bun-runtime

Bun as runtime, package manager, bundler, and test runner. When to choose Bun vs Node, migration notes, and Vercel support.

Quality

75%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/bun-runtime/SKILL.md

Quality

Content

76%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 highly actionable with copy-paste-ready commands and well-organized sections, but the migration workflow lacks validation checkpoints and minor verbosity plus an inline API reference keep conciseness and progressive disclosure just below full marks.

Suggestions

Add a validation/feedback step to the Node-to-Bun migration workflow (e.g. run `bun test` after migrating and fix any Bun-incompatible packages before proceeding) to raise workflow clarity.

Trim low-value context like 'built on JavaScriptCore, implemented in Zig' and 'Bun and the ecosystem evolve quickly' to improve token efficiency.

Consider moving the Runtime API examples (Bun.file, Bun.serve) into a separate REFERENCE.md so the overview stays lean and under the 50-line simple-skill threshold.

Dimension	Reasoning	Score
Conciseness	Mostly lean bullets and code with no padding about basic concepts, but minor over-explanation ('built on JavaScriptCore, implemented in Zig', 'Bun and the ecosystem evolve quickly') keeps it just below the fully-lean anchor.	4 / 5
Actionability	Copy-paste-ready commands and code cover the common cases — install, run, env, test (with bun:test), Runtime API (Bun.file/Bun.serve), and Vercel build steps with --frozen-lockfile.	5 / 5
Workflow Clarity	The 'Migration from Node' guidance is a loose multi-step sequence (replace node with bun run, run bun install, use bun run for scripts) but lacks validation checkpoints or feedback loops, matching the anchor with validation gaps.	3 / 5
Progressive Disclosure	Well-organized sections (When to Use, How It Works, Examples, Best Practices) with no nested references, though the inline Runtime API examples could be split into a separate reference file since the body exceeds 50 lines.	4 / 5
	Total	16 / 20 Passed

Description

75%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 and clearly distinguishable, naming concrete Bun capabilities and natural trigger terms, but it omits an explicit 'Use when...' clause, which caps completeness at 3.

Suggestions

Add an explicit 'Use when...' clause with concrete trigger phrases, e.g. 'Use when adopting Bun, migrating Node scripts to Bun, or configuring the Bun runtime on Vercel.'

Broaden trigger-term coverage with synonyms and CLI/file extensions like 'bun.lock', 'bun test', and '.ts' that users actually mention.

Convert 'When to choose Bun vs Node' from a topic label into an explicit when-to-use statement to lift completeness above 3.

Dimension	Reasoning	Score
Specificity	Names four concrete toolchain roles ('runtime, package manager, bundler, and test runner') plus distinct capabilities ('When to choose Bun vs Node', 'migration notes', 'Vercel support'), matching the comprehensive-coverage anchor.	5 / 5
Completeness	Has a clear 'what' but lacks an explicit 'Use when...' trigger clause; 'When to choose Bun vs Node' reads as a topic covered rather than explicit when-to-use guidance, so completeness is capped at 3 per the rubric guideline.	3 / 5
Trigger Term Quality	Includes natural terms a user would say ('Bun', 'Node', 'Vercel', 'migration') but omits common synonyms and file/CLI extensions like 'bun.lock', 'bun test', or '.ts' that anchor 5 expects.	4 / 5
Distinctiveness Conflict Risk	'Bun' is a clear niche with distinct triggers (Bun, Vercel runtime, migration from Node) and minimal overlap risk with other skills.	5 / 5
	Total	17 / 20 Passed

Validation

87%

Warnings & errors only

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

Criteria	Description	Result
metadata_version	'metadata.version' is missing	Warning
referenced_paths_exist	Referenced path issues: 1 missing	Warning

	Total	14 / 16 Passed

Repository: affaan-m/ECC
Path: skills/bun-runtime/SKILL.md
Commit: d8409a4

Reviewed: 1 day ago

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