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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).

82

2.55x
Quality

Does it follow best practices?

Impact

97%

2.55x

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.

A well-sequenced, clearly validated workflow guide that delegates detail to reference files. Its main weaknesses are redundancy between inline references and the Documentation Library section, and that the referenced markdown files do not actually exist in the bundle.

Suggestions

Fix broken references: the body cites ./reference/*.md files that are absent; either add those files or point the links at the real ./scripts/ bundle (evaluation.py, example_evaluation.xml).

Remove the redundant "Documentation Library" section at the bottom, which re-lists every reference already introduced inline in the phases.

Tighten section 1.1's agent-centric design principles to only what is non-obvious, trimming restatements of concepts Claude already knows.

DimensionReasoningScore

Conciseness

The body is mostly efficient and well-structured, but the bottom "Documentation Library" section re-lists references already given inline (redundancy), and section 1.1 explains agent-centric design principles that partly restate what Claude already knows.

2 / 3

Actionability

It gives concrete commands (python -m py_compile, npm run build, timeout 5s python server.py) and a complete XML example, but the central task of implementing tools has no in-body executable code—it is delegated to reference files—so guidance is concrete yet incomplete.

2 / 3

Workflow Clarity

A clearly sequenced four-phase process (Research, Implementation, Review, Evaluations) with explicit validation checkpoints (py_compile, npm run build, Quality Checklist) and a feedback loop for error recovery.

3 / 3

Progressive Disclosure

Sections are well-organized and references are clearly signaled one level deep, but the cited files (./reference/mcp_best_practices.md, python_mcp_server.md, node_mcp_server.md, evaluation.md) do not exist—the only bundle present is ./scripts/—so navigation is broken, and the reference list is duplicated.

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 description: explicit what-and-when structure with a clear niche and natural trigger terms. The only weakness is that the named actions are somewhat abstract rather than a list of concrete operations.

DimensionReasoningScore

Specificity

It names the domain ("creating high-quality MCP servers") and a couple of actions ("interact with external services", "integrate external APIs or services"), but does not list multiple distinct concrete actions like the score-3 example; the actions stay somewhat abstract.

2 / 3

Completeness

It explicitly states what it does ("Guide for creating high-quality MCP servers...") and when to use it ("Use when building MCP servers to integrate external APIs or services..."), satisfying both halves with an explicit trigger.

3 / 3

Trigger Term Quality

Natural trigger terms a user would say are present ("building MCP servers", "integrate external APIs or services", "Python (FastMCP)", "Node/TypeScript"), giving good coverage for this domain.

3 / 3

Distinctiveness Conflict Risk

"MCP servers" is a clear, distinct niche with specific triggers (FastMCP, MCP SDK) unlikely to fire for unrelated skills.

3 / 3

Total

11

/

12

Passed

Validation

87%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

relative_links

Relative link issues: 14 missing

Warning

Total

14

/

16

Passed

Repository
davepoon/buildwithclaude
Reviewed

Table of Contents

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