For AI agents

Let your agent run your toll booth.

InboxToll has an MCP server. Add it to your AI agent and say things like “set up InboxToll at $1”, “what's waiting at the toll booth?”, or “let everyone from acme.com through”.

MCP server URL

https://inboxtoll.com/mcp

Your agent will open an InboxToll page where you sign in and click Allow. No API keys to copy.

Claude

Settings → Connectors → Add custom connector.
Name: InboxToll, URL: https://inboxtoll.com/mcp → Add, then Connect and click Allow.

Claude Code: claude mcp add --transport http inboxtoll https://inboxtoll.com/mcp, then run /mcp to sign in.

ChatGPT

Settings → Apps & Connectors → Create (developer mode may need to be on).
MCP server URL: https://inboxtoll.com/mcp, authentication: OAuth → create, then sign in and Allow.

Cursor, Windsurf, and other MCP clients

Add a remote (Streamable HTTP) MCP server with this config, then complete the sign-in when prompted:

{
  "mcpServers": {
    "inboxtoll": { "url": "https://inboxtoll.com/mcp" }
  }
}

What your agent can and can't do

✓ Check setup and status, change your price, auto-reply text, and filters
✓ List, release, trash, whitelist, or block held messages
✓ Manage your whitelist and block list, report earnings and activity
✕ Read the content of your email, send email, or change where your money goes
✕ Connect Gmail/Outlook or verify your identity with Stripe. Those two steps need you, so your agent will send you a link.

Disconnect an agent anytime in Settings → AI agents.

Paying a toll from an AI agent (HTTP 402)

If your agent emails an InboxToll user it doesn't know, the message is held and the automatic reply carries two headers: X-InboxToll-Pay-URL and X-InboxToll-Price. Your agent can pay without a browser:

Request the Pay URL (GET or POST). An unpaid message returns 402 Payment Required with a WWW-Authenticate: Payment challenge (the Machine Payments Protocol, settled by Stripe) and a JSON body with the amount.
Pay with an MPP client such as mppx, using a card through a Stripe Shared Payment Token. It retries the same URL with Authorization: Payment ….
Done: a 200 receipt, and the message lands in the recipient's inbox marked Paid. Retrying never charges twice.

$ curl -i https://inboxtoll.com/api/v1/pay/pm_…

HTTP/1.1 402 Payment Required
WWW-Authenticate: Payment method="stripe", intent="charge", request="…"

{ "amount": "2.37", "currency": "USD", "recipient": { "handle": "griffin" } }

Recipients set a separate price for agents. Look one up at /api/v1/u/{handle}. Machine-readable details: /.well-known/inboxtoll.json and /llms.txt. Paying guarantees delivery, not a reply. USDC payments (x402 and MPP stablecoins) are coming next.