# Cartroute

> Cartroute is a unified retail search API for AI agents. One request returns matched offers, landed prices, 90-day price history and verified coupon codes from 12 major US retailers as normalized JSON. Free to start with 200 credits.

Cartroute is operated by Cartroute Labs, Inc. (San Francisco, California, United States). Retailers covered: Amazon, B&H Photo, Best Buy, Costco, Lowe's, Micro Center, Newegg, Sam's Club, Staples, Target, The Home Depot, Walmart.
Data source for this deployment: sandbox (synthetic prices for integration testing; every response says so in `data_source`).

## Start here

- [Quickstart](https://cart-route.com/docs/quickstart): get a key and make the first call in under a minute
- [OpenAPI 3.1 spec](https://cart-route.com/openapi.json): every endpoint, parameter and field
- [MCP server](https://cart-route.com/docs/mcp): connect Claude, Cursor or any MCP client to `https://cart-route.com/mcp`
- [Errors](https://cart-route.com/docs/errors): RFC 9457 problem+json with stable codes

## Key facts for an integrating agent

- Auth: `Authorization: Bearer cr_live_...`. New accounts get 100 credits; verifying the email adds 100.
- Cost: 1 credit per successful search, product lookup, price-history or coupon call. Validation errors are free.
- An agent can register for its user with `POST https://cart-route.com/api/v1/accounts`.
- Compare offers on `effective_price_usd` (price + shipping − best coupon needing no special eligibility), not `price_usd`.
- Costco and Sam's Club need a paid membership; pass `include_membership=false` to exclude them.
- Retries: send `Idempotency-Key` to avoid being charged twice.

## Reference

- [Retailers and coverage](https://cart-route.com/retailers)
- [Active coupons](https://cart-route.com/coupons)
- [How prices are compared](https://cart-route.com/guides/how-cartroute-compares-prices)
- [Pricing](https://cart-route.com/pricing)

## Optional

- [Full documentation as one file](https://cart-route.com/llms-full.txt)
- [Changelog](https://cart-route.com/changelog)