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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).

91

2.21x
Quality

71%

Does it follow best practices?

Impact

93%

2.21x

Average score across 10 eval scenarios

SecuritybySnyk

Low

Low-risk findings worth noting

Fix and improve this skill with Tessl

tessl review fix ./skills/anthropic-mcp-builder/SKILL.md

The canonical home for this skill is pleaseai/mcp-dev

SKILL.md
Quality
Evals
Security

Quality

Content

63%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 body is well-structured with a clear phased workflow and reasonable conciseness, but core implementation guidance lacks inline executable code and the prominently referenced ./reference/*.md files are missing from the bundle, breaking progressive disclosure.

Suggestions

Create the referenced ./reference/ files (mcp_best_practices.md, node_mcp_server.md, python_mcp_server.md, evaluation.md) or remove/fix the broken links so navigation resolves.

Add at least one minimal, copy-paste-ready tool implementation example inline in SKILL.md so the core action is executable without depending on the missing references.

Add an explicit build/test feedback loop (e.g., 'if build fails, fix errors and re-run npm run build') in Phase 3 to reach full workflow-clarity validation.

DimensionReasoningScore

Conciseness

Mostly efficient bullets and commands with only minor over-explanation (e.g., rationale for the TypeScript choice and client-performance asides), fitting the 4 anchor better than the 3.

4 / 5

Actionability

Provides some concrete commands (npm run build, MCP Inspector, py_compile) and URLs, but the core tool-implementation guidance stays abstract ('Use Zod', 'Define outputSchema') with no executable code in the body, and the deferred code lives in reference files that do not exist.

3 / 5

Workflow Clarity

Clear four-phase sequence (Research, Implementation, Review/Test, Evaluations) with explicit verification steps (build, compile, Inspector), but lacks an explicit error-recovery feedback loop, keeping it below the 5 anchor.

4 / 5

Progressive Disclosure

Structure and signaling of the one-level-deep references are clear and well-organized, but the referenced ./reference/*.md files do not exist in the bundle, so navigation does not actually resolve — a structural gap beyond the 4 anchor's 'minor organization gaps'.

3 / 5

Total

14

/

20

Passed

Description

78%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 is specific, third-person, and explicitly answers both what the skill does and when to use it, with strong distinctiveness. The main gap is slightly less exhaustive trigger-term/when-phrase coverage than top anchors.

DimensionReasoningScore

Specificity

Names the MCP-server domain plus several concrete actions ('creating high-quality MCP servers', 'enable LLMs to interact with external services through well-designed tools', 'integrate external APIs or services'); not quite comprehensive enough for a 5 but clearly above the 3 anchor.

4 / 5

Completeness

Both 'what' (creating MCP servers enabling LLM interaction via tools) and an explicit 'when' ('Use when building MCP servers to integrate external APIs or services') are present with concrete triggers, but the when-clause is slightly less comprehensive than the 5 anchor.

4 / 5

Trigger Term Quality

Good keyword coverage including 'building MCP servers', 'external APIs or services', 'Python (FastMCP)', 'Node/TypeScript (MCP SDK)'; a few natural synonym variations and file extensions are missing, fitting the 4 anchor.

4 / 5

Distinctiveness Conflict Risk

Targets a clear niche (MCP server development) with distinct triggers (FastMCP, MCP SDK) and minimal overlap risk with unrelated skills.

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
boisenoise/skills-collections
Reviewed

Table of Contents

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