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ncc

Expert guidance for @vercel/ncc — a simple CLI for compiling Node.js modules into a single file with all dependencies included. Use when bundling serverless functions, CLI tools, or any Node.js project into a self-contained file.

64

Quality

80%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./plugins/vercel/skills/ncc/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

75%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-structured reference: every command is executable and the common use cases are covered with concrete examples. Its weaknesses are redundancy — a 'Key Points' section that repeats the body and a duplicated resource link — and the absence of any output-verification or troubleshooting guidance.

Suggestions

Delete or drastically shrink the 'Key Points' section — all seven points restate content already covered in earlier sections, pure token cost.

Remove the duplicate 'Vercel Blog — ncc Introduction' entry in Official Resources, which points at the same GitHub URL as the first link.

Add a brief post-build verification step (e.g., run 'node dist/index.js' to smoke-test the bundle) to close the workflow-clarity gap.

DimensionReasoningScore

Conciseness

Mostly efficient with tables and terse commands, but the 'Key Points' section restates every earlier section, and 'Official Resources' lists a second link labeled 'Vercel Blog — ncc Introduction' that points at the identical GitHub URL.

3 / 5

Actionability

Fully executable throughout — install commands, a complete CLI flag table, and copy-paste package.json snippets covering the common cases (TypeScript, externals, serverless, CLI distribution, GitHub Actions).

5 / 5

Workflow Clarity

The core action (ncc build with flags) is unambiguous and the install → build → run sequence is clear, but there is no verification of build output or troubleshooting guidance for the multi-step patterns.

4 / 5

Progressive Disclosure

A well-organized single-file skill (Overview → Install → Usage → Options → Patterns) with no bundle files and no broken or nested references; at ~140 lines, the CLI options table and pattern cookbook could live in a reference file.

4 / 5

Total

16

/

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.

A strong description that clearly states what the tool does and when to use it, with an explicit 'Use when' clause and natural trigger terms. Its main weakness is thin capability coverage — only the core compile action is mentioned, not the secondary capabilities the body documents.

Suggestions

Add one or two secondary concrete capabilities to the description (e.g., externals for native modules, native TypeScript compilation) to lift specificity from one action to several.

Include 'ncc build' or 'single-file bundle' style phrasing to broaden trigger term coverage with the variations users actually say.

DimensionReasoningScore

Specificity

Names the domain and one concrete action ('compiling Node.js modules into a single file with all dependencies included'), but does not list several distinct capabilities such as externals, source maps, or TypeScript support.

3 / 5

Completeness

Explicitly answers both what ('a simple CLI for compiling Node.js modules into a single file with all dependencies included') and when ('Use when bundling serverless functions, CLI tools, or any Node.js project into a self-contained file') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Good natural terms — 'bundling', 'serverless functions', 'CLI tools', 'self-contained file', 'Node.js' — plus the package name, though common variations like 'ncc build' or 'single-file bundle' are missing.

4 / 5

Distinctiveness Conflict Risk

The named package and serverless/single-file triggers make it mostly distinct, though 'any Node.js project into a self-contained file' leaves minor overlap risk with generic bundler skills.

4 / 5

Total

16

/

20

Passed

Validation

87%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 14 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

metadata_field

'metadata' should map string keys to string values

Warning

Total

14

/

16

Passed

Repository

openai/plugins

Path

plugins/vercel/skills/ncc/SKILL.md

Reviewed

Table of Contents

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