# Hidden cost at checkout — dev spec
Site: allbirds.com · Priority 6 · Urgent · Effort: Medium (2-5 days)

## Problem
The product page does not display the price, and the cart drawer reveals a $5 shipping fee, creating a hidden cost that may deter purchase.

## Evidence (from the live site)
> Product page CTAs include 'Get Notified' and 'Learn More' but no price; cart drawer states 'Shipping $5.00'.

## Current state
h1: Anytime Ankle Sock; cta: Get Notified | Learn More; notes: No price visible on product page; shipping cost only appears in cart.

## Required change
h1: Anytime Ankle Sock; cta: Add to Cart; notes: Display price and free shipping threshold (e.g., 'Free shipping over $100') on product page.

## Acceptance criteria
- GIVEN a first-time visitor on the affected page
- WHEN the change is live
- THEN Display price and free shipping threshold (e.g., 'Free shipping over $100') on product page.
- AND no layout regression at 375px / 768px / 1280px
- AND the changed control is keyboard-reachable with an accessible name

## Tracking
- Fire `cro_hidden_cost_at_checkout` on interaction with the changed element
- Verify the event fires in BOTH variants before opening traffic

## Test plan
- Two-proportion z-test, 95% significance, 80% power
- 118,817 visitors per variant to detect a 8.0% relative lift
- Run at least one full business cycle; 40 days

## Rollback
Feature-flag the change; revert if the primary metric drops for 3 consecutive days.