gsa9/step2

/step2

Create _step2_plan.md at repo root. This file is the sole input for /step3 subagents, which have zero prior context.

Gates

1. Tools: Read, Glob, Grep only. Never use Agent, Task, or EnterPlanMode/ExitPlanMode.
2. No code. The only output is _step2_plan.md.
3. Do not mention /step3 until _step2_plan.md is written and _step1_decisions.md is deleted.
4. Never use AskUserQuestion. Ask in plain text with numbered options, one question per message.

Flow

1. LOAD

Read _step1_decisions.md.

If found: transform it, do not copy it. Convert decisions into phase-level tasks. Convert pitfalls and rejected alternatives into guardrails phrased as "Do NOT use X because Y". Embed each ## Constraints entry as a Guardrail in every phase that could violate it.

If not found: use conversation context or ask the user.

2. RESEARCH

Read relevant source files referenced in the decisions document or identified from the goal.

3. DESIGN + WRITE

Design all phases, then write the complete _step2_plan.md in one Write call.

Phase design rules:

1. Default to one phase per deliverable. Only split a deliverable across phases when partial output creates a dependency needed by a later phase.
2. Independent deliverables go in the same parallel group for concurrent execution. Phases in the same group must not share outputs.
3. Each phase is dispatched to an isolated subagent that sees only the Rationale section plus its own Phase Details. Therefore: use explicit deliverable names, one clear objective, and concrete tasks. The overview table is for orchestration only and is not dispatched.
4. Any shared context (definitions, constraints, formats) must be embedded in each phase that needs it, not placed at plan level.

4. CLEANUP

Do not output anything during these operations.

Delete _step1_decisions.md via Recycle Bin (never permanent delete).

On Windows, delete _step1_decisions.md:

powershell -NoProfile -Command 'Add-Type -AssemblyName Microsoft.VisualBasic; [Microsoft.VisualBasic.FileIO.FileSystem]::DeleteFile((Join-Path "WORKING_DIR" "_step1_decisions.md"),"OnlyErrorDialogs","SendToRecycleBin")'

Verify the file is gone. Show the output box. Stop.

Code-Task Overrides

When _step1_decisions.md contains code-task: true, apply these overrides:

1. Phase granularity: one phase per file instead of per deliverable. Target 50-150 dispatched lines per phase. If larger, split.
2. Phase template labels: use **Modifies:** and **Reference:** instead of **Outputs:** and **Inputs:**.
3. Overview table: add an Est. Lines column.
4. Prefer LLM-dev-friendly patterns: flat logic, named constants, no indirection, inline single-caller helpers.

Format

Use this structure for _step2_plan.md:

---
code-task: true  # only if _step1_decisions.md has code-task: true
title: [from _step1_decisions.md frontmatter]
---
<!-- @plan: /step2 -->
# [Goal Title]

**Goal:** [1-2 sentences]

## Rationale

**Approach:** [chosen approach]
**Why:** [key reasons from evidence]
**Patterns:** [conventions subagents must follow]
**Constraints:** [what must hold true and why — from `## Constraints` in decisions]

## Phases Overview

| Phase | Name | Depends | Parallel Group |
|-------|------|---------|----------------|
| 1 | ... | - | A |
| 2 | ... | 1 (produces X) | B |

## Phase Details

### Phase N: [title]
**Outputs:** [exact deliverable names/paths]
**Inputs:**
- `source/or/reference` — [what to look at and why]
**Guardrails:**
- [constraint from `## Constraints` that this phase could violate — with WHY]
- [pitfall or rejected alternative phrased as "Do NOT X because Y"]
**Tasks:**
- [ ] Concrete task 1
- [ ] Concrete task 2

Output:

[title]

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