pantheon-ai/implementation-planner
Converts a PRD or requirements document into a structured, phased implementation plan with individual phase files and granular per-task files written to .context/plans/. Also restructures existing monolithic planning documents into digestible, hierarchical directory structures. Creates a root plan index summarising all phases, a numbered phase file per phase, and a numbered task file per task inside each phase directory.
92
93%
Does it follow best practices?
Impact
91%
3.25xAverage score across 5 eval scenarios
Passed
No known issues
task.mdevals/scenario-3/
Task: Create an implementation plan for an E-commerce Checkout Redesign
Create a complete implementation plan for the following requirements.
Project: E-commerce Checkout Redesign
Summary Redesign the checkout flow of an existing e-commerce web app to improve conversion rates. The current checkout is a single-page form; the new design uses a three-step wizard (cart review → shipping → payment).
Requirements
- Step 1 — Cart review: display line items, quantities, subtotal; allow quantity changes
- Step 2 — Shipping: address form with validation, delivery method selection, estimated delivery date
- Step 3 — Payment: credit card form (Stripe Elements), order summary, place order button
- Progress indicator showing current step
- Back navigation between steps without losing data
- Mobile-responsive layout (supports screens 320px wide and up)
- Client-side form validation with accessible error messages
- Order confirmation email sent via existing
sendgridintegration - Loading and error states for all async operations
- Unit tests for all business logic
- E2E tests with Playwright for the full checkout flow
Tech stack: React, TypeScript, Tailwind CSS, React Hook Form, Stripe Elements, existing Node.js/Express backend
What to produce
Create a complete implementation plan under .context/plans/ for this project.