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hatch-pet

Create, repair, validate, preview, and package Codex-compatible animated pet spritesheets from character art, screenshots, generated images, or visual references. Use when a user wants to hatch a Codex pet, create a custom animated pet, or build a built-in pet asset with an 8x9 atlas, transparent unused cells, row-by-row animation prompts, QA contact sheets, preview videos, and pet.json packaging. This skill composes the installed $imagegen system skill for visual generation and uses bundled scripts for deterministic spritesheet assembly.

71

Quality

89%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

77%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 an unusually well-validated workflow (deterministic QA gates, a repair feedback loop, and a precise subagent handoff contract), but it is roughly a third longer than it needs to be due to repeated restatement of the transparency and boundary rules, and it underuses its own bundled reference files by inlining their content instead of linking them. Tightening the Rules section and pointing at qa-rubric.md / codex-pet-contract.md would raise both conciseness and organization.

Suggestions

Deduplicate the transparency/effects policy: state it once in 'Transparency And Effects' and have 'Rules', the state-specific guidance, and the subagent template reference that section instead of restating it; this could cut roughly a third of the body.

Link the existing bundled references: replace the inlined geometry/QA bullets in 'Acceptance Criteria' with pointers to references/codex-pet-contract.md and references/qa-rubric.md (both currently present in the bundle but never mentioned in the body).

Move the long enumerations (pet naming examples, the allowed/forbidden effects catalog) into a reference file and keep only the decision rules in SKILL.md.

DimensionReasoningScore

Conciseness

Almost everything is novel skill-specific policy rather than concepts Claude already knows, but there is substantial repetition: the transparency/effects rules appear in 'Transparency And Effects', again as per-state guidance, again nearly verbatim in 'Rules', and again in the subagent handoff contract ('no detached effects, no wave marks for waving, no speed lines or dust for running rows'). The ~10-bullet 'Rules' section largely restates earlier sections and could be cut or compressed by roughly a third.

3 / 5

Actionability

Fully executable throughout: exact bash invocations for every script (prepare_pet_run.py, pet_job_status.py, record_imagegen_result.py, finalize_pet_run.py, queue_pet_repairs.py), expected output file trees, a copy-paste subagent handoff template, and concrete acceptance criteria. A reader can execute the whole pipeline without inventing steps.

5 / 5

Workflow Clarity

The Default Workflow is a clear numbered sequence (prepare -> inspect jobs -> generate/ingest per job -> finalize) with explicit validation checkpoints (qa/review.json, final/validation.json, contact-sheet visual review) and a genuine feedback loop: failed row QA -> queue_pet_repairs.py -> regenerate the smallest failing scope -> re-ingest. The subagent flow is an equally explicit 9-step checklist with parent/subagent write boundaries.

5 / 5

Progressive Disclosure

Section headers are clear and `references/animation-rows.md` is a real, well-signaled one-level reference, but the body inlines a lot of content that belongs in the existing bundled files: the Acceptance Criteria duplicate the geometry/QA checks already in `references/codex-pet-contract.md` and `references/qa-rubric.md`, neither of which is mentioned or linked anywhere in the body. Long inlined lists (pet naming examples, the allowed/forbidden effects catalog) would also fit better in reference files.

3 / 5

Total

16

/

20

Passed

Description

100%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.

An exemplary description: concrete verbs, explicit inputs and outputs, a clear 'Use when' clause with natural trigger phrases, and a stated composition boundary with $imagegen. It is specific, complete, and highly distinctive without padding.

DimensionReasoningScore

Specificity

The description enumerates five concrete actions ('Create, repair, validate, preview, and package Codex-compatible animated pet spritesheets') plus concrete deliverables ('8x9 atlas, transparent unused cells, row-by-row animation prompts, QA contact sheets, preview videos, and pet.json packaging'), giving comprehensive coverage of the skill's operations.

5 / 5

Completeness

It explicitly answers both questions: what ('Create, repair, validate, preview, and package Codex-compatible animated pet spritesheets from character art, screenshots, generated images, or visual references') and when ('Use when a user wants to hatch a Codex pet, create a custom animated pet, or build a built-in pet asset...') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Natural trigger phrases users would actually say are covered with synonyms and file terms: 'hatch a Codex pet', 'create a custom animated pet', 'build a built-in pet asset', plus 'spritesheets' and 'pet.json'. The body's frontmatter trigger list adds further variants, but the description itself already spans the natural vocabulary.

5 / 5

Distinctiveness Conflict Risk

It occupies a clear niche (Codex digital pet spritesheets with a fixed 8x9/192x208 atlas) with distinct triggers ('hatch a pet', 'Codex pet'); no other skill would reasonably collide, and the delegation boundary to the $imagegen system skill is stated explicitly.

5 / 5

Total

20

/

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

frontmatter_unknown_keys

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

Warning

referenced_paths_exist

Referenced path issues: 4 missing

Warning

Total

14

/

16

Passed

Repository

nexu-io/open-design

Path

skills/hatch-pet/SKILL.md

Reviewed

Table of Contents

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