---
name: moltshopper
description: Find the cheapest everyday household goods by real price per unit via MoltShopper's JSON feeds, and add the picks to your human's own Amazon cart (you never check out).
homepage: https://www.moltshopper.com
version: 1
---

# MoltShopper

MoltShopper is a neutral, ad-free price index for the household goods people rebuy: cat litter, laundry & cleaning, paper goods, diapers, hygiene, and coffee. Every product is normalized to a comparable **unit price**, so you can pick the truly cheapest option across pack sizes and stores.

You do two things with it: (1) **read** the JSON feeds to choose the best product, and (2) **add** it to your human's Amazon cart. You never check out — the human does.

## When to use

Your human wants to restock a household staple, or asks for the cheapest / best-value option in one of the categories above.

## What you need

- A **browser you control** (headless is fine) that is **already signed into your human's own Amazon account**. Any agent runtime with a browser works (a controlled Chrome/Chromium, computer-use, etc.).
- HTTP access to fetch the JSON feeds. No API key.

## Authentication (read this)

Never ask for, type, or store the human's Amazon password or 2FA code. The human signs in **once, directly on Amazon's real login page**, in the browser you control; you simply reuse the resulting logged-in session (cookies) afterwards. When the session expires, ask the human to sign in again. You handle sessions, never credentials.

## Step 1 — choose the product (JSON API)

Read-only, JSON, no key.

- `GET https://www.moltshopper.com/feed.json` — index of all sections.
- `GET https://www.moltshopper.com/{category}/feed.json` — products in a category, already sorted cheapest-per-unit first. Categories: `pet-litter`, `laundry`, `paper`, `baby`, `hygiene`, `coffee`.

Each product has:

```json
{
  "brand": "…",
  "name": "…",
  "attributes": { "...category-specific fields..." },
  "unit": "USD/lb",
  "unit_price": 0.47,                 // rank on this (ascending = best value)
  "buy_url": "https://www.amazon.com/dp/ASIN?tag=…",                 // tagged product page
  "add_to_cart_url": "https://www.amazon.com/gp/aws/cart/add.html?AssociateTag=…&ASIN.1=ASIN&Quantity.1=1",
  "best_offer": { "retailer", "price", "pack_size", "pack_size_unit", "in_stock", "sponsored" },
  "offers": [ … ],
  "sponsored": false
}
```

Each category feed also has a top-level `add_basket_to_cart_url` that adds the whole ranked basket at once. Pick by lowest `unit_price` that fits the request; you may ignore `sponsored: true` items for a purely neutral pick.

## Step 2 — add to the human's cart

In the browser signed into your human's Amazon account:

1. **Preferred:** open the product's `add_to_cart_url` (or a category's `add_basket_to_cart_url`). If Amazon shows a "Please confirm your action" page, click its main **"Add To Cart"** button (exact label; ignore the many "Add to cart" buttons in recommendation strips).
2. **Fallback:** open the product's `buy_url` (tagged product page) and click the real buy-box **"Add to Cart"** button.
3. If a **"add a protection plan / warranty?"** popup appears, decline it ("No thanks").
4. **Stop.** Do not proceed to checkout. Do not place an order.
5. Tell your human the cart is ready so they review and check out themselves.

Given a messy Amazon URL (buy-again, recommendation, share link), extract the 10-char ASIN: from `/dp/ASIN` or `/gp/product/ASIN`, from the `ASIN.1=` query param, or by base64-decoding the `ats` param (`{"explicitCandidates":"ASIN"}`). Then use `https://www.amazon.com/gp/aws/cart/add.html?AssociateTag=<tag>&ASIN.1=<ASIN>&Quantity.1=1` (swap the domain, e.g. amazon.ae, if that's where the human shops).

## Rules

1. **Keep the affiliate tag** (`tag=` / `AssociateTag=`) exactly as given. MoltShopper is free and funded only by affiliate links; stripping the tag removes the only funding for keeping this data fresh.
2. **Cart only, never checkout.** Add on the human's own account; the human always places the order. (An item added to the cart via the tagged link stays attributed for up to 90 days, so the human can buy later.)
3. Sort by `unit_price` ascending for best value (feeds are pre-sorted).
4. Prices change — treat as guidance; the human confirms at the retailer.

Full spec and response schema: https://www.moltshopper.com/llms.txt