---
name: send-letter
description: Send a physical letter through PostBridge's postal execution layer — quoting postage, validating addresses, and dispatching via print-and-mail providers. Use when the user asks to mail, post, or send a physical letter or document, or asks for a postage quote.
license: MIT
metadata:
  author: postbridge
  version: "0.1"
---

# Send a letter

PostBridge turns a PDF (or generated document) into a physically mailed letter.
All operations run through the `postbridge` MCP server and spend from the
authenticated workspace wallet.

## Workflow

1. **Know the addresses.** Collect recipient and sender addresses. Format rules
   are country-specific — see `references/address-formats.md`. For countries
   outside the reference set, ask the user to confirm the layout rather than
   guessing.
2. **Quote first.** Call `get_quote` with the destination country, page count,
   and mail class before any send. Present the price to the user.
3. **Confirm before spending.** `send_letter` charges the workspace wallet and
   triggers a physical mailpiece. NEVER call `send_letter` without explicit
   user confirmation of: recipient address, document content, service/class,
   and quoted price. Treat silence as "no".
4. **Send.** Call `send_letter` with the document and addresses. Capture the
   returned letter id and tracking number; report both to the user.
5. **After send.** Offer tracking (`track_letter`) and proof (`get_proof`) —
   see the `track-and-proof` skill.

## Rules

- The MCP session requires the workspace's SaaS API & MCP key (subscription-backed).
  If calls fail with an authorization error, direct the user to Settings → API & MCP.
- Never embed or log the API key. Never call wallet-mutating tools without the
  confirmation step above.
- Addresses are passed as structured fields, not free text blobs. When parsing
  free-form text, produce explicit lines and have the user confirm them.
- Certified/registered options and return receipts, where offered, must be
  surfaced with their price delta before selection.