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sandbox

Visual HTML canvas sandbox for agent-driven UI and live previews

58

Quality

73%

Does it follow best practices?

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SecuritybySnyk

Passed

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tessl review fix ./src/skills/bundled/sandbox/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

87%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 concise, actionable, and well-structured for a simple skill. The only notable gap is the absence of a validation/confirmation checkpoint around the destructive `/sandbox reset` operation.

Suggestions

Add a confirmation or pre-check before `/sandbox reset` (e.g. capture current state or prompt to confirm) since it destructively clears the canvas.

Note the expected server URL format or how to retrieve it after `/sandbox start` so the agent can act on the returned URL.

DimensionReasoningScore

Conciseness

The body is lean and well-organized with no padding or explanation of concepts Claude already knows; commands, an env-var table, examples, and a short "How It Works" list each earn their place, matching the score-5 "Lean and efficient" anchor.

5 / 5

Actionability

Commands are concrete and executable (`/sandbox start`, `/sandbox push <html>`, etc.) with copy-paste-ready examples covering the common cases, matching the score-5 fully-executable anchor.

5 / 5

Workflow Clarity

The "How It Works" section gives a clear 5-step sequence, but `/sandbox reset` clears all HTML/CSS/JS from the canvas, a destructive operation with no validation or confirmation step, which caps workflow clarity at 3 per the destructive-operations guideline; it is not a 2 because the sequence itself is coherent and well-ordered.

3 / 5

Progressive Disclosure

The skill is under 50 lines, single-purpose, with no bundle files and no need for external references, yet is organized into clear sections (Commands, Environment Variables, Examples, How It Works), qualifying for the score-5 simple-skill exception.

5 / 5

Total

18

/

20

Passed

Description

48%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 identifies a clear, distinct niche but is descriptive rather than action-oriented and lacks an explicit "Use when" trigger clause. Adding concrete verbs and a trigger phrase would lift the weaker dimensions.

Suggestions

Lead with concrete actions, e.g. "Pushes HTML to a live canvas for visual previews, dashboards, and agent-driven UI."

Append a trigger clause: "Use when the user wants a live HTML preview, visual dashboard, or agent-driven UI canvas."

Include natural synonyms users might say (dashboard, live preview, render) to broaden trigger coverage.

DimensionReasoningScore

Specificity

The phrase "Visual HTML canvas sandbox for agent-driven UI and live previews" names the domain clearly but uses descriptive noun phrases rather than concrete actions, matching the score-2 anchor "Names the domain but actions are minimal or generic"; it does not reach score 3 because no explicit verbs (e.g. push, render, screenshot) are listed.

2 / 5

Completeness

It gives a clear "what" (a visual HTML canvas sandbox for agent-driven UI and live previews) but has no "Use when..." trigger clause, so per the judging guidelines completeness is capped at 3; it is not a 4 because the "when" is entirely absent rather than weakly present.

3 / 5

Trigger Term Quality

Natural terms like "canvas", "live preview", and "HTML" appear, but common variations or synonyms (e.g. dashboard, preview, render) are missing, fitting the score-3 anchor of some relevant keywords without comprehensive coverage.

3 / 5

Distinctiveness Conflict Risk

"Visual HTML canvas sandbox for agent-driven UI and live previews" carves out a fairly distinct niche with low conflict risk against unrelated skills; it falls short of 5 only because trigger phrasing is not explicit enough to fully eliminate overlap with general web/preview skills.

4 / 5

Total

12

/

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.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository

alsk1992/CloddsBot

Path

src/skills/bundled/sandbox/SKILL.md

Reviewed

Table of Contents

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