Update to Mail by Pony

{
  "description": "Write letters with Mail by Pony, check the exact print proof, then send them from a prepaid balance or a one-click payment link.",
  "included_files": [],
  "name": "send-letter",
  "skill_md_contents": "---\nname: send-letter\ndescription: Write letters with Mail by Pony, check the exact print proof, then send them from a prepaid balance or a one-click payment link.\n---\n\nUse the connected Mail by Pony MCP tools; never invent tool results or claim the\nplugin is connected before a call succeeds. If agent access is unavailable, show\nthe actual setup status and stop dependent operations.\n\nAccept only ordinary non-sensitive correspondence. Do not request medical\nrecords, government identifiers, card data, passwords or secrets. State the\ncontent boundary before uploading a PDF or photo; the owner must acknowledge it.\nUploaded art is decoration, not purchased postage.\n\nRead catalog and existing drafts first. Keep text, Markdown and uploaded PDF\nformats explicit. Preserve the latest revision and use a fresh idempotency key\nfor each intended mutation; reuse the same key when checking/retrying it. Never\noverwrite a conflict or blindly repeat an uncertain mutation.\n\nFor editable multipage letters, use pages with stable IDs and explicit text or\nMarkdown format. Preserve IDs while editing/reordering; a source may flow onto\nseveral printed sheets. Read the actual preview's page_map before placing art;\nanchor it with page_id/page_offset so earlier edits do not move it to another\nsource page. Legacy text-only updates replace explicit pages. PDF mode prints\nthe uploaded original while retaining editable pages for switching back.\nPreserve the returned handwriting seed and engine_version when reopening or\ncopying handwritten work; change its seed only for an intentional new variation.\nThe experimental original_hand style has a separate original_hand seed/engine/\nfoundation configuration. Check catalog readiness and its exact supported\ncharacters before offering it, retain its experimental/provenance limits, and\npreserve both configurations when copying. Never silently replace unsupported\ncharacters or substitute another visible font.\n\nCollect sender and recipient addresses in conversation and save them with\ncreate_draft/update_draft (or reuse IDs from list_address_references). Ask only\nfor fields listed in address_validation. Never guess a ZIP or claim postal\nverification. Never infer ownership from matching email addresses.\n\nRun preview for the exact proof and tell the person what will print: pages,\nrecipient, options and price. Use show_letter only if they ask for an inline\npreview; tool success does not prove the panel rendered.\n\nWhen the person says to send it:\n- If catalog.prepaid.sending_ready is true and list_agent_grants shows an active\n  permission for this assistant, call quote_for_send for the final total, then\n  send_with_credits with the same idempotency key on any retry.\n- Otherwise call create_payment_link and give them the checkout_url. Paying that\n  Stripe page approves and sends the letter.\n- On INSUFFICIENT_FUNDS share the returned funding link or offer a payment link.\n  On grant_required offer a payment link, or tell them they can allow this\n  assistant in Account → Credits.\n\nThe website review (handoff_url) and the prepare_checkout/checkout tools remain\navailable for people who prefer to finish there.\n\nNever claim a letter was paid, printed or mailed unless get_order says so.\nQueued is not mailed; mailed means handed to USPS, not delivered. Cancel only\nwhen eligible and explicitly requested. Developer docs:\nhttps://www.mailbypony.com/developers .\n\nA dedicated reviewer account uses owned synthetic drafts and Stripe test-mode\npayment links. Use create_payment_link only when the reviewer asks to send;\nclearly state that no real money moves and test orders are never printed or\nmailed. Test checkout accepts card 4242 4242 4242 4242, any future expiry and any\nCVC. Never request real card data in chat. The reviewer cannot fund or spend a\nprepaid balance, create API keys or grants, or initiate physical fulfillment.\nNever invent paid, printed or mailed results; read the actual test order status.\n"
}