{"type":"firestarter.listing","listing":{"id":"lst_MsltiaPB","product_name":"Kaweco Piston Classic Sport Fountain Pen - Black","category":"Fountain Pen","description":"The Kaweco Piston Sport Classic is made of high-quality plastic in Germany, assembled and tested by hand. The lightweight material and the optimal pen length with the cap attached allow the writing instrument to glide effortlessly over the paper and the hand not to tire even after long periods of writing. The nib unit, which is perfectly matched to the fountain pen, ensures a rich ink flow and thus provides a particularly soft writing feel. The combination with gold decorative elements extends the functionality with stylish elegance, thus uniting traditional filling methods with the modern age.\nThe Kaweco Sport piston fountain pen is the smallest of its kind due to its sophisticated and compact mechanism in terms of the ratio of pen size to ink filling volume. This iconic pocket fountain pen measures just 10.5 cm when closed and grows to a normal size of 13 cm when the cap is turned. Its small size makes it ideal for on the go and ensures a long and pleasant writing experience.\nThe transparent ink window allows you to keep an eye on the ink level at all times. If the ink runs out, the piston fountain pen can be refilled quickly and easily thanks to the particularly smooth filling mechanism. This filling system also allows you to use inks in an unrivalled range of colors, as there are many ink colors that are only filled in glass jars.\n\nAll custom nib grinds are not factory-made; they are customized by us and are not covered under warranty or service by the producer. For warranty and service matters, Galen Leather is responsible.","images":["https://cdn.shopify.com/s/files/1/0575/7177/files/Kaweco-Piston-Classic-Sport-Fountain-Pen-Black.jpg?v=1737217483","https://cdn.shopify.com/s/files/1/0575/7177/files/kaweco-custom-nibs.jpg?v=1737988960","https://cdn.shopify.com/s/files/1/0575/7177/files/kaweco-custom-grinds-writing-samples.jpg?v=1737988960","https://cdn.shopify.com/s/files/1/0575/7177/files/Kaweco-Piston-Classic-Sport-Fountain-Pen-Black-2.jpg?v=1737988960","https://cdn.shopify.com/s/files/1/0575/7177/files/Kaweco-Piston-Classic-Sport-Fountain-Pen-Black-3.jpg?v=1737988960","https://cdn.shopify.com/s/files/1/0575/7177/files/Kaweco-Piston-Sport-AL-Fountain-Pen-Navy-4.jpg?v=1775662656"],"price":98,"currency":"USD","in_stock":true,"inventory_qty":29997,"dynamic_pricing":false,"listed_at":"2026-06-18T20:45:59.923Z"},"share_url":"https://firestarter.network/l/lst_MsltiaPB","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_MsltiaPB' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Kaweco Piston Classic Sport Fountain Pen - Black' and a budget_max comfortably above $98.00 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."]}}