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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

Does it follow best practices?

Impact

93%

2.21x

Average score across 10 eval scenarios

SecuritybySnyk

Advisory

Suggest reviewing before use

SKILL.md
Quality
Evals
Security

Quality

Content

57%

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

The body is concise and well-sequenced, but actionability is undermined by descriptive (non-executable) tool-implementation guidance and progressive disclosure is broken because the referenced ./reference/ files are missing from the bundle.

Suggestions

Add at least one complete, executable tool-registration code example in the body so the core implementation step is copy-paste ready rather than descriptive.

Provide the referenced ./reference/*.md files (mcp_best_practices, node_mcp_server, python_mcp_server, evaluation) or fix the paths to match the actual bundle structure.

Add an explicit validate→fix→retry feedback loop in the tool-implementation phase (Phase 2), mirroring the validation rigor shown in Phase 3.

DimensionReasoningScore

Conciseness

Lean, list-driven guidance that assumes Claude's competence—concrete URLs and commands with no padding explaining basic concepts; only a few slightly verbose rationale lines.

3 / 3

Actionability

Provides concrete commands and URLs, but the core tool-implementation section is descriptive lists ('Use Zod', 'Define outputSchema', 'async/await') with no executable code example in the body—delegating all code to referenced files.

2 / 3

Workflow Clarity

The four-phase sequence is clear and Phase 3 has build/Inspector checkpoints, but the fragile tool-implementation phase lacks an explicit validate→fix→retry feedback loop.

2 / 3

Progressive Disclosure

The body references ./reference/*.md files (mcp_best_practices, node_mcp_server, python_mcp_server, evaluation) that do not exist in the bundle—only a scripts/ dir is present—so navigation is broken for a 230-line skill.

1 / 3

Total

8

/

12

Passed

Description

85%

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 specific, complete with an explicit 'Use when' trigger, and clearly distinct. Its only weakness is trigger-term breadth—missing several natural phrasings a user might say.

DimensionReasoningScore

Specificity

Lists multiple concrete actions—'creating high-quality MCP servers', 'interact with external services through well-designed tools', and 'integrate external APIs or services'—rather than vague language.

3 / 3

Completeness

Explicitly answers both what ('creating high-quality MCP servers that enable LLMs to interact with external services') and when ('Use when building MCP servers to integrate external APIs or services').

3 / 3

Trigger Term Quality

'Use when building MCP servers to integrate external APIs or services' provides relevant natural terms, but coverage lacks common variations like 'Model Context Protocol server' or 'tool server'.

2 / 3

Distinctiveness Conflict Risk

MCP server building is a clear, specialized niche with explicit triggers, making it unlikely to fire for an unrelated skill.

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: 10 missing

Warning

Total

15

/

16

Passed

Repository
boisenoise/skills-collections
Reviewed

Table of Contents

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