{"type":"firestarter.listing","listing":{"id":"lst_591yg3oZ","product_name":"Nautilus Ti Black Titanium Fountain Pen","category":"Fountain Pen","description":"\n\nNahvalur Nautilus Ti Black\nFrom the depths of the ocean, the Nautilus resurfaces anew! The Nautilus Ti: Black is made from anodized black titanium, and features the flush cap and portholes that were first imagined for the 365 Anniversary: Plongeur. The Nautilus Ti: Black is likewise equipped with an improved clip and ebonite feed, ensuring the best writing experience we have to offer. Join us as we move a classic design into the future!\n\n\nNahvalur Nautilus Ti Black Fountain Pen Specifications:\nPen Material: Titanium\nTrim: Black\nNib: Stainless steel #6 size or 14K Gold #6 size made by Nahvalur with  ebonite feed, the ebonite feed &amp; housing are different than normal Nahvalur nib unit\n\nFilling Mechanism: Piston-filling (bottled ink only)\nPen Length, Closed: 5.94 in. / 151mm\nPen Length, Open (Cap Off): 5.19 in. / 132mm\nPen Length, Open (Cap Posted): Cannot be posted\nPen Barrel Diameter: 0.57 in. / 14.5mm\nPen Grip Section Diameter: 0.41 in. - 0.44 in. / 10.6mm - 11.3mm\nPen Weight: 1.9 oz. / 54g\nPackaged in a gift box\n","images":["https://cdn.shopify.com/s/files/1/0575/7177/files/Nautilus-Ti-Black-Titanium-Fountain-Pen.jpg?v=1757684780","https://cdn.shopify.com/s/files/1/0575/7177/files/Nautilus-Ti-Black-Titanium-Fountain-Pen-2.jpg?v=1757684876","https://cdn.shopify.com/s/files/1/0575/7177/files/Nautilus-Ti-Black-Titanium-Fountain-Pen-3.jpg?v=1757684811","https://cdn.shopify.com/s/files/1/0575/7177/files/Nautilus-Ti-Black-Titanium-Fountain-Pen-4.jpg?v=1757684852","https://cdn.shopify.com/s/files/1/0575/7177/files/Nautilus-Ti-Black-Titanium-Fountain-Pen-5.jpg?v=1756221116"],"price":199,"currency":"USD","in_stock":true,"inventory_qty":29997,"dynamic_pricing":false,"listed_at":"2026-06-18T20:45:59.573Z"},"share_url":"https://firestarter.network/l/lst_591yg3oZ","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_591yg3oZ' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Nautilus Ti Black Titanium Fountain Pen' and a budget_max comfortably above $199.00 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."]}}