{"type":"firestarter.listing","listing":{"id":"lst_i4d8v4Fw","product_name":"Model 31 Omnis Fountain Pen - Black Cathedral","category":"Fountain Pen - Model 31","description":"\nThis edition features our Black acrylic complimented by the Cathedral material for the finial. Cathedral harkens the colors often found in stained glass, with deep reds, blues, golds, and greens. \n\n\nThe Model 31 fountain pen encompasses features from several F-C models. The grip section is like that of the 40 Panther, the silhouette is a slightly slimmer version of the 19, precision posting like the 20, 45, and 03, cut grooves and recessed nib like the 20. \n\n♦ Dimensions:.625\" cap diameter (15.87mm).531\" upper barrel diameter (13.49mm)5.50\" capped length (139mm)6.755\" cap posted length including nib (172mm)5.250\" barrel length including nib (133mm) .41-.47\" thick grip section at thinnest and thickest point (10.4 - 11.92mm)Weight without ink = .92oz / 26.08g\n\n\n♦ Made in USA of long lasting, durable hard acrylic that is light weight. ♦ Standard Int'l Cartridge / Converter filled, one of each included. Also can be used as an eyedropper. Barrel holds approximately 3.5ml of ink when eyedroppered.♦ #6 Size nib - with many tip options in factory or custom ground. ♦ Lifetime Warranty. ♦ Shipped with a Franklin-Christoph single pen zippered pouch with an outer white thin box. \n","images":["https://cdn.shopify.com/s/files/1/0023/7679/4187/files/31BlackCathedralFountainPen.jpg?v=1764612822","https://cdn.shopify.com/s/files/1/0023/7679/4187/files/31BlackCathedralFPside.jpg?v=1764612822","https://cdn.shopify.com/s/files/1/0023/7679/4187/files/FPorderinclusions_b23e09b3-b75c-47ea-8fbb-87871340b2c8.jpg?v=1764612822"],"price":160,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-18T20:47:20.459Z"},"share_url":"https://firestarter.network/l/lst_i4d8v4Fw","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_i4d8v4Fw' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Model 31 Omnis Fountain Pen - Black Cathedral' and a budget_max comfortably above $160.00 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."]}}