{"type":"firestarter.listing","listing":{"id":"lst_zvAF9AYn","product_name":"Sailor Kiwa-guro - Waterproof Pigment Ink","category":"Ink","description":"Sailor’s Kiwa-guro is a beautifully deep, archival black from one of Japan’s most respected ink makers.\nFormulated with ultra-fine pigment particles, it offers excellent permanence, strong water resistance, and a slightly faster drying time than our No. 60 Pigment Ink. The result is an intensely dark, velvety line that works beautifully for detailed drawing and layered work.\nPerformance &amp; care – a quick heads up\nBecause this is a pigment-based ink, it behaves a little differently from our dye-based fountain pen inks.\n\nIt’s compatible with all of our pens – The Lumos, Wren, Field Mouse and our Fountain Pens. If you’re using the finest fineliner tips in the Lumos (0.4 and below), here are a few helpful pointers:\n\n\nIf you won’t be using your pen for more than a few days, remove the tip and reservoir, rinse thoroughly with water, and allow everything to dry completely before refilling.\nAvoid storing your Lumos vertically (tip up). Ink can flow away from the nib, leaving it less saturated and more prone to drying out – even when capped.\nIf pigment ink dries inside a tip or reservoir, it can’t be revived due to the pigment particles. Simply replace the tip and reservoir and you’re back in business.\n\n\nA little care goes a long way. In return, you’ll get crisp, permanent, archival black lines.\n\n\n*Waterproof? Almost. This ink is highly water-resistant once fully dry. It will hold beautifully under a light to moderate colour wash. Very heavy, very wet overwashes may cause slight movement, so we always recommend testing before committing final marks to the page.\n","images":["https://cdn.shopify.com/s/files/1/0089/6129/4417/files/sailor-kiwa-guro-waterproof-pigment-ink-black.jpg?v=1745323415"],"price":31,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-18T20:47:23.525Z"},"share_url":"https://firestarter.network/l/lst_zvAF9AYn","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_zvAF9AYn' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Sailor Kiwa-guro - Waterproof Pigment Ink' and a budget_max comfortably above $31.00 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."]}}