decompose-into-slices

Break a plan or milestone brief into independently-grabbable vertical slices (tracer bullets). Produces slices in `M###-ROADMAP.md` by default, or GitHub issues only with explicit user confirmation. Use when asked to "break this into slices", "decompose the plan", "vertical slices", "break into issues", or when a plan is ready but needs task-level decomposition. Prefers many thin slices over few thick ones; marks dependency order explicitly.

Quality

96%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

92%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is an exceptionally clear, actionable, well-gated workflow that assumes Claude's competence and avoids concept-explanation fluff. Its only weakness is progressive disclosure: it is a long single file with sizable inline templates that could live in reference files.

Suggestions

Move the full GitHub issue-body template (the ~20-line block in Step 6) into a reference file such as references/issue-template.md and link to it, keeping only a one-line summary inline.

Extract the roadmap template field list (Vision, Success Criteria, Key Risks, Proof Strategy, Verification Classes, Definition of Done, Requirement Coverage, Horizontal Checklist, Boundary Map) into references/roadmap-fields.md so SKILL.md stays an overview pointing to detail.

If the external repo template at src/resources/extensions/gsd/templates/roadmap.md is the canonical slice format, reference it earlier and more prominently (Step 1 already does) rather than re-stating the format block inline in Step 5.

Dimension	Reasoning	Score
Conciseness	Lean and purposeful — it does not explain concepts Claude already knows and every section (core_principle, anti_patterns, success_criteria as checklists) earns its place; the vertical/horizontal framing is GSD-specific discipline, not generic padding, matching the score-3 anchor.	3 / 3
Actionability	Provides copy-paste-ready formats — the exact roadmap markdown block, the full GitHub issue body template, specific tool calls (mcp__github__issue_read, mcp__github__issue_write) and a concrete write path — matching the score-3 anchor of fully executable, specific examples.	3 / 3
Workflow Clarity	A clear 6-step sequence with explicit validation gates ('Do not proceed to Step 5 without explicit approval', 'Iterate on feedback until the user approves') and a confirmation gate on the destructive outward action (GitHub issue filing), matching the score-3 anchor with feedback loops and checkpoints.	3 / 3
Progressive Disclosure	Sections are well-organized (objective/context/core_principle/process/anti_patterns/success_criteria) and it points to an external template for the exact slice format, but the full issue-body template and roadmap-field enumeration are inline with no bundle files to offload them, matching the score-2 anchor of good structure with inline content that could be separate; not a 3 because the skill exceeds 50 lines and is effectively monolithic.	2 / 3
	Total	11 / 12 Passed

Description

100%

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 third-person, concrete, and pairs explicit trigger phrases with a clear statement of both what the skill does and when to use it. It is one of the strongest possible descriptions against this rubric.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — 'Break a plan or milestone brief into independently-grabbable vertical slices', 'Produces slices in M###-ROADMAP.md by default, or GitHub issues only with explicit user confirmation', 'marks dependency order explicitly' — matching the score-3 anchor of several specific concrete actions.	3 / 3
Completeness	Explicitly answers both what (decompose into slices, produce roadmap/issues) and when via a 'Use when...' clause with explicit triggers, matching the score-3 anchor; not a 2 because the when is explicit rather than implied.	3 / 3
Trigger Term Quality	Quotes natural phrasings users would actually say — "break this into slices", "decompose the plan", "vertical slices", "break into issues" — giving good coverage of common variations, matching the score-3 anchor; not below because it is not missing common variations.	3 / 3
Distinctiveness Conflict Risk	Occupies a clear niche (GSD milestone decomposition into vertical slices/tracer bullets) with distinct, specific triggers unlikely to fire for unrelated skills, matching the score-3 anchor.	3 / 3
	Total	12 / 12 Passed

Validation

100%

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 — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: gsd-build/gsd-2
Path: src/resources/skills/decompose-into-slices/SKILL.md
Commit: 33c00aa

Reviewed: about 13 hours ago

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