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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).

64

Quality

76%

Does it follow best practices?

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SecuritybySnyk

Low

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tessl review fix ./skills/coding-agents-and-ides/mcp-builder/SKILL.md
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.

A well-structured process guide that sequences a multi-phase workflow with verification steps and cleanly offloads detail to verified one-level-deep reference files. The main weakness is conciseness — several justifications and obvious statements could be trimmed to respect the context budget.

Suggestions

Trim explanatory padding that assumes Claude's ignorance, e.g. the TypeScript rationale ('Plus AI models are good at generating TypeScript code, benefiting from its broad usage...') and obvious restatements like 'Error messages should guide agents toward solutions'.

Make the validation feedback loop explicit in Phase 3, e.g. 'If build/inspector reports errors: fix the reported issues and re-run until clean — only proceed when validation passes,' to push workflow clarity toward 5.

Inline one small end-to-end tool example (a minimal @mcp.tool / server.registerTool snippet with a Zod/Pydantic schema) so the body is self-contained for the common case rather than deferring all executable code to the reference files.

DimensionReasoningScore

Conciseness

The body is mostly an efficient process guide, but includes unnecessary explanation/padding such as the TypeScript rationale ('Plus AI models are good at generating TypeScript code, benefiting from its broad usage...') and a few obvious statements ('Error messages should guide agents toward solutions'), so it could be tightened rather than reaching 'lean and efficient'.

3 / 5

Actionability

Concrete executable commands are present (`npm run build`, `npx @modelcontextprotocol/inspector`, `python -m py_compile your_server.py`), specific SDK features are named (Zod, `outputSchema`, `structuredContent`, annotation hints), and a copy-pasteable XML template is included; the gap is that most full code lives in reference files rather than inline.

4 / 5

Workflow Clarity

A clear four-phase sequence (Research/Planning, Implementation, Review/Test, Evaluations) with numbered subsections and a build/inspect verification checkpoint in Phase 3; it falls short of 5 because the validate→fix→retry feedback loop is not stated explicitly.

4 / 5

Progressive Disclosure

SKILL.md acts as a clear overview pointing to well-signaled, one-level-deep references (mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) and scripts, all of which exist in the bundle; navigation is easy and content is appropriately split.

5 / 5

Total

16

/

20

Passed

Description

82%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.

A strong description that clearly states both what the skill does and when to use it, with a distinct MCP-specific niche and good natural trigger terms. Its only weakness is moderate specificity — it frames the activity in a few ways rather than enumerating multiple distinct concrete operations.

DimensionReasoningScore

Specificity

Names the MCP-server domain with a couple of concrete framings ('creating high-quality MCP servers', 'integrate external APIs or services') but does not list multiple distinct concrete operations like the score-5 anchor; it stays at 'domain + 1-2 actions, not comprehensive'.

3 / 5

Completeness

Explicitly answers '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, matching the score-5 anchor.

5 / 5

Trigger Term Quality

Natural keywords users would say are present ('MCP servers', 'external APIs', 'Python (FastMCP)', 'Node/TypeScript', 'MCP SDK'), giving good coverage; a few natural variations/synonyms (e.g. 'MCP' alone, 'tool integration') are missing, so it does not reach 5.

4 / 5

Distinctiveness Conflict Risk

'MCP (Model Context Protocol) servers' is a clear, narrow niche with distinct triggers and minimal overlap risk with other skills.

5 / 5

Total

17

/

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: 1 missing

Warning

Total

15

/

16

Passed

Repository
eigent-ai/agent-skills
Reviewed

Table of Contents

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