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jbvc/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).

63

Quality

79%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

Overview
Quality
Evals
Security
Files

Quality

Content

57%

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-organized high-level guide with strong progressive disclosure and clear phased workflow structure. Its main weaknesses are the lack of concrete, executable code examples within the SKILL.md itself (most actionability is deferred to reference files) and some redundancy between the phased workflow and the Reference Files section. Adding inline code snippets and explicit validation/error-recovery steps would significantly improve it.

Suggestions

Add at least one concrete, executable code example inline (e.g., a minimal TypeScript tool registration with Zod schema) so the SKILL.md itself is actionable without loading reference files.

Add explicit validation checkpoints with feedback loops in Phase 3, e.g., 'If build fails: check type errors, fix, rebuild. Only proceed to testing when build succeeds.'

Remove or consolidate the Reference Files section at the bottom, as it largely duplicates links and descriptions already provided inline within the phases.

DimensionReasoningScore

Conciseness

The content is reasonably organized but includes some unnecessary explanation (e.g., explaining why TypeScript is recommended with multiple justifications, explaining what MCP is). Some sections like the Reference Files section largely duplicate information already presented in the phases, adding redundancy.

2 / 3

Actionability

The skill provides structured guidance and references to external guides, but the SKILL.md itself contains very little executable code or copy-paste-ready commands. Most concrete implementation details are deferred to reference files. The inline guidance is more descriptive ('Create shared utilities', 'Implement tools') than instructive with specific code examples.

2 / 3

Workflow Clarity

The four-phase workflow is clearly sequenced and logically organized. However, validation checkpoints are weak—Phase 3 mentions running build and testing but lacks explicit feedback loops (e.g., what to do if build fails, how to verify tools work correctly before proceeding). For a process involving server development and deployment, the absence of clear validate-fix-retry loops is notable.

2 / 3

Progressive Disclosure

The content is well-structured as an overview with clear, well-signaled one-level-deep references to language-specific guides, best practices, evaluation guide, and SDK documentation. Navigation is easy with emoji markers and descriptive link text. The Reference Files section provides a useful summary of what each linked resource contains.

3 / 3

Total

9

/

12

Passed

Description

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 that clearly identifies its niche (MCP server development) and provides explicit 'Use when' guidance with relevant technology keywords. Its main weakness is that the 'what' portion is somewhat high-level—it could benefit from listing more specific concrete actions like defining tools, configuring transports, or handling authentication. Overall, it performs well for skill selection purposes.

Suggestions

Add more specific concrete actions to the 'what' portion, e.g., 'defining tools and resources, configuring transports, handling authentication, structuring server projects'.

DimensionReasoningScore

Specificity

The description names the domain (MCP servers) and a general action ('creating high-quality MCP servers that enable LLMs to interact with external services'), but doesn't list multiple specific concrete actions like defining tools, handling authentication, setting up transport layers, etc.

2 / 3

Completeness

Clearly answers both 'what' (creating 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, whether 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', 'external APIs', 'Python', 'Node', 'TypeScript', and 'tools'. These cover the main variations a user might use when asking about this topic.

3 / 3

Distinctiveness Conflict Risk

MCP server development is a very specific niche with distinct trigger terms (MCP, Model Context Protocol, FastMCP, MCP SDK). It's unlikely to conflict with general coding skills or other integration-related skills.

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.

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Reviewed

Table of Contents