compound-v-plan

name	compound-v-plan
description	Autonomous planning with internal reasoning. Researches, evaluates ideas, presents a plan. Minimizes user round-trips. Use before making non-trivial changes.

Planning Skill

Announce at start: "I'm using the planning skill to work through this."

When to use this skill

• any multi-file change
• any change that impacts behavior, data, auth, billing, or production workflows
• any debugging that needs systematic isolation
• any design decision with multiple viable approaches

Core pattern: think first, ask smart

Planning is LLM-driven, not turn-by-turn. Follow these phases:

Phase 1: Establish the goal

Determine the desired end result — the single sentence that defines success.

• If the user stated a clear goal, use it.
• If the goal is ambiguous, ask ONE question: "What's the desired end result?" and STOP.
• Do NOT ask multiple clarifying questions. Infer what you can and note assumptions.

Phase 2a: Load stack context (sequential — before research)

Read .agents/rules/stack.md if it exists; otherwise read legacy .agent/rules/stack.md. If neither exists, infer versions from go.mod, mix.exs, package.json, or equivalent. These versions scope all subsequent web searches.

If stack.md is missing from both locations, print: "No stack.md found. Run /stack to pin your versions — this improves web search accuracy." Then continue planning.

Phase 2b: Research (autonomous — no user interaction)

Do all of this in parallel (invoke multiple tool calls in the same response):

• Search the web for best practices, alternatives, and pitfalls. Scope to versions in stack.md.
• Read relevant project files to understand structure and patterns.
• Read .promptherder/future-tasks.md if it exists — check if any deferred ideas are relevant.
• Read .promptherder/hard-rules.md if it exists — all rules must be respected.

Phase 3: Think (autonomous — no user interaction)

For each approach you consider, evaluate:

• Idea: what is it?
• Pros: why it's good
• Cons: why it's risky or complex
• Verdict: accept / reject / ask (need user input)

Apply these filters yourself:

• DRY — Identify repeated logic across the plan. Extract shared patterns into reusable steps. If two steps do the same thing, merge them. Update logic in one place — changes reflect everywhere.
• YAGNI — Only plan features you actually need right now. Focus on current requirements, not hypothetical future ones. If a step exists "just in case," cut it.
• Don't overengineer — Focus on the simplest solution that solves the core problem. Ask: "What's the minimum viable version?" If a step adds complexity without clear necessity, skip it. Keep it lean, functional, and maintainable.
• Confirm the approach solves the actual problem, not a hypothetical one.
• Identify risks and verify they are manageable.
• Ensure rollback options exist.

Reject bad ideas yourself. Only surface ideas with verdict ask to the user.

Persist decisions

Write the full decisions table to decisions.md. The calling workflow determines the full path (typically .promptherder/convos/<slug>/decisions.md):

# Decisions: <title>

| #   | Idea | Verdict  | Pros | Cons | Rationale |
| --- | ---- | -------- | ---- | ---- | --------- |
| 1   | ...  | accepted | ...  | ...  | ...       |
| 2   | ...  | rejected | ...  | ...  | ...       |
| 3   | ...  | ask      | ...  | ...  | ...       |

Update this file whenever decisions change (feedback, re-planning, etc.).

Verdicts:

• accepted — you're confident this is right. Include in plan.
• rejected — you've killed it. Visible when user says SHOW DECISIONS.
• ask — you genuinely can't decide without user input. Surface as a batch question.

Phase 4: Present the plan

Present the plan in a single response:

# Plan: <title>

> **Status**: draft

## Goal

<one sentence>

## Plan

### 1. Step name

- **Files:** `path/to/file`
- **Change:** what changes (1-2 bullets)
  - Test → Code → Verify order
- **Verify:** command to verify

## What this builds

### Happy path

1. [numbered walkthrough of user-facing flow after implementation]

### Filesystem tree

[tree showing files created/modified]

## Risks & mitigations

- Risk → mitigation

## Rollback plan

<how to undo>

## References

- Full plan: `.promptherder/convos/<slug>/plan.md`
- Decisions: `.promptherder/convos/<slug>/decisions.md`

Batch questions

After the plan, present all decisions you need input on in one block:

**I need your input on:**

1. <question> — I recommend (A) because ...
   - (A) option
   - (B) option
2. <question>
   - (A) ...
   - (B) ...

If the path is clear, skip this section.

Deferred ideas

If you identified ideas with future value, list them:

**Ideas I'd defer to future tasks:**
- <idea> — <brief rationale>

Add these to future-tasks.md? yes / no

Only append after the user confirms.

Anti-patterns (don't do these)

• ❌ Asking the user to ACCEPT/REJECT individual ideas one at a time
• ❌ Showing the decisions table before you've done your own thinking
• ❌ Asking clarifying questions you could answer by reading the code
• ❌ Multiple rounds of "does this look right?" on sections of the plan
• ❌ Deferring the goal statement to a later phase
• ❌ Silently adding deferred ideas without confirmation

Good patterns

• ✅ Research first, then present a confident plan
• ✅ Batch all questions into one block at the end
• ✅ Offer SHOW DECISIONS audit on demand (not by default)
• ✅ Kill bad ideas yourself with rationale (visible in audit)
• ✅ State assumptions explicitly so the user can correct them
• ✅ Confirm deferred ideas with the user before adding to future-tasks.md
• ✅ Include "What this builds" section with happy path and filesystem tree

Planning rules

• Steps should be small (2–10 minutes each).
• Every step must include verification.
• Each step must show test → code → verify order where applicable.
• If the plan changes the codebase structure, show a before/after filesystem tree.
• Prefer incremental deliverables (avoid "big bang" edits).
• Identify rollback and risk controls early.
• Group independent steps for parallel execution where possible.
• Never write to stack.md without user approval.
• State the goal first. Everything else flows from it.

Plan step format

### 1. Step name
- **Files:** `path/to/file.ext`, `...`
- **Change:** (1–2 bullets)
  - Test: what test to write first
  - Code: what to implement
- **Verify:** (exact commands or checks)