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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

71%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

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tessl review fix ./.agents/skills/mcp-builder/SKILL.md
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 content is a well-sequenced process guide with concrete build/test commands, but it leans on reference files that are absent from the bundle and duplicates its reference links in a Documentation Library section. Tightening the duplication and wiring up the existing scripts/ harness would lift it notably.

Suggestions

Remove the duplicated 'Reference Files' library section or consolidate it with the inline Phase 1/4 links to cut roughly 45 lines of repetition.

Ship the four ./reference/*.md files the body links to (mcp_best_practices, node_mcp_server, python_mcp_server, evaluation) so the delegated implementation guidance is actually reachable.

Link the existing scripts/ evaluation harness (connections.py, evaluation.py, example_evaluation.xml) from Phase 4, and add an explicit 'if build/Inspector test fails → fix → re-run' feedback loop to Phase 3.

DimensionReasoningScore

Conciseness

The body largely avoids explaining basics Claude already knows, but the 'Reference Files' section (lines 211-256) duplicates the inline links already given in Phase 1 and Phase 4 (best practices, Python/TypeScript guides, evaluation guide each appear twice), so it could be tightened noticeably.

3 / 5

Actionability

Some concrete executable commands appear ('npm run build', 'npx @modelcontextprotocol/inspector', 'python -m py_compile', WebFetch URLs), but the core implementation guidance (actual tool code, schema patterns) is delegated to ./reference/*.md files that are not present, leaving key details missing.

3 / 5

Workflow Clarity

A clear four-phase sequence (Research → Implementation → Review/Test → Evaluations) with build and MCP-Inspector test checkpoints in Phase 3; minor gap is the absence of an explicit 'if build/test fails → fix → retry' feedback loop in the body itself.

4 / 5

Progressive Disclosure

In-body structure is well-signaled with labeled one-level-deep links, but scored against the actual bundle all four ./reference/*.md targets are missing while the real scripts/ bundle (the evaluation harness for Phase 4) is never linked, so the disclosure is partly broken.

3 / 5

Total

13

/

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.

The description is strong: third-person, explicit 'Use when' trigger, and a well-scoped niche with concrete framework callouts. It is comprehensive on completeness and distinctiveness, with only minor granularity gaps in specificity and a few missing trigger synonyms.

DimensionReasoningScore

Specificity

Lists several concrete actions — 'creating high-quality MCP servers', 'enable LLMs to interact with external services', 'building MCP servers', 'integrate external APIs or services' — but actions stay at the server/domain level rather than enumerating fine-grained operations, leaving minor coverage gaps.

4 / 5

Completeness

Explicitly answers both what ('Guide for creating high-quality MCP servers that enable LLMs to interact with external services through well-designed tools') and when ('Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK)') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Good natural keyword coverage with synonyms — 'MCP servers', 'Model Context Protocol', 'external APIs or services', 'Python (FastMCP)', 'Node/TypeScript (MCP SDK)' — that a user would say; a few variations (e.g. 'MCP server' singular, 'model context protocol server') are absent, keeping it just short of comprehensive.

4 / 5

Distinctiveness Conflict Risk

Occupies a clear niche (MCP server authoring) with highly specific triggers — 'Model Context Protocol', 'FastMCP', 'MCP SDK' — that are unlikely to fire for unrelated skills, giving minimal conflict risk.

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: 10 missing

Warning

Total

15

/

16

Passed

Repository
openstatusHQ/data-table-filters
Reviewed

Table of Contents

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