mcp-builder

Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).

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npx tessl i github:boisenoise/skills-collections --skill mcp-builder

What are skills?

2.23x

Review — 80%

Does it follow best practices?

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Evaluation — 94%

↑ 2.23x

Agent success when using this skill

Validation — 11 / 11 Passed

Validation for skill structure

SKILL.md

Review

Evals

Evaluation results

100%

36%

Weather Service MCP Server

TypeScript MCP server project setup and tool registration

Criteria

Without context

With context

Server naming convention

100%

Tool naming with prefix

100%

Uses registerTool API

100%

Zod input schemas

100%

Zod strict mode

100%

Tool annotations present

100%

Correct SDK import path

100%

Project structure

100%

package.json type module

100%

tsconfig strict mode

100%

tsconfig module config

100%

Stdio transport

100%

81%

Task Management MCP Server in Python

Python MCP server with Pydantic validation and response formatting

Criteria

Without context

With context

Server naming convention

100%

FastMCP initialization

100%

Tool naming with prefix

100%

Pydantic BaseModel inputs

25%

100%

Pydantic v2 patterns

100%

ConfigDict settings

100%

Dual response format

100%

Pagination metadata

100%

Uses httpx not requests

50%

100%

Async tool functions

100%

Tool annotations

100%

Shared API utility

66%

100%

82%

52%

Remote Inventory MCP Server with HTTP Transport

Streamable HTTP transport and response truncation

Criteria

Without context

With context

Streamable HTTP transport

100%

Stateless transport config

100%

JSON response enabled

100%

New transport per request

100%

CHARACTER_LIMIT constant

80%

100%

Response truncation logic

100%

Output schema defined

structuredContent in response

100%

Actionable error messages

25%

100%

Error in result object

100%

Localhost binding

100%

41%

Multi-Domain CRM MCP Server

Multi-tool code reuse and error handling patterns

Criteria

Without context

With context

Shared API client function

100%

Centralized error handler

50%

100%

Consistent service prefix

100%

Domain-specific naming

100%

Comprehensive tool descriptions

100%

API key from environment

100%

API key validation on startup

100%

Tool annotations on all tools

100%

Shared formatting logic

100%

Error in result objects

100%

Organized file structure

100%

87%

47%

Evaluation Suite for a Library Catalog MCP Server

MCP server evaluation creation in XML format

Criteria

Without context

With context

Valid XML structure

100%

Exactly 10 questions

100%

Read-only operations

100%

Independent questions

87%

100%

Single verifiable answers

100%

Stable answers

20%

30%

Multi-tool complexity

30%

100%

No keyword giveaways

12%

62%

Human-readable answers

100%

Diverse answer types

100%

Realistic questions

90%

70%

Evaluated: 8 days ago
Agent: Claude Code

Table of Contents

Weather Service MCP Server Task Management MCP Server in Python Remote Inventory MCP Server with HTTP Transport Multi-Domain CRM MCP Server Evaluation Suite for a Library Catalog MCP Server

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