Pony in Grok.
Add Mail by Pony to Grok. Grok writes the letter, Pony prints it and mails it through USPS.
Open Grok connectors
Go to grok.com/connectors, choose New Connector, then Custom.
Paste the server URL
Name it Mail by Pony, paste this URL and add the connector.
https://www.mailbypony.com/mcp/signinSign in to Pony
Grok opens Mail by Pony. Sign in, or create an account, and approve the connection. Never paste a password or code into the chat.
Ask Grok for a letter
Start a new chat with the Mail by Pony connector turned on and try:
Use Mail by Pony to write a thank-you letter to my grandmother and show me the proof.
What happens next
- Grok saves the letter as a draft on Pony and asks for the sender and recipient addresses in chat.
- Before sending, Grok shows the exact printed pages, the recipient and the price.
- When you say send, Grok gives you a payment link. Paying sends the letter. Sending often? Add money to your balance and allow Grok in Account → Credits.
- Order status shows what has happened. “Mailed” means handed to USPS.
Questions
Can Grok send real mail?
Yes, with the Mail by Pony connector. Grok writes and edits the letter, shows you the exact printed pages and gives you a payment link. Paying sends the letter: Pony prints it, puts it in an envelope and hands it to USPS.
Do I need a Mail by Pony account?
Yes. When you add the connector, Grok sends you to Mail by Pony to sign in or create an account and approve the connection.
I use Grok Business. Why can’t I add it?
On Grok Business and Enterprise, a team admin adds custom connectors first, in the xAI console under Grok Business → Connectors. Ask your admin to add https://www.mailbypony.com/mcp/signin.
Where can Pony mail letters?
To US addresses, through USPS. Standard letters are not tracked or certified.