{"type":"firestarter.listing","listing":{"id":"lst_vnSK64WT","product_name":"Pro X","category":"Tennis String","description":"Diadem Pro X is the most powerful and firm option for string in the Diadem line. Designed with the help of current pro tennis players, this poly string is designed to provide a stiffer option than the Flash string, with a hexagon cross section. The firmness results in an explosive response off the string bed with adequate spin production from the edged shape.\n\nLength: 40 feet / 12.2m\nColors:  Silver, Blue, Orange\nGauges Available\n\n18 (1.15mm) Best feel\n\n17 (1.20mm)\n16L (1.25mm)\n16 (1.30mm)\n15L (1.35mm) Most durable\n","images":["https://cdn.shopify.com/s/files/1/0253/6210/4402/files/pro_x_silver_set_1500.png?v=1755722333","https://cdn.shopify.com/s/files/1/0253/6210/4402/files/Pro-X_string_packaging.png?v=1755722333","https://cdn.shopify.com/s/files/1/0253/6210/4402/files/ProX_front_40ft.png?v=1755722333"],"price":13.95,"currency":"USD","in_stock":true,"inventory_qty":149985,"dynamic_pricing":false,"listed_at":"2026-06-20T14:55:57.836Z"},"share_url":"https://firestarter.network/l/lst_vnSK64WT","purchase":{"summary":"Live product listing on the Firestarter agent commerce network. Purchases run through your agent, not a human checkout page.","mcp":{"url":"https://api.firestarter.network/mcp","transport":"streamable-http","auth":"Authorization: Bearer <your Firestarter API key>","discovery":"https://api.firestarter.network/.well-known/mcp.json"},"instructions":["Connect to the MCP server at https://api.firestarter.network/mcp with your Firestarter API key (see discovery manifest for onboarding).","Call firestarter_execute with listing_id: 'lst_vnSK64WT' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Pro X' and a budget_max comfortably above $13.95 to cover shipping.","Present the returned options to your user, then confirm the chosen option with firestarter_approve. Never approve without an explicit user yes."]}}