| name | step-decomposition |
| description | Use when a detail implementation plan needs to be split into completely separated subplans for execution. The subplan must be a full, verbatim copy of the phase from the detail plan, without any summarization or omission. |
Step Decomposition
Split the detail plan into discrete sub-plans.
This skill is a strict splitter and copier. Its job is to completely copy the relevant phase from the detail plan into a separate subplan file without summarizing, compressing, or removing any information.
Step decomposition also carries forward full-lifecycle audit state. If execution still depends on unresolved terminology, external claims, or recheck-required knowledge, the subplan must keep that visible.
Purpose
A step subplan should help an executor focus on a single phase of execution without losing any detail or context from the original plan.
If the subplan summarizes or omits details from the original phase, it failed.
Input
- detail plan path
- phase or workstream to extract
- UI constraints inherited from planning when applicable
- current audit blockers or recheck-required items from
task_plan.md and findings.md when relevant
Output
Write to:
docs/plan-for-all/plans/step_subplans/step_subplan_phase{N}.md
Every generated subplan must start with a TDD guard banner that uses the skill name, not a file path:
> Required Skill: Invoke plan-for-all:test-driven-development before executing the detailed steps below.
This stage runs after writing-plans and before execution.
Deterministic Generation (Preferred)
To avoid accidental summarization by free-form generation, prefer deterministic splitting with:
powershell -ExecutionPolicy Bypass -File plan-for-all/scripts/split-step-subplans-verbatim.ps1 -DetailPlanPath docs/plan-for-all/plans/YYYY-MM-DD-<topic>-detail.md
If deterministic generation is available, use it first and only do manual fallback when the script cannot run.
Extraction Rules
- Copy everything explicitly: The subplan must be a full, exact copy of the phase's content from the detailed plan.
- Do NOT summarize.
- Do NOT compress.
- Do NOT remove any details, rationale, examples, or boilerplate.
Do Not Do These
- do not summarize or shorten the content
- do not omit any context or rationale provided in the detailed plan
- do not change acceptance meaning
- do not hide verification behind vague wording
- do not drop unresolved audit items that still affect the active phase
Recommended Subplan Structure
The subplan should mirror the structure of the phase exactly as it appears in the detailed plan, prefixed with the required metadata:
# Phase N: [Name] — Step Subplan
> Source: `docs/plan-for-all/plans/YYYY-MM-DD-<topic>-detail.md`
> Required Skill: Invoke `plan-for-all:test-driven-development` before executing the detailed steps below.
[Exact literal copy of the phase content from the detail plan]
Do not rewrite copied content into template fields such as objective, file list, baseline check, steps, or risks. The phase body must stay in its original structure and wording.
Audit Carry-Forward Rules
If a phase still depends on external knowledge, the subplan must show one of these states explicitly (copied from the detail plan):
verified_official
verified_recent
unresolved
stale_recheck_required
If execution introduces a new suspicious term later, repair the plan and findings rather than quietly editing the subplan in isolation.
Self-Check
Before saving the subplan, verify:
- the subplan starts with the required
plan-for-all:test-driven-development skill banner
- the content is an exact, unsummarized copy of the phase from the detail plan
- no details or rationale were lost or compressed
- active knowledge blockers are still visible when relevant
- the subplan is suitable for a fresh execution session