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mcp-builder

Build MCP servers in Python with FastMCP. Define tools / resources / prompts, build the server, test locally, deploy to FastMCP Cloud or Docker. Use whenever the user mentions building an MCP server, exposing tools to LLMs, FastMCP, building a Claude integration, or troubleshooting FastMCP module-level server, storage, lifespan, middleware, OAuth, or deployment errors.

Quality

90%

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SKILL.md
Quality
Evals
Security

Quality

Content

88%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 highly actionable, well-sequenced skill: executable guidance throughout, an explicit validation checklist before deploy, and clearly signaled one-level-deep references. The remaining gaps are minor duplication of server scaffold patterns inline and incomplete navigation to the provided bundle files.

Suggestions

Document the unreferenced bundle files in the Asset Files section: assets/api-client-pattern.py, assets/error-handling.py, assets/openapi-integration.py, assets/pyproject.toml, and assets/requirements.txt exist in the bundle but appear nowhere in SKILL.md, making them undiscoverable.

Consolidate the repeated server scaffold examples (Step 2, Cloud-Ready Server Pattern, Self-Contained Server) into one canonical pattern and point to assets/self-contained-server.py for the full version, trimming roughly 40 lines of duplication.

DimensionReasoningScore

Conciseness

The body is dense with executable code and commands and never explains concepts Claude already knows, but the module-level-server rule and near-identical server scaffolds repeat across Step 2, Critical Patterns, and Production Patterns, giving more than the 'lean, every token earns its place' ideal.

4 / 5

Actionability

Everything is copy-paste ready: pip install, complete server code, a runnable FastMCP Client test script, py_compile/grep validation one-liners, a Dockerfile, and a CLI quick reference, covering the common cases end to end.

5 / 5

Workflow Clarity

The six-step workflow (define, scaffold, scripts, test, checklist, deploy) includes an explicit required-vs-advisory pre-deploy checklist with the rule "All required checks must pass", plus an error-to-fix table that provides feedback loops for error recovery.

5 / 5

Progressive Disclosure

Structure is good: references/integration-patterns.md is one level deep and clearly signaled with a summary of its contents, and the Asset Files section lists most bundle files with descriptions, all of which exist. However, 5 of 13 bundle files (api-client-pattern.py, error-handling.py, openapi-integration.py, pyproject.toml, requirements.txt) are referenced nowhere in SKILL.md, and the advanced Production/Context sections duplicate content already in assets.

4 / 5

Total

18

/

20

Passed

Description

88%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: it states concrete capabilities across the full lifecycle and has an explicit, richly populated 'Use when...' trigger clause including error-troubleshooting terms. Its only weaknesses are a few missing natural synonyms and slightly broad integration triggers that pose minor conflict risk.

DimensionReasoningScore

Specificity

"Define tools / resources / prompts, build the server, test locally, deploy to FastMCP Cloud or Docker" lists multiple concrete actions covering the full build-to-deploy lifecycle, matching the comprehensive-coverage anchor rather than the 'minor gaps' level below it.

5 / 5

Completeness

It explicitly answers both 'what' (build, test, and deploy Python MCP servers with FastMCP, defining tools/resources/prompts) and 'when' via an explicit "Use whenever the user mentions..." clause with concrete trigger phrases, matching the top anchor exactly.

5 / 5

Trigger Term Quality

Natural phrases like "building an MCP server", "FastMCP", "building a Claude integration", and troubleshooting triggers ("module-level server, storage, lifespan, middleware, OAuth, or deployment errors") give good coverage, but common synonyms such as "Model Context Protocol" spelled out are missing, so it falls just short of the comprehensive-synonyms anchor.

4 / 5

Distinctiveness Conflict Risk

The FastMCP/Python MCP-server niche is unmistakable, but the trigger phrases "building a Claude integration" and "exposing tools to LLMs" are broad enough to create minor overlap with closely related Claude-development skills, fitting the 'minor overlap risk' anchor rather than minimal conflict risk.

4 / 5

Total

18

/

20

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.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

jezweb/claude-skills

Path

plugins/integrations/skills/mcp-builder/SKILL.md

Reviewed

Table of Contents

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