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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).

63

Quality

75%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Low

Low-risk findings worth noting

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tessl review fix ./.agents/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.

The body is well-organized into a clear four-phase workflow with concrete build/test commands, but it leans on explanatory prose Claude already knows and delegates core executable guidance to references that are not present in the bundle.

Suggestions

Add at least one minimal executable tool-implementation code snippet (Zod/Pydantic input schema + tool registration) directly in the body so the core guidance is actionable without the referenced files.

Tighten or remove concept-restating prose (tool-naming rationale, async/await, error-message basics) and drop the Overview that repeats the frontmatter description verbatim.

Fix the broken references by either creating the ./reference/ directory with the cited files or correcting the paths (e.g., pointing to scripts/ where the evaluation script actually lives).

DimensionReasoningScore

Conciseness

Mostly efficient and well-sectioned, but includes prose Claude already knows (e.g., "Clear, descriptive tool names help agents find the right tools quickly", the Overview echoing the description, restating async/await and error-message basics) that could be tightened.

2 / 3

Actionability

Concrete commands exist (npm run build, MCP Inspector, py_compile, WebFetch URLs, annotation hints), but the core tool-implementation guidance is descriptive ("Use Zod or Pydantic", "Define outputSchema") with no executable code example in the body — the real detail is offloaded to references.

2 / 3

Workflow Clarity

A clear four-phase sequence with a build/test verification step in Phase 3, but it lacks explicit validate→fix→retry feedback loops and checklists, and testing defers to "see language-specific guides".

2 / 3

Progressive Disclosure

References are clearly signaled and organized with a navigation section, but every local link points to ./reference/*.md and that directory does not exist in the bundle (only scripts/ is present), so the one-level-deep references are broken against the actual bundle structure.

2 / 3

Total

8

/

12

Passed

Description

100%

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, uses natural third-person trigger terms, and clearly answers both what and when, with a distinct niche that minimizes conflict risk.

DimensionReasoningScore

Specificity

Lists multiple concrete actions — "creating high-quality MCP servers", "interact with external services through well-designed tools", "integrate external APIs or services" — matching the anchor for listing several specific concrete actions.

3 / 3

Completeness

Explicitly answers both what ("Guide for creating high-quality MCP servers that enable LLMs to interact with external services through well-designed tools") and when ("Use when building MCP servers to integrate external APIs or services").

3 / 3

Trigger Term Quality

Natural trigger terms a user would say appear directly — "MCP servers", "external APIs", "integrate ... services", "Python (FastMCP)", "Node/TypeScript (MCP SDK)" — giving good coverage rather than technical jargon.

3 / 3

Distinctiveness Conflict Risk

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

3 / 3

Total

12

/

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
openstatusHQ/data-table-filters
Reviewed

Table of Contents

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