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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).

60

Quality

70%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

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tessl review fix ./mcp-builder/skills/mcp-builder/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

50%

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

A well-organized, sequenced MCP-building guide with genuinely useful specifics (documentation URLs, tool annotations), but it lacks executable code, repeats generic programming principles, and omits explicit validation feedback loops. Progressive disclosure is unused despite the body's length.

Suggestions

Replace generic programming advice (DRY, type safety, full documentation) with MCP-specific guidance or remove it, since Claude already knows these concepts.

Add a minimal executable tool-registration example (Pydantic/Zod schema + handler) so the implementation guidance is copy-paste ready rather than descriptive.

Insert an explicit validate->fix->retry checkpoint in Phase 3 (e.g., run evaluations, fix failures, re-run until passing) before proceeding, and consider splitting detailed patterns into a referenced file.

DimensionReasoningScore

Conciseness

The bullet-point format avoids verbose prose, but it spends tokens restating concepts Claude already knows ("DRY Principle: No duplicated code", "Type Safety: Full type coverage", "Documentation: Every tool has comprehensive docstrings").

2 / 3

Actionability

It offers some concrete specifics (WebFetch URLs for MCP/SDK docs, exact tool-annotation hints like readOnlyHint/destructiveHint), but provides no executable code for tool registration or schema definition, describing rather than instructing in most sections.

2 / 3

Workflow Clarity

The four phases (Research, Implementation, Review, Evaluations) are clearly sequenced, but Phase 3 is a review checklist with no explicit validate->fix->retry feedback loop or "only proceed when X passes" checkpoint, capping it per the rubric's feedback-loop guidance.

2 / 3

Progressive Disclosure

No bundle files exist (references/scripts/assets absent) and all content sits inline in a ~120-line SKILL.md; it is well-sectioned but detailed material like implementation patterns and evaluation criteria that could live in separate files is not split out.

2 / 3

Total

8

/

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 with a clear niche, explicit third-person trigger guidance, and good natural keyword coverage. It is held back only by mildly abstract capability phrasing ("well-designed tools", "high-quality") instead of enumerating concrete actions.

DimensionReasoningScore

Specificity

It names the domain and actions ("creating high-quality MCP servers", "integrate external APIs or services") but relies on abstract phrasing like "well-designed tools" rather than listing multiple concrete, distinct actions as the top anchor requires.

2 / 3

Completeness

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

3 / 3

Trigger Term Quality

The "Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK)" clause covers natural terms a developer would actually say, including SDK variants.

3 / 3

Distinctiveness Conflict Risk

The MCP-server niche with Python/Node variants and integration triggers is distinct and unlikely to fire for unrelated skills.

3 / 3

Total

11

/

12

Passed

Validation

100%

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

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
composio-community/awesome-claude-plugins
Reviewed

Table of Contents

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