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mcp-builder-ms

Use this skill when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).

Quality

69%

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SecuritybySnyk

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tessl review fix ./plugins/AI-Agents-Safe-Coding-Skills/skills/mcp-builder-ms/SKILL.md

The canonical home for this skill is mcp-builder-ms in administrakt0r/AI-Agents-Safe-Coding-Skills

SKILL.md
Quality
Evals
Security

Quality

Content

56%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 has a well-sequenced four-phase workflow with real commands and validation checkpoints, and its structure as an overview delegating detail to guides is the right pattern. However, the referenced guides are name-only pointers to files that are missing from the bundle, the implementation guidance lacks any executable code, and the guide listings are repeated across three sections.

Suggestions

Resolve the dangling references: replace emoji-name pointers ('⚡ TypeScript Guide', '✅ Evaluation Guide', '🔷 Microsoft MCP Patterns', '📋 MCP Best Practices') with actual paths (e.g., [TypeScript Guide](references/typescript.md)) and ship those files in references/, so progressive disclosure actually works.

Add one minimal executable tool-registration example inline (FastMCP `@mcp.tool` and TypeScript `server.registerTool`) so the implementation phase is actionable even before loading the guides.

De-duplicate the guide listings repeated in Phase 1.3, Phase 2.1, and the Reference Files section into a single consolidated pointer list, and add an explicit feedback loop in Phase 3 ('if build/inspector checks fail, fix and re-run until they pass').

DimensionReasoningScore

Conciseness

Tables are token-efficient, but the body includes noticeable padding: the Microsoft MCP ecosystem catalog ('Azure MCP | 48+ Azure services...'), the same guide pointers listed three times (Phase 1.3, Phase 2.1, and the Reference Files section), and bullets re-explaining basics Claude already knows ('No duplicated code (DRY principle)', 'Async/await for I/O operations'). Mostly efficient but could be tightened — anchor 3, not 4, because the duplication and known-concept explanations are more than minor.

3 / 5

Actionability

There are concrete commands ('npx @modelcontextprotocol/inspector', 'npm run build', 'python -m py_compile your_server.py', the sitemap URL, and the evaluation XML example), but the core 'Implement Tools' section is abstract bullet direction ('Create shared utilities: API client with authentication', 'Use Zod (TypeScript) or Pydantic (Python)') with no executable code, and the guides holding the actual examples are not present in the bundle — matching anchor 3 ('some concrete guidance but incomplete... missing key details') rather than anchor 4's mostly-executable guidance.

3 / 5

Workflow Clarity

The four phases (Deep Research and Planning → Implementation → Review and Test → Create Evaluations) are clearly sequenced with numbered subsections, and Phase 3 provides verification checkpoints ('Run npm run build to verify compilation', 'Test with MCP Inspector'). It falls short of anchor 5 because there is no explicit fix-and-retry feedback loop after validation (e.g., 'if the build fails, fix errors and rebuild'), but no destructive/batch cap applies.

4 / 5

Progressive Disclosure

The overview-pointing-to-guides design is right, but the references are emoji-labeled names with no file paths ('⚡ TypeScript Guide', '🔷 Microsoft MCP Patterns', '✅ Evaluation Guide', '📋 MCP Best Practices'), and none of the referenced files exist in the bundle (no references/ directory at all), so navigation is impossible in practice — matching anchor 3 ('references present but not clearly signaled') rather than anchor 4's mostly-clear references.

3 / 5

Total

13

/

20

Passed

Description

70%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 has an explicit and well-formed 'Use when' trigger with good natural keywords (MCP servers, FastMCP, Node/TypeScript) and a clear niche. Its main weakness is that the 'what' side is thin — it names the single action of building MCP servers without enumerating the concrete capabilities the skill provides.

Suggestions

Enumerate concrete capabilities before the trigger clause, e.g., 'Design, implement, test, and evaluate MCP servers that integrate external APIs or services — tool schemas, error handling, and evaluation suites — in Python (FastMCP) or Node/TypeScript (MCP SDK).'

Add the spelled-out protocol name ('Model Context Protocol', 'Model Context Protocol server') so users who say the full name instead of 'MCP' still trigger the skill.

Sharpen distinctiveness by scoping the trigger, e.g., 'Use when the user wants to build or expose an MCP/Model Context Protocol server', to reduce overlap with generic API-integration requests.

DimensionReasoningScore

Specificity

Quotes: 'building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK)' — names the domain and one concrete action with language stacks, but does not list several specific actions (tool design, implementation, testing, evaluations) that anchor 4/5 examples enumerate.

3 / 5

Completeness

Quotes: 'Use this skill when building MCP servers to integrate external APIs or services' — an explicit 'when' clause is present and the 'what' (building MCP servers) is clear, but the 'what' is thin and merged with the trigger rather than enumerating concrete capabilities, falling short of anchor 5's 'clearly and explicitly answers both what AND when with concrete trigger phrases'.

4 / 5

Trigger Term Quality

Quotes: 'MCP servers', 'external APIs or services', 'Python (FastMCP)', 'Node/TypeScript (MCP SDK)' — good natural keyword coverage users would say when needing this skill, though 'Model Context Protocol' spelled out and 'integrations' are missing, so not the comprehensive synonym coverage of anchor 5.

4 / 5

Distinctiveness Conflict Risk

Quotes: 'building MCP servers to integrate external APIs or services' — the MCP-server-building niche is mostly distinct, but the 'integrate external APIs or services' portion carries minor overlap risk with generic API-integration skills, matching anchor 4 ('mostly distinct; minor overlap risk with closely related skills') rather than anchor 5's minimal conflict risk.

4 / 5

Total

15

/

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.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository

administrakt0r/AI-Agents-Safe-Coding-Skills

Path

plugins/AI-Agents-Safe-Coding-Skills/skills/mcp-builder-ms/SKILL.md

Reviewed

Table of Contents

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