{"type":"firestarter.listing","listing":{"id":"lst_KC1fST5b","product_name":"SG Ultra","category":"Tennis String","description":"Diadem SG Ultra Set\nDiadem SG Ultra is a signature Synthetic Gut designed to have incredible feel and durability at low cost. Utilizing a unique construction that minimizes fraying, the soft nylon allows for beginners and intermediate level players to take big swings without the risk of losing control. SG Ultra is a great entry-level string in the full and hybrid setups. \nSG Ultra is often used in hybrids with polys such as Flash or Pro X or with nylons such as Impulse and Evolution for remarkable touch. Due to the low stiffness rating it can be used at normal tension.\n\n\n\nLength: 40 ft / 12.2m\n\nColors: Black, Natural\n\nGauges Available:\n\n17 (1.25mm)\n16 (1.30mm)\n\n\n","images":["https://cdn.shopify.com/s/files/1/0253/6210/4402/files/SGUltra_white_combined.jpg?v=1762444779","https://cdn.shopify.com/s/files/1/0253/6210/4402/files/SGUltra_black_combined.jpg?v=1747835860"],"price":6.95,"currency":"USD","in_stock":true,"inventory_qty":39996,"dynamic_pricing":false,"listed_at":"2026-06-20T14:55:57.813Z"},"share_url":"https://firestarter.network/l/lst_KC1fST5b","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_KC1fST5b' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy SG Ultra' and a budget_max comfortably above $6.95 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."]}}