Send a letter from OpenCode.

Add paperplane to opencode.json and it can quote and send a real USPS letter — no account required, free sandbox mode included.

Free to preview — see the exact PDF before you pay. Sending starts at $1.99, no account required.

Set it up in OpenCode

Step 1

Add to opencode.json

The only client here using "type": "remote".

{
  "mcp": {
    "paperplane": { "type": "remote", "url": "https://sendpaperplane.com/api/mcp", "enabled": true }
  }
}

Try it: free, nothing mailed

Tell your agent:

Using the paperplane tools, quote a 1-page certified letter to Property LLC, 1 Main St, Richmond VA 23220, then send it in sandbox mode.

Not on OpenCode? Any surface works.

The same three calls from the CLI, any MCP client or plain REST. Sandbox is free and mails nothing.

Send a letter

{
  "mcp": {
    "paperplane": { "type": "remote", "url": "https://sendpaperplane.com/api/mcp", "enabled": true }
  }
}

All agents · API docs

Common questions

Why does OpenCode’s config say "type": "remote"?

OpenCode is the only client here using "remote" rather than "http" or "streamableHttp" — copy the exact block above rather than another client’s type field.

What tools does OpenCode get?

quote_letter, send_letter, and get_letter_status for mailing, plus buy_credits for pre-funding sends. Postcards are live (from $1.99) via the REST API’s format field, though not yet an MCP tool argument.

How much does sending cost?

Letters start at $1.99 for First-Class; Certified Mail starts at $12.99. Sandbox mode is free.