For AI agents and developers

AI assistants, shopping agents and scripts can search our catalog, check what fits, and hand a shopper a ready-to-pay cart. No key or sign-up is needed. Everything here is read-only: these tools never place an order or charge a card. The shopper opens the cart link, enters the address and pays on the normal checkout page.

MCP server

Remote MCP server (Streamable HTTP, no auth): https://www.madmaxsupply.com/mcp

Tools: search_parts, get_product, check_fit, create_checkout_link, list_categories, get_store_policies.

Add it to an MCP client as a remote/custom connector with that URL. Server card: /.well-known/mcp.json.

REST API (OpenAPI 3.1)

Spec: /openapi.json. CORS is open.

• GET /api/agent/search?q=<keywords, OEM part no. or size>&ship_to_state=MN, for example search WF3CB
• GET /api/agent/fit?q=20x25x4: what we carry for an OEM part number, filter size or model name
• GET /api/agent/product/<SKU>: price for the ship-to state, shipping, return window, auto-ship options
• GET /api/agent/checkout-link?items=SKU:qty[:months],...&ship_to_state=MN (or POST JSON): returns a pre-filled cart_url
• GET /api/agent/policies and GET /api/agent/categories

Cart links

https://www.madmaxsupply.com/cart/?add=MM-RF-891B5F:1,MM-AF-7859F0:2:6 opens the cart with those items. The optional third value sets Subscribe & auto-ship (1, 2, 3, 6 or 12 months) on eligible items. We email a notice before any price change on a subscription.

Prices, shipping and tax

Prices are in USD. No sales tax is added at checkout because item prices already include the tax we pay, so the API takes ship_to_state and prices can differ slightly by state. Most items include shipping within the contiguous US. AK, HI, US territories and APO/FPO addresses get a shipping quote and a payment link before any charge. One-time orders are authorized at checkout and charged when the order is confirmed in stock. Returns: see each item's window and our terms.

Feeds and data

• catalog.json (full catalog), replacements.json (OEM part cross-reference from product titles), filter-sizes.json
• Product feeds: Google Merchant XML, Bing TSV, OpenAI-format JSONL (also JSON)
• llms.txt, llms-full.txt, /.well-known/api-catalog, /.well-known/ai-plugin.json

Good-bot rules

Please keep it under about one request per second, cache what you can (catalog data changes at most a few times a day), and never tell a shopper an order was placed until they have paid at checkout. Fit matches come from product titles, so ask the shopper to confirm against the old part. Questions or a bulk/API need: tamara@madmaxsupply.com.