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build-mcp

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).

64

Quality

77%

Does it follow best practices?

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SecuritybySnyk

Low

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tessl review fix ./antigravity/skills/build-mcp/SKILL.md

The canonical home for this skill is build-mcp in NeoLabHQ/context-engineering-kit

SKILL.md
Quality
Evals
Security

Quality

Content

67%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 well-structured, actionable four-phase guide with concrete commands and a clear progressive-disclosure design. Its main weaknesses are redundancy from restating the references and description multiple times, implicit rather than explicit error-recovery loops, and — most importantly — all four ./reference/ files it points to are missing from the bundle.

Suggestions

Ship the missing bundle files (reference/mcp_best_practices.md, python_mcp_server.md, node_mcp_server.md, evaluation.md) or remove the broken links — every inline reference currently resolves to nothing.

De-duplicate the reference listings: keep a single Documentation Library section and have the phase steps point to it, instead of re-listing the same four links in Phase 1.4, Phase 2.4, and the trailing section.

Add an explicit validate->fix->retry feedback loop in Phase 3.2 (e.g. 'If `npm run build` fails, fix the reported errors and re-run until it succeeds') to lift workflow clarity.

DimensionReasoningScore

Conciseness

Largely directive and useful rather than explaining basics Claude already knows, but the Overview restates the frontmatter description and the reference files are listed three times (inline in Phase 1.4, again in Phase 2.4, and again in the trailing Reference Files section), which is the 'mostly efficient but could be tightened' anchor rather than lean.

3 / 5

Actionability

Provides concrete, executable guidance — exact WebFetch URLs, commands like `timeout 5s python server.py`, `python -m py_compile`, `npm run build`, specific tool annotations (readOnlyHint etc.) and a full XML evaluation example — with the only gap being that complete code samples are delegated to the reference files, fitting the 'mostly executable; minor gaps' anchor.

4 / 5

Workflow Clarity

Four clearly sequenced phases with numbered subsections and validation checkpoints (py_compile, build verification, quality checklist, the hang-warning), but error-recovery feedback loops (validate -> fix -> retry) are only implied rather than explicit, which matches 'clear sequence with most checkpoints; minor validation gaps' rather than the explicit-loop 5.

4 / 5

Progressive Disclosure

Good structure with clearly signaled, one-level-deep references and an organized Documentation Library section, but the four referenced files under ./reference/ do not exist in the bundle, so the advertised split content is not actually delivered — a real organization gap that keeps it below the clear-overview 5.

4 / 5

Total

15

/

20

Passed

Description

87%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, well-formed description: explicit what and when, distinct MCP niche, and good natural trigger terms with language variants. The only gap is that the action list is solid rather than comprehensively enumerated, which caps specificity and trigger coverage at 4.

DimensionReasoningScore

Specificity

Names the domain ('MCP servers') and several concrete actions ('creating', 'building', 'integrate external APIs or services') plus language variants, but stops short of a comprehensive multi-action list, fitting the 'several specific actions; minor gaps' anchor rather than the exhaustive 5.

4 / 5

Completeness

Clearly answers 'what' ('Guide for creating high-quality MCP servers that enable LLMs to interact with external services through well-designed tools') and 'when' with an explicit 'Use when building MCP servers...' trigger clause, matching the both-what-and-when-with-concrete-triggers anchor.

5 / 5

Trigger Term Quality

Strong natural keywords a user would actually say ('building MCP servers', 'integrate external APIs or services', 'Python (FastMCP)', 'Node/TypeScript (MCP SDK)') with good coverage, but a few synonyms (e.g. 'tool server', '.mcp') are absent, so it is not the comprehensive 5.

4 / 5

Distinctiveness Conflict Risk

'build-mcp' / 'building MCP servers' is a clear niche with distinct triggers and minimal overlap with other skills, matching the clear-niche anchor; voice is appropriately third person/imperative so no penalty applies.

5 / 5

Total

18

/

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: 14 missing

Warning

Total

15

/

16

Passed

Repository
NeoLabHQ/context-engineering-kit
Reviewed

Table of Contents

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