcp.tools.ToolError!mcp.tools.ToolResult {
    const name = mcp.tools.getString(args, "name") orelse "World";

    const message = try std.fmt.allocPrint(allocator, "Hello, {s}!", .{name});

    return mcp.tools.ToolResult{
        .content = &.{mcp.Content.createText(message)},
    };
}

Next Steps ​

Now that you have the basics, explore:

Official MCP Resources ​