create-plan

name	create-plan
description	Create detailed implementation plans with thorough research and iteration. Use when starting significant features spanning multiple files, planning refactors affecting architecture, working on multi-phase projects with milestones, establishing success criteria before coding, breaking down complex work, or documenting approach for non-trivial technical decisions.

Create Implementation Plan (Generic)

Workflow

1. Understand the Requirement

• Read all mentioned files completely (no partial reads)
• Present your informed understanding with specific file:line references
• Ask focused questions only about what research couldn't clarify
• Don't ask questions answerable through code exploration

2. Decompose and Plan Research

• Break task into composable research areas
• Identify components, patterns, concepts to investigate
• Use TodoWrite to track subtasks
• Think deeply about underlying patterns and constraints

3. Spawn Parallel Sub-Agents

Codebase Research:

• codebase-locator - Find WHERE files/components live
• codebase-analyzer - Understand HOW existing code works
• codebase-pattern-finder - Find similar implementations to learn from

Agent Tips:

• Start with locator agents to find what exists
• Use analyzer agents on promising findings
• Run multiple agents in parallel
• Tell agents what you're looking for, not how to search

4. Wait and Synthesize

Wait for ALL sub-agents, then:

• Compile results, prioritize live codebase as source of truth
• Include file paths and line numbers
• Highlight patterns, connections, architectural decisions
• Answer questions with concrete evidence

5. Propose Plan Structure

Present outline for approval:

## Overview
[1-2 sentence summary]

## Implementation Phases:
1. [Phase Name] - [What this accomplishes]
2. [Phase Name] - [What this accomplishes]
3. [Phase Name] - [What this accomplishes]

Get explicit user buy-in before investing in detailed planning.

6. Write the Plan

Save to: thoughts/shared/plans/YYYY-MM-DD-brief-description.md (if thoughts/ exists) Or present inline if no thoughts directory.

Structure:

• Overview - Brief goal description
• Current State Analysis - What exists (file:line refs), what's missing, constraints
• Desired End State - What "done" looks like
• Key Discoveries - Findings with file:line refs
• What We're NOT Doing - Out-of-scope items
• Implementation Approach - High-level strategy

Per phase:

• Overview, changes required (file + specifics), success criteria, confirmation gate

End with:

• Testing Strategy - Unit, integration, manual
• References - Tickets, research, code refs

7. Finalize

• Run humanlayer thoughts sync (if applicable)
• Present draft location to user
• Iterate on feedback

Success Criteria Format

Automated: Tests, type check, lint, build

Manual: Feature works, performance acceptable, edge cases handled

Key Principles

• File:line references and measurable criteria
• Phases with confirmation gates
• Research before proposing
• Consider backwards compatibility
• No open questions - research or ask first

Common Implementation Patterns

Database Changes: Schema → Store/Repository methods → Business logic → API endpoints → Client code

New Features: Research patterns → Data model → Backend implementation → API → UI/Frontend

Refactoring: Document current state → Incremental changes → Maintain backwards compatibility → Migration strategy

API Changes: Document current behavior → Deprecation plan → New implementation → Migration guide → Old code removal