mcp-builder
Build high-quality MCP (Model Context Protocol) servers that let LLMs interact with external services through well-designed tools. Use when creating MCP servers to integrate APIs or services in Python (FastMCP) or Node/TypeScript (MCP SDK).
82
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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 strong description that clearly identifies its niche (MCP server development) and provides explicit 'Use when' guidance with framework-specific triggers. The main weakness is that the specific capabilities could be more detailed - it describes the outcome (servers that let LLMs interact) but not the specific actions the skill helps with (e.g., defining tools, handling requests, testing).
Suggestions
Add more specific actions like 'define tools, handle requests, manage authentication, test server endpoints' to improve specificity
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Names the domain (MCP servers) and mentions some actions ('Build', 'interact with external services', 'integrate APIs'), but lacks comprehensive specific actions like 'define tools', 'handle authentication', 'manage server lifecycle'. | 2 / 3 |
Completeness | Clearly answers both what ('Build high-quality MCP servers that let LLMs interact with external services through well-designed tools') and when ('Use when creating MCP servers to integrate APIs or services in Python (FastMCP) or Node/TypeScript (MCP SDK)'). | 3 / 3 |
Trigger Term Quality | Includes strong natural keywords users would say: 'MCP', 'Model Context Protocol', 'MCP servers', 'FastMCP', 'MCP SDK', 'Python', 'Node', 'TypeScript', 'APIs', 'services', 'tools', 'LLMs'. | 3 / 3 |
Distinctiveness Conflict Risk | MCP servers are a specific niche with distinct terminology (FastMCP, MCP SDK, Model Context Protocol). Unlikely to conflict with general API or server-building skills due to the specialized MCP focus. | 3 / 3 |
Total | 11 / 12 Passed |
Implementation
70%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This skill provides a well-organized, comprehensive workflow for MCP server development with excellent progressive disclosure and clear phase-based structure. Its main weaknesses are moderate verbosity in explanatory sections and deferring most executable code to reference files rather than including key snippets inline for immediate actionability.
Suggestions
Add 1-2 minimal executable code snippets inline (e.g., a basic tool registration example in TypeScript) to improve immediate actionability without requiring reference file navigation.
Trim explanatory text in sections like 'API Coverage vs. Workflow Tools' and the TypeScript recommendation rationale—Claude can infer these tradeoffs.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is reasonably efficient but includes some unnecessary explanation (e.g., explaining why TypeScript is recommended, general statements about 'quality of an MCP server'). Some sections could be tightened, though it avoids explaining basic concepts Claude would know. | 2 / 3 |
Actionability | Provides good structural guidance and links to detailed references, but the main skill file itself lacks executable code examples. Most concrete implementation details are deferred to reference files rather than shown inline with copy-paste ready snippets. | 2 / 3 |
Workflow Clarity | Excellent four-phase workflow with clear sequencing (Research → Implementation → Review/Test → Evaluation). Each phase has numbered sub-steps, and Phase 3 includes explicit validation checkpoints (build verification, testing with MCP Inspector). | 3 / 3 |
Progressive Disclosure | Well-structured overview with clear one-level-deep references to detailed guides. Reference files are clearly signaled with descriptive links and organized by phase/purpose. The documentation library section provides excellent navigation. | 3 / 3 |
Total | 10 / 12 Passed |
Validation
93%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 15 / 16 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
metadata_version | 'metadata' field is not a dictionary | Warning |
Total | 15 / 16 Passed | |
- Reviewed
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