Feature Plan Skill

Create feature documentation in DevPlans/Features/ to capture discussed features for future implementation.

Important: Only create a feature plan when the user explicitly requests it.

Investigation First

Before writing the feature plan, launch an Explore subagent using the Task tool to investigate the codebase thoroughly:

code

Task tool with subagent_type: "Explore"
model: "opus"
prompt: "Investigate the codebase to understand how to implement [feature description]. Find:
- Existing systems this feature would integrate with
- Similar patterns or features already implemented
- Data structures and classes that would be involved
- Entry points where the feature would hook in
- Any existing TODOs or comments related to this feature area
- Architectural patterns used in similar areas"

Use the investigation results to fill in the Design, Key Components, and Integration Points sections with concrete findings from the codebase rather than generic suggestions.

File Naming

{STATUS}-{FeatureName}.md

Status	Meaning
PLANNED	Feature documented, not yet started
IN_PROGRESS	Currently being implemented
DONE	Feature has been implemented
CANCELLED	Won't implement

New features should always start with PLANNED-.

Required Sections

markdown

# Feature: {Title}

## Summary
Brief description of what this feature does and why it's needed.

## Goals
- What this feature should accomplish
- User-facing benefits
- Technical benefits

## Design

### Overview
High-level description of the approach.

### Key Components
- List main classes/systems involved
- New files to create
- Existing files to modify

### Data Structures
Describe any new structs, classes, or data formats needed.

### Behavior
How the feature works step-by-step.

## Integration Points
- How this connects to existing systems
- Dependencies on other features
- Systems that will depend on this

## Open Questions
- Unresolved design decisions
- Areas needing further discussion

## Priority
Low / Medium / High

## Related Files
- `path/to/related/file.cs`

Example

For a belt conveyor feature:

•File: DevPlans/Features/PLANNED-BeltSystem.md
•Title: # Feature: Belt Conveyor System
•Include diagrams or ASCII art if helpful

Status Changes

When implementation status changes, rename the file:

•PLANNED-MyFeature.md → IN_PROGRESS-MyFeature.md
•IN_PROGRESS-MyFeature.md → DONE-MyFeature.md
•PLANNED-MyFeature.md → CANCELLED-MyFeature.md