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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).

81

1.60x
Quality

Does it follow best practices?

Impact

88%

1.60x

Average score across 3 eval scenarios

SecuritybySnyk

Advisory

Suggest reviewing before use

SKILL.md
Quality
Evals
Security

Quality

Content

62%

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 process with explicit review and test checkpoints, but it is hampered by missing bundle files (every referenced path 404s), no inline executable code, and some redundancy. Progressive disclosure and actionability are the weakest dimensions because the skill depends entirely on reference files that are absent.

Suggestions

Create the missing ./reference/ bundle files (mcp_best_practices.md, python_mcp_server.md, node_mcp_server.md, evaluation.md) — every referenced path in the body is broken, which is the core progressive-disclosure defect.

Add at least one complete, executable tool example inline in SKILL.md instead of deferring all code to the (missing) reference files, so the body is actionable on its own.

Deduplicate the reference listings (they appear in both Phase 1.4 and the "Reference Files" section) and trim the Overview paragraph that restates the frontmatter description.

DimensionReasoningScore

Conciseness

The ~320-line body restates the description in the Overview and lists the reference files twice (Phase 1.4 and the "Reference Files" section); it is mostly efficient but could be tightened, matching the score-2 anchor rather than the lean score-3 anchor.

2 / 3

Actionability

It gives concrete commands ("python -m py_compile", "npm run build", "timeout 5s python server.py") and patterns (Zod ".strict()", tool annotation hints), but no complete executable code example appears in the body — all examples are deferred to the reference files, so guidance is incomplete.

2 / 3

Workflow Clarity

A clear four-phase sequence (Research, Implementation, Review, Evaluations) with explicit review (3.1), test/build (3.2), and quality-checklist (3.3) checkpoints; not score 2 because checkpoints are explicit, though error-recovery feedback loops are implicit rather than spelled out.

3 / 3

Progressive Disclosure

References are well-signaled and one level deep ("./reference/mcp_best_practices.md", "python_mcp_server.md", "node_mcp_server.md", "evaluation.md"), but none of these bundle files exist, so navigation is broken and the disclosure does not actually function — matching score 2 rather than 3.

2 / 3

Total

9

/

12

Passed

Description

90%

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

A strong, third-person description with an explicit "Use when" trigger and good natural keyword coverage for the MCP niche. It is held back only on specificity, since the actions described restate one operation rather than enumerating several distinct concrete capabilities.

DimensionReasoningScore

Specificity

Quotes "creating high-quality MCP servers" and "building MCP servers to integrate external APIs or services" name the domain and main action, but rephrase one operation rather than listing multiple distinct concrete actions, matching the score-2 anchor.

2 / 3

Completeness

It answers "what" ("Guide for creating high-quality MCP servers...") and "when" with an explicit trigger ("Use when building MCP servers to integrate external APIs or services...").

3 / 3

Trigger Term Quality

Natural terms a user would say are well covered: "MCP servers", "external APIs or services", "Python (FastMCP)", and "Node/TypeScript (MCP SDK)".

3 / 3

Distinctiveness Conflict Risk

"MCP (Model Context Protocol) servers" plus framework-specific "FastMCP" and "MCP SDK" carve a clear niche unlikely to trigger for unrelated skills.

3 / 3

Total

11

/

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.

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

relative_links

Relative link issues: 14 missing

Warning

Total

15

/

16

Passed

Repository
majiayu000/claude-skill-registry
Reviewed

Table of Contents

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