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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

71%

Does it follow best practices?

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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

60%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.

The skill body presents a clear four-phase workflow with concrete commands and well-signaled progressive disclosure, but it is hurt by repeated documentation references, rationale Claude already knows, and most critically by inline references to ./reference/*.md files that are not shipped with the bundle.

Suggestions

Ship the referenced bundle files (./reference/mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) or inline the essential parts so the skill is self-contained.

Remove duplicated documentation listings — the SDK READMEs and language guides appear in both Phase 1.3 and the Reference Files section; consolidate to one location.

Trim explanatory rationale Claude already knows (e.g., why TypeScript is recommended, what AI models are good at) to improve token efficiency.

DimensionReasoningScore

Conciseness

The body is mostly efficient but includes unnecessary rationale ('AI models are good at generating TypeScript code, benefiting from its broad usage, static typing and good linting tools') and repeats the SDK/language-guide references twice (Phase 1.3 and the Reference Files section), fitting 'mostly efficient but includes some unnecessary explanation or could be tightened'.

3 / 5

Actionability

There are concrete commands and URLs (sitemap, raw GitHub READMEs, 'npm run build', 'npx @modelcontextprotocol/inspector', 'python -m py_compile', an XML example), but the actual tool-implementation code is delegated to ./reference/*.md files that are not present, leaving key details missing — matching 'some concrete guidance but incomplete; missing key details'.

3 / 5

Workflow Clarity

Four phases are clearly sequenced (Research/Planning, Implementation, Review/Test, Create Evaluations) with checkpoints like 'npm run build to verify compilation', MCP Inspector, py_compile, and a code-quality review, fitting 'clear sequence with most checkpoints present; minor validation gaps'.

4 / 5

Progressive Disclosure

The body is structured as an overview with well-signaled, one-level-deep references organized by phase ('Load During Phase 1/2', etc.), but the referenced bundle files (./reference/mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) do not exist in the skill bundle, a minor organization gap that fits 'good structure; most content appropriately placed; references mostly clear; minor organization gaps'.

4 / 5

Total

14

/

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.

The description cleanly answers both what the skill does and when to use it, with a distinct, low-conflict niche around MCP server building. Its main weakness is specificity: it describes building/integrating at a high level rather than enumerating multiple concrete operations.

DimensionReasoningScore

Specificity

The description names the domain ('creating high-quality MCP servers', 'enable LLMs to interact with external services through well-designed tools', 'integrate external APIs or services') but stays at the level of building/integrating rather than listing multiple discrete concrete actions, matching 'names domain and 1-2 concrete actions, but not comprehensive'.

3 / 5

Completeness

It explicitly states 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, whether in Python ... or Node/TypeScript ...') with concrete trigger phrases, matching the top anchor.

5 / 5

Trigger Term Quality

Natural trigger phrases are present ('Use when building MCP servers to integrate external APIs or services', 'Python (FastMCP)', 'Node/TypeScript (MCP SDK)') giving good keyword coverage, though a few common variations a user might say are missing, fitting 'good keyword coverage; a few natural terms missing'.

4 / 5

Distinctiveness Conflict Risk

'Model Context Protocol' server building is a clear niche with distinct triggers and minimal conflict risk with other skills, matching 'clear niche with distinct triggers; minimal conflict risk'.

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: 10 missing

Warning

Total

15

/

16

Passed

Repository
pskoett/pskoett-ai-skills
Reviewed

Table of Contents

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