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bun-toolkit

JS/TS/JSX toolkit with Bun awareness. Use when using Bun as a runtime, test runner, or package manager in JavaScript and TypeScript projects.

Quality

77%

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tessl review fix ./.agents/skills/bun-toolkit/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

78%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 lean, well-organized reference skill with concrete commands and specific Bun APIs that trusts the reader. Its main weaknesses are word-level marketing fluff, one non-executable snippet, and the absence of any combined workflow guidance.

Suggestions

Drop the intro sentence and evaluative adjectives ("significantly faster", "extremely fast", "high-performance") — Claude already knows Bun's performance reputation, and the facts (commands, APIs) carry the value.

Make the Bun.serve example fully executable, e.g. "Bun.serve({ port: 3000, fetch: () => new Response(\"hello\") })", so the HTTP server guidance is copy-paste ready.

Add a short note on the typical project flow (bun init → bun add → bun test → bun build) so common multi-step usage is explicit rather than implied by command order.

DimensionReasoningScore

Conciseness

The body is mostly a tight command/API reference, but the intro line "Bun is a fast, all-in-one JavaScript runtime and toolkit" and marketing adjectives ("significantly faster than `npm` or `yarn`", "extremely fast built-in web server", "high-performance" used twice) restate knowledge Claude already has and could be trimmed.

4 / 5

Actionability

Commands are concrete and largely copy-paste ready ("bun build ./index.ts --outdir ./build", "Bun.file(path)", "import { Database } from \"bun:sqlite\"") with only minor gaps such as the non-runnable ellipsis in "Bun.serve({ fetch(req) { ... } })".

4 / 5

Workflow Clarity

As a multi-task reference rather than a workflow skill, each command is unambiguous and the command list is implicitly sequenced (init, install, run, test, build); however, there is no guidance for combining steps into common project flows, and no validation checkpoints (not needed here since no destructive or batch operations are involved).

4 / 5

Progressive Disclosure

The skill is under 50 lines, needs no external references, has no bundle files (no references/, scripts/, or assets/ directories exist), contains no dangling file references, and is organized into clear sections (Core Features, Common Commands, Awareness & Best Practices, When to use) — matching the rubric's simple-skill exception for a 5.

5 / 5

Total

17

/

20

Passed

Description

65%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, well-scoped trigger clause anchored to a distinct niche (Bun), but its capability statement is generic — "toolkit with Bun awareness" says nothing about what the skill does. Converting that clause into concrete actions would lift both specificity and completeness.

Suggestions

Replace "JS/TS/JSX toolkit with Bun awareness" with concrete actions, e.g. "Run, test, install, and build JavaScript/TypeScript projects with Bun's runtime, test runner, and package manager."

Add natural trigger variations users would actually say or that appear in projects: "bun.lockb"/"bun.lock" files, and command mentions like "bun install" or "bun test".

Clarify the Bun-vs-Node boundary (e.g. "prefer over npm/node when the project uses Bun") to sharpen distinctiveness against general JS/TS tooling skills.

DimensionReasoningScore

Specificity

The capability clause "JS/TS/JSX toolkit with Bun awareness" names the domain but states no concrete actions — matching anchor 2 ("Names the domain but actions are minimal or generic") rather than 3, since no action verbs describe what the skill actually does.

2 / 5

Completeness

Both a "what" ("JS/TS/JSX toolkit with Bun awareness") and an explicit "when" ("Use when using Bun as a runtime, test runner, or package manager...") are present; the "what" is vague and the when-clause could name more concrete triggers, so anchor 4 fits better than 5 and the missing-when cap of 3 does not apply.

4 / 5

Trigger Term Quality

"Bun", "runtime", "test runner", "package manager", "JavaScript and TypeScript", and the "JS/TS/JSX" abbreviation give good natural keyword coverage, but command forms ("bun install", "bun test") and file triggers ("bun.lockb"/"bun.lock") are missing — anchor 4, not 5.

4 / 5

Distinctiveness Conflict Risk

The Bun-specific when-clause carves a clear niche with minimal conflict risk, but the broad "JS/TS/JSX toolkit" framing creates minor overlap with general JavaScript/TypeScript tooling skills — anchor 4 ("Mostly distinct; minor overlap risk") rather than 5.

4 / 5

Total

14

/

20

Passed

Validation

100%

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

saski/arnesto

Path

.agents/skills/bun-toolkit/SKILL.md

Reviewed

Table of Contents

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