Full comparison table

All six frameworks score in the top 1.4% of 25,750 indexed repositories. The most striking finding: community-built frameworks dominate the top spots. mark3labs/mcp-go ranks #4 globally, ahead of the official TypeScript SDK by 265 positions.

Score = AgentRank composite (0–100). Rank = position among 25,750 indexed repos. Dep. = inbound GitHub package dependents. Close% = closed_issues / total_issues. Data from March 19, 2026 crawl.

mcp-go — score 96.09, rank #4

mark3labs/mcp-go is the highest-scored MCP server framework in the index and the top Go implementation by a wide margin. At score 96.09 and global rank #4 across all 25,750 indexed repositories, it sits ahead of nearly every tool in the ecosystem regardless of language.

The key data points: 2,963 inbound dependents, 170 contributors, and a 90% issue close rate — the highest among all six frameworks. That close rate is a signal of operational discipline: the maintainers resolve issues consistently and quickly. Combined with 8,353 stars and a last commit on March 11, 2026, this is an actively maintained project with deep ecosystem roots.

mcp-go predates Anthropic's official Go SDK by over a year, which explains its 2.85x dependents advantage (2,963 vs 1,040 for the official go-sdk). Developers who needed Go MCP support in 2024 and early 2025 went to mcp-go because it was the only production-ready option. That installed base compounds: each dependent is a real repository that will need to be migrated if the maintainer ever switches libraries.

The framework uses a straightforward declarative API with tools, resources, and prompts registered via builder patterns. It handles stdio and SSE transports, and includes a test client for integration testing — a feature the official Go SDK is still maturing.

FastMCP (Python) — score 95.61, rank #6

PrefectHQ/fastmcp is the de facto standard for Python MCP server development. Score 95.61, global rank #6, and 7,819 inbound dependents — the highest dependents count of any framework in this comparison by a factor of 2.6x.

FastMCP wraps the official modelcontextprotocol/python-sdk with a FastAPI-style decorator API. You write @mcp.tool() and FastMCP infers the JSON schema from Python type hints. Compared to the official SDK's explicit type definitions and asyncio boilerplate, this eliminates roughly 70% of the code you'd otherwise write to register a tool.

The project started as a solo effort by jlowin and was later adopted by Prefect (the workflow orchestration company), bringing institutional maintenance without disrupting the community character. The result is 208 contributors, an 84% issue close rate, and a commit as recent as March 17, 2026 — the most recent update of any framework in this list.

The 7,819 dependents number deserves context: the official Python SDK shows 0 dependents in our index. This doesn't mean nobody uses the official SDK — it means most Python developers install fastmcp directly, pulling in the official SDK as a transitive dependency. When fastmcp is the entry point, it's fastmcp that accumulates the dependents signal.

Official Go SDK — score 92.77, rank #16

modelcontextprotocol/go-sdk is Anthropic's official Go implementation, released in early 2026. At score 92.77 and rank #16, it's already in the top 0.1% of all indexed repositories despite being newer than mcp-go.

The 96 contributors and 87% issue close rate are strong signals for a young project — the Anthropic team is clearly staffing it properly. With 1,040 inbound dependents already, it's picking up adoption from teams who want spec-guaranteed behavior or prefer Anthropic's official support posture.

The key trade-off: mcp-go has a 2.9-point score advantage (96.09 vs 92.77) and 2.85x more dependents, representing years of established adoption. The official SDK offers spec parity guarantees that a community library technically can't make. For teams with compliance requirements or those contributing to the MCP specification itself, the official SDK is the right call.

FastMCP (TypeScript) — score 89.71, rank #41

punkpeye/fastmcp brings the FastMCP developer experience — decorator-style tool registration, auto-schema generation from TypeScript types — to the TypeScript ecosystem. Score 89.71, rank #41, 1,303 inbound dependents.

With 2,999 stars and 56 contributors, it's a smaller community than its Python counterpart but growing. The 69% issue close rate is the lowest among the community frameworks here, though still reasonable for a project of its age. The last commit on March 6, 2026 shows active maintenance.

The case for punkpeye/fastmcp over the official TypeScript SDK is the same as in Python: less boilerplate, faster iteration, more ergonomic API. The case against: 1,303 dependents vs the TypeScript SDK's 0 recorded (actual usage is higher, but not through fastmcp's transitive chain). For TypeScript teams already familiar with the official SDK's patterns, the migration cost may not be worth the ergonomic gain.

Official Python & TypeScript SDKs

modelcontextprotocol/python-sdk — score 74.90, rank #262

The official Python SDK has 22,124 stars and 181 contributors — larger star count than FastMCP — but scores 20.71 points lower. The gap is almost entirely explained by the dependents signal: 0 recorded vs FastMCP's 7,819. The official SDK also carries a 65% issue close rate, reflecting the reality that many open issues are spec-level discussions that stay open for governance reasons.

This isn't a weak project. Score 74.90 and rank #262 out of 25,750 puts it in the top 1%. But the AgentRank model accurately reflects ecosystem behavior: Python developers primarily reach for FastMCP, not the official SDK, when building MCP servers.

modelcontextprotocol/typescript-sdk — score 70.73, rank #336

The official TypeScript SDK (@modelcontextprotocol/sdk on npm) is the reference implementation for TypeScript. Score 70.73, rank #336, 11,842 stars, 152 contributors. The 58% issue close rate is the lowest in this list — partly spec governance, partly the larger surface area of a reference implementation. Zero recorded dependents reflects the same transitive dependency dynamic as the Python SDK.

Use the official TypeScript SDK when you need complete protocol coverage, are building tooling that targets multiple MCP clients, or are contributing to spec development. The official SDK exposes transport-layer internals that community frameworks abstract away.

Decision guide: which framework to pick

The pattern holds across all three languages: community frameworks win on application development, official SDKs win on protocol-level infrastructure work. Most developers are building application-layer MCP servers, which is why the community frameworks dominate the AgentRank top 10.

Quick-start code

mcp-go — the minimal Go server

go get github.com/mark3labs/mcp-go

package main

import (
    "context"
    "fmt"
    "github.com/mark3labs/mcp-go/mcp"
    "github.com/mark3labs/mcp-go/server"
)

func main() {
    s := server.NewMCPServer("My Server", "1.0.0")

    addTool := mcp.NewTool("add",
        mcp.WithDescription("Add two numbers"),
        mcp.WithNumber("a", mcp.Required()),
        mcp.WithNumber("b", mcp.Required()),
    )

    s.AddTool(addTool, func(ctx context.Context, req mcp.CallToolRequest) (*mcp.CallToolResult, error) {
        a := req.Params.Arguments["a"].(float64)
        b := req.Params.Arguments["b"].(float64)
        return mcp.NewToolResultText(fmt.Sprintf("%g", a+b)), nil
    })

    server.ServeStdio(s)
}

FastMCP — the minimal Python server

pip install fastmcp

from fastmcp import FastMCP

mcp = FastMCP("My Server")

@mcp.tool()
def add(a: float, b: float) -> float:
    """Add two numbers."""
    return a + b

if __name__ == "__main__":
    mcp.run()

FastMCP TypeScript — the minimal TypeScript server

npm install fastmcp

import { FastMCP } from "fastmcp";
import { z } from "zod";

const server = new FastMCP({ name: "My Server", version: "1.0.0" });

server.addTool({
  name: "add",
  description: "Add two numbers",
  parameters: z.object({ a: z.number(), b: z.number() }),
  execute: async ({ a, b }) => String(a + b),
});

server.start({ transportType: "stdio" });

Official TypeScript SDK — the minimal server

npm install @modelcontextprotocol/sdk

import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { CallToolRequestSchema } from "@modelcontextprotocol/sdk/types.js";

const server = new Server({ name: "My Server", version: "1.0.0" });

server.setRequestHandler(CallToolRequestSchema, async (request) => {
  if (request.params.name === "add") {
    const { a, b } = request.params.arguments as { a: number; b: number };
    return { content: [{ type: "text", text: String(a + b) }] };
  }
  throw new Error("Unknown tool");
});

const transport = new StdioServerTransport();
await server.connect(transport);

The boilerplate difference is visible. Community frameworks (mcp-go, FastMCP) register tools declaratively with type inference. The official SDKs require explicit schema definitions and request handler dispatch. Neither is wrong — it's a trade-off between expressiveness and protocol transparency.