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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

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

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 guide has a clear four-phase structure and useful concrete commands, but it suffers from conceptual padding, no in-body executable tool code, missing validate→fix→retry feedback loops, and — most critically — references to a ./reference/ directory that is absent from the actual bundle.

Suggestions

Create the missing ./reference/ directory (mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) or fix the link paths to point at files that actually exist in the bundle.

Trim the conceptual tradeoff prose in §1.1 (e.g. the workflow-tools-vs-API-coverage paragraph) to leaner directive guidance.

Add an explicit validate→fix→retry feedback loop in Phase 3 (e.g. 'If build or inspector fails: read the error, fix, re-run; only proceed when checks pass') and include at least one complete executable tool example in-body or clearly linked.

DimensionReasoningScore

Conciseness

Largely structured as tight bullets and sections, but §1.1 pads with conceptual tradeoff prose ('Performance varies by client—some clients benefit from code execution that combines basic tools, while others work better with higher-level workflows') that could be trimmed; not a 3 because not every token earns its place.

2 / 3

Actionability

Provides some concrete commands ('npm run build', 'npx @modelcontextprotocol/inspector', 'python -m py_compile'), real URLs, and an XML template, but offers no complete executable tool-implementation code in-body — that is deferred to reference files — so it lands at 'some concrete guidance but incomplete' rather than copy-paste ready.

2 / 3

Workflow Clarity

Four phases are clearly sequenced and Phase 3 includes build/test verification, but there is no explicit validate→fix→retry feedback loop and checkpoints are largely implicit, matching the 'steps listed but validation gaps' anchor.

2 / 3

Progressive Disclosure

References are well-signaled and conceptually one level deep, but the body repeatedly links to ./reference/mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, and evaluation.md — a ./reference/ directory that does not exist in the bundle (only ./scripts/ exists). Scored against the actual bundle structure, the dead links and inline-heavy overview keep this below 3.

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 an explicit 'Use when' trigger, good natural-language trigger coverage, and a distinct niche. The only weakness is that the action verbs are somewhat generic rather than enumerating concrete capabilities.

DimensionReasoningScore

Specificity

Names the domain and several actions ('creating high-quality MCP servers', 'building MCP servers to integrate external APIs or services'), but the verbs are generic (create/build/integrate) rather than distinct concrete capabilities, falling short of the multi-action 3 anchor.

2 / 3

Completeness

Explicitly answers what ('Guide for creating high-quality MCP servers that enable LLMs to interact with external services') and when via an explicit 'Use when building MCP servers...' trigger clause.

3 / 3

Trigger Term Quality

Covers natural terms a developer would say — 'building MCP servers', 'integrate external APIs or services', plus language variants 'Python (FastMCP)' and 'Node/TypeScript (MCP SDK)'.

3 / 3

Distinctiveness Conflict Risk

MCP server authoring is a clear niche with distinct triggers unlikely to collide with other skills.

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
databricks/devhub
Reviewed

Table of Contents

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