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).
89
Quality
87%
Does it follow best practices?
Impact
88%
1.60xAverage score across 3 eval scenarios
Advisory
Suggest reviewing before use
Quality
Discovery
89%Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.
This is a solid description with excellent trigger terms and completeness, clearly specifying both the purpose and when to use the skill. The main weakness is the lack of specific concrete actions - it describes the goal but not the specific capabilities like schema definition, error handling, or tool implementation patterns.
Suggestions
Add specific concrete actions such as 'define tool schemas', 'implement request handlers', 'configure authentication', or 'structure server responses' to improve specificity.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Names the domain (MCP servers) and general purpose (enable LLMs to interact with external services), but lacks specific concrete actions like 'define tool schemas', 'handle authentication', or 'implement request handlers'. | 2 / 3 |
Completeness | Clearly answers both what ('creating high-quality MCP servers that enable LLMs to interact with external services through well-designed tools') and when ('Use when building MCP servers to integrate external APIs or services') with explicit trigger guidance. | 3 / 3 |
Trigger Term Quality | Includes good natural keywords users would say: 'MCP', 'Model Context Protocol', 'MCP servers', 'external APIs', 'services', 'Python', 'FastMCP', 'Node', 'TypeScript', 'MCP SDK' - covering multiple language variations. | 3 / 3 |
Distinctiveness Conflict Risk | MCP servers are a distinct niche with specific terminology (FastMCP, MCP SDK, Model Context Protocol) that would not conflict with general coding or API skills. | 3 / 3 |
Total | 11 / 12 Passed |
Implementation
85%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is a well-structured, comprehensive skill for MCP server development. Its strengths are excellent workflow clarity with explicit phases and validation steps, strong progressive disclosure with appropriate external references, and highly actionable guidance. The main weakness is moderate verbosity in explanatory sections that could be tightened, particularly the agent-centric design principles which explain concepts Claude already understands.
Suggestions
Condense the 'Agent-Centric Design Principles' section (1.1) to bullet points without explanatory prose - Claude understands these concepts
Remove explanatory sentences like 'The quality of an MCP server is measured by...' that don't add actionable value
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is reasonably efficient but includes some unnecessary explanation (e.g., 'The quality of an MCP server is measured by how well it enables LLMs to accomplish real-world tasks'). The agent-centric design principles section, while valuable, could be more condensed since Claude understands these concepts. | 2 / 3 |
Actionability | Provides concrete, actionable guidance throughout: specific URLs to fetch, clear file references, explicit steps for each phase, and concrete examples like the XML evaluation format. Commands and tool usage are clearly specified. | 3 / 3 |
Workflow Clarity | Excellent multi-phase workflow with clear sequencing (Phase 1-4). Includes explicit validation checkpoints (Phase 3 review, quality checklists, build verification). The warning about MCP servers hanging and safe testing approaches demonstrates good feedback loop awareness. | 3 / 3 |
Progressive Disclosure | Exemplary structure with clear overview and well-signaled one-level-deep references. Language-specific guides, best practices, and evaluation guides are appropriately externalized with clear navigation links. The Reference Files section provides excellent discoverability. | 3 / 3 |
Total | 11 / 12 Passed |
Validation
100%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 11 / 11 Passed
Validation for skill structure
No warnings or errors.
- Repository
- majiayu000/claude-skill-registry
- Commit
6213d1a
- Reviewed
Table of Contents
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