Send mail from agents and apps.

Quote, confirm, send and track real USPS mail over MCP, REST or CLI. No account, no API key. The sandbox is free.

Connect your agentRead the docs

claude mcp add --transport http paperplane https://sendpaperplane.com/api/mcp

Using the paperplane tools, quote a 1-page certified letter to Property LLC, 1 Main St, Richmond VA 23220, from Alex Rivera, 12 Grove Ave, Richmond VA 23221, then send it in sandbox mode.

The benchmark, replayed

Claims about being agent-ready are cheap; transcripts aren't. This is the real captured sandbox run — quote → send → track in 3 calls, zero schema retries — including the part where a replayed request and a reused confirmation token both fail to double-send. Full write-up: agent benchmark.

POST /v1/quotes
{
  "mail_class": "certified",
  "page_count": 1,
  "to": {
    "name": "Property LLC",
    "line1": "1 Main St",
    "city": "Richmond",
    "state": "VA",
    "zip": "23220"
  },
  "text": "Formal demand for return of my security deposit within 14 days of this notice."
}

{
  "status": "ok",
  "total_cents": 1299,
  "total": "$12.99",
  "breakdown": [
    {
      "id": "certified_mail_letter_1_page",
      "label": "Certified Mail letter, 1 page",
      "amount_cents": 1299
    }
  ],
  "confirmation_token": "ppq_eyJ2IjoxLCJqdGkiOiJhNDBlZjFiMzFhZDMxYjMx…",
  "expires_in_minutes": 30,
  "next": [
    "POST /v1/orders with this confirmation_token and the same recipient, content, and options."
  ]
}

POST /v1/orders
Idempotency-Key: bench-2026-08-25-a
{
  "mail_class": "certified",
  "sandbox": true,
  "confirmation_token": "ppq_eyJ2IjoxLCJqdGkiOiJhNDBlZjFiMzFhZDMxYjMx…",
  "to": {
    "name": "Property LLC",
    "line1": "1 Main St",
    "city": "Richmond",
    "state": "VA",
    "zip": "23220"
  },
  "from": {
    "name": "Alex Rivera",
    "line1": "12 Grove Ave",
    "city": "Richmond",
    "state": "VA",
    "zip": "23221"
  },
  "text": "Formal demand for return of my security deposit within 14 days of this notice."
}

{
  "status": "ok",
  "order": {
    "id": "ord_test_f5ca66ace638fdc1",
    "status": "submitted",
    "sandbox": true,
    "price_cents": 1299,
    "tracking_number": "9400MOCK00000001"
  },
  "corrected_to": {
    "name": "Property LLC",
    "line1": "1 MAIN ST",
    "city": "RICHMOND",
    "state": "VA",
    "zip": "23220"
  },
  "capability": {
    "cancel_token": "…",
    "review_token": "…"
  }
}

GET /v1/orders/ord_test_f5ca66ace638fdc1

{
  "status": "ok",
  "order": {
    "status": "submitted",
    "tracking_number": "9400MOCK00000001",
    "…": "…"
  }
}

POST /v1/orders
Idempotency-Key: bench-2026-08-25-a

{
  "status": "ok",
  "replayed": true,
  "order": {
    "id": "ord_test_f5ca66ace638fdc1",
    "…": "…"
  }
}

POST /v1/orders

POST /v1/orders

Every failure that transcript beat could have ended on, rendered the same way: the full error contract, visually.

Services

4 flagship formats shown; full price list

Plans

Resources

Agent card preview

{
  "name": "paperplane",
  "interfaces": {
    "mcp": { "transport": "streamable-http", "url": "https://sendpaperplane.com/api/mcp" },
    "rest": { "openapi": "https://sendpaperplane.com/v1/openapi.json" }
  },
  "pricing": {
    "model": "per-transaction",
    "currency": "USD",
    "items": [
      { "sku": "first_class", "price": 0.99, "unit": "letter (1 page B&W)" },
      { "sku": "certified", "price": 12.99, "unit": "letter" }
    ]
  },
  "authentication": { "required": false, "scheme": "bearer" }
}

Supported payment methods

How agents pay

1. 01

   Get a quote

   POST /v1/quotes (or the quote_letter MCP tool) prices any letter, free. Returns a confirmation_token bound to the exact recipient, content, class, and price.

2. 02

   Confirm and pay

   POST /v1/orders with that token returns a paperplane payment link for the human to approve (or, for an agent with its own wallet, settles USDC over x402 once that lane is live — see payment methods above). A send is never the first call.

3. 03

   Track the letter

   GET /v1/orders/:id (or get_letter_status) reports the lifecycle from screening to delivered.

Sandbox: every path below (MCP, CLI, REST) supports sandbox: true (or --sandbox) to run the entire flow — rendering, screening, simulated fulfillment with tracking — instantly and free. An agent's first call can succeed before any human has signed up for anything.

Developer console

Sign in to see your letters in one place — live status, tracking, and receipts — even though sending stays keyless.

Sign in

Error contract

Every error is structured for agents: { status, code, reason, next: ["what to do"] }. Address problems return the USPS-corrected candidate. Nothing requires reading HTML or guessing.

Content rules

Every letter is screened before printing (policy). Lawful demand letters and firm legal language are explicitly allowed; threats, fraud, and impersonation are refused and the payment released.

Questions before you integrate

npx paperplane send letter.pdf \
  --to "Maria Alvarez, 1 Main St, Richmond VA 23220" \
  --from "Alex Rivera, 12 Grove Ave, Richmond VA 23221" \
  --sandbox