Plan from PRD
Turn a PRD into a phased implementation plan using vertical slices (tracer bullets). Output is a local Markdown file in ./plans/.
Skill workflow — this skill fits in the middle: create-prd → pre-mortem *(optional)* → plan-from-prd → prd-slice *(push slices to a tracker)*
Not what you need? If you want to create GitHub Issues / Azure DevOps work items / Jira tickets directly from the PRD, use prd-slice instead.Process
1. Confirm the PRD is in context
The PRD should already be in the conversation. If it isn't, ask the user to paste it or point you to the file.
2. Explore the codebase
If you have not already explored the codebase, do so with a subagent to understand the current architecture, existing patterns, and integration layers.
3. Identify durable architectural decisions
Before slicing, identify high-level decisions that are unlikely to change throughout implementation:
- Route structures / URL patterns
- Database schema shape
- Key data models
- Authentication / authorization approach
- Third-party service boundaries
These go in the plan header so every phase can reference them.
4. Draft vertical slices
Break the PRD into tracer bullet phases. Each phase is a thin vertical slice that cuts through ALL integration layers end-to-end, NOT a horizontal slice of one layer.
When the PRD is large or complex — many stories, broad surface area, or multiple cross-cutting concerns — group phases into waves. The first wave must deliver a demonstrable, MVP-sufficient experience on its own. Subsequent waves add depth and breadth. When grouping phases within a wave, prefer phases that share no blocking dependencies so they can proceed in parallel.
5. Quiz the user
Present the proposed breakdown as a numbered list. For each phase show:
- Title: short descriptive name
- User stories covered: which user stories from the PRD this addresses
Ask the user:
- Does the granularity feel right? (too coarse / too fine)
- Should any phases be merged or split further?
- If waves were proposed: does Wave 1 represent a sufficient MVP? Are the wave boundaries right?
Iterate until the user approves the breakdown.
6. Write the plan file
Create ./plans/ if it doesn't exist. Write the plan as a Markdown file named after the feature (e.g. ./plans/user-onboarding.md). Use the template below.
Source PRD:
Architectural decisions
Durable decisions that apply across all phases:
- Routes:...
- Schema:...
- Key models:...
- (add/remove sections as appropriate)
Wave 1: MVP *(omit wave headers if no wave grouping)*
Phase 1:
User stories:
What to build
A concise description of this vertical slice. Describe the end-to-end behavior, not layer-by-layer implementation.
Acceptance criteria
- Criterion 1
- Criterion 2
- Criterion 3
Phase 2:
User stories:
What to build
...
Acceptance criteria
- ...
Wave 2: *(omit if no wave grouping)*
Phase 3:
User stories:
What to build
...
Acceptance criteria
- ...
The skill's work is complete when the plan file is saved and the user has confirmed the phase breakdown. Return control to the user.