{"name":"paperplane","description":"Send real physical mail from an agent or a browser: upload a PDF or plain text, we print it and mail it via USPS. First-Class letters $1.99, Certified Mail $12.99, Certified + electronic Return Receipt $14.99. One all-in price, postage included. No account required — pay per letter via a Stripe link. Free sandbox mode.","url":"https://www.sendpaperplane.com","icon":"https://www.sendpaperplane.com/brand/icon-512.png","version":"1.0.0","capabilities":["physical-mail","usps","certified-mail","letters"],"interfaces":{"mcp":{"transport":"streamable-http","url":"https://www.sendpaperplane.com/api/mcp"},"rest":{"openapi":"https://www.sendpaperplane.com/v1/openapi.json","docs":"https://www.sendpaperplane.com/developers"}},"pricing":{"model":"per-transaction","currency":"USD","items":[{"sku":"first_class","price":1.99,"unit":"letter (1 page B&W)"},{"sku":"certified","price":12.99,"unit":"letter"},{"sku":"certified_err","price":14.99,"unit":"letter"},{"sku":"priority","price":24.99,"unit":"flat-rate envelope"}]},"tools":{"read":[{"name":"quote_letter","effect":"Prices a letter and mints the confirmation token send_letter requires. Creates nothing, costs nothing.","scope":"mail:quote"},{"name":"get_letter_status","effect":"Reads the status of an existing order. Changes nothing.","scope":"mail:read"}],"write":[{"name":"send_letter","effect":"Spends money and mails a physical object to a real address. Not reversible once printed. Requires a confirmation token from quote_letter, bound to the exact recipient, content, class and price.","scope":"mail:send"},{"name":"buy_credits","effect":"Spends a funded agent wallet's own USDC over x402 to buy a prepaid paperplane credit pack, no human checkout step. Mails nothing by itself — the minted credit_code is spent later by send_letter. Settlement on-chain is final; refunds are credit or a voluntary USDC return, never a chargeback.","scope":"mail:send"}]},"authentication":{"required":false,"scheme":"bearer","scopes_supported":["mail:quote","mail:read","mail:send","mail:*"],"scope_by_tool":{"quote_letter":"mail:quote","get_letter_status":"mail:read","send_letter":"mail:send","buy_credits":"mail:send"},"protected_resource_metadata":"https://www.sendpaperplane.com/.well-known/oauth-protected-resource","notes":"A presented key that does not verify is refused, never downgraded to anonymous. Scopes only ever narrow what a caller may do."},"safety":{"mcp_write_tools_require_confirmation":true,"rest_write_requires_confirmation":false,"confirmation":"The MCP send_letter tool requires a single-use, 30-minute confirmation token minted by quote_letter and bound to the recipient, content, mail class and price: a send is never the first call and parameters cannot change in between. POST /v1/orders honours a token when one is supplied but does not yet require one; spend caps bind on both.","spend_caps":"Per-credential daily and monthly spend and volume caps, enforced server-side in the order path and independent of content screening.","content_screening":"https://www.sendpaperplane.com/policy","audit":"Every send is attributed to the calling credential in an append-only trail."},"policies":{"content":"https://www.sendpaperplane.com/policy","terms":"https://www.sendpaperplane.com/terms","privacy":"https://www.sendpaperplane.com/privacy"}}