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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).

91

2.21x
Quality

79%

Does it follow best practices?

Impact

93%

2.21x

Average score across 10 eval scenarios

SecuritybySnyk

Low

Low-risk findings worth noting

Fix and improve this skill with Tessl

tessl review fix ./data/05-backend-mcpbuilder/SKILL.md

The canonical home for this skill is pleaseai/mcp-dev

SKILL.md
Quality
Evals
Security

Quality

Content

71%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is a well-structured four-phase guide with concrete commands and clear references, scoring well on conciseness, actionability, and workflow clarity. Progressive disclosure is undermined by references pointing to a non-existent reference/ directory.

Suggestions

Ship the referenced ./reference/*.md bundle files (mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) or remove/inline the dangling references so navigation resolves.

Add an explicit validation checkpoint between phases (e.g., after build: 'Verify compilation passes before proceeding to evaluation') to turn the build/test step into a validate->fix->retry loop.

Trim motivational padding such as 'The quality of an MCP server is measured by how well it enables LLMs to accomplish real-world tasks.' and condense the framework-recommendation rationale.

DimensionReasoningScore

Conciseness

Mostly efficient bullets with concrete commands and URLs, but includes mild motivational padding ('The quality of an MCP server is measured by...') and a verbose framework-recommendation rationale that could be trimmed.

4 / 5

Actionability

Provides concrete executable commands (npm run build, npx @modelcontextprotocol/inspector, python -m py_compile) and specific URLs/annotations, though much implementation detail is delegated to reference files rather than shown inline.

4 / 5

Workflow Clarity

A clear four-phase sequence with numbered sub-steps and build/test steps, but it lacks an explicit validate->fix->retry feedback loop gating progression between phases.

4 / 5

Progressive Disclosure

Good section structure with one-level-deep references, but the referenced paths (./reference/*.md) do not resolve to any bundle directory present on disk, breaking navigation.

3 / 5

Total

15

/

20

Passed

Description

87%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is strong: it clearly states what the skill does and when to use it, with concrete triggers and a distinct niche. Minor specificity gains are possible by enumerating concrete actions more comprehensively.

DimensionReasoningScore

Specificity

Names the MCP-server domain and several concrete actions ('creating high-quality MCP servers', 'enable LLMs to interact with external services through well-designed tools') plus specific frameworks, but stops short of a comprehensive enumerated action list.

4 / 5

Completeness

Explicitly answers both 'what' (guide for creating high-quality MCP servers) and 'when' ('Use when building MCP servers to integrate external APIs or services') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Includes natural phrases users would say ('building MCP servers', 'integrate external APIs or services') plus framework names (FastMCP, MCP SDK), with good but not exhaustive synonym coverage.

4 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (MCP server construction) with distinct triggers and minimal overlap risk against other skills; uses compliant third-person voice.

5 / 5

Total

18

/

20

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.

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

relative_links

Relative link issues: 10 missing

Warning

Total

15

/

16

Passed

Repository
majiayu000/claude-skill-registry-data
Reviewed

Table of Contents

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