Agent integrations
Official PostalForm agent integrations
PostalForm provides one documented path from agent input to a printable document and reviewable mailing. Start with https://postalform.com/mcp for hosted-checkout drafts. Use the machine form reference to discover each published form's fields, attachment requirements and recipient rules.
Published Oct 15, 2026
How it works
Upload your PDF
Drag and drop your document or upload from phone.
Add addresses
Enter sender and recipient addresses with validation.
Checkout
We print and mail it via USPS with your chosen options.
Which integration should an agent use?
PostalForm supports unpaid draft preparation through MCP and separate machine-payment flows through MPP and x402. Use MCP when a person should inspect the PDF and complete hosted checkout. Choose a payment integration only when the owner has authorized the mailing and spending, and the client supports the required payment credentials.
Protocol and capability map
| Capability | Endpoint or discovery | Guide | Important boundary |
|---|---|---|---|
| Hosted MCP draft tools | /mcp |
Agent skill | Creates unpaid drafts for PDF, letter and supported form workflows |
| MCP server metadata | /.well-known/mcp/server.json and /.well-known/mcp/server-card.json |
Developer guide | Read live tool schemas before invoking |
| ACP checkout over MCP | /acp/mcp; /.well-known/acp.json |
ACP guide | Checkout and token compatibility depend on the client |
| UCP checkout | /ucp/mcp; /.well-known/ucp |
UCP guide | PDF-based checkouts with Loqate Address IDs; use /mcp for manual addresses, letter text and forms |
| MPP document mail | /api/machine/mpp/orders |
MPP mail | Answer the payment challenge only with owner authorization |
| x402 document mail | /api/machine/orders; /.well-known/x402 |
Machine guide | Preserve request ID and payload when retrying a challenge |
| Form catalog and schemas | /api/machine/forms; /api/machine/forms/{slug}/schema |
HTML and Markdown form references | Published single-mailpiece workflows only |
| Postcards | Browser /postcards; machine order endpoints |
Postcard guide | Two-page PDF and exact bleed canvas for custom artwork |
| Bulk mail | Machine order endpoints with bulk |
Bulk mail guide | Exactly one of CSV content or JSON recipients; review the whole campaign total |
| Flower letters | /api/machine/mpp/flower-letters |
Flower letter guide | Separate product and eligibility checks |
| Parcel label PDFs | /api/machine/mpp/shipping-labels |
Shipping label guide | PostalForm returns a label; the user packages and tenders the parcel |
Download the integration kit
These files are official examples generated or copied from PostalForm's integration sources during the website build. The Python adapters expose discovery, unpaid drafts and status lookup. They fetch the server's current input schemas and do not expose payment tools.
| File | Purpose |
|---|---|
| Integration setup instructions | Installation, client configuration and behavior |
| Installable SKILL.md | Narrow prepare-review-checkout workflow |
| Prompt templates | PDF, guided-form, validation and status prompts |
| Remote MCP configuration | HTTP-capable clients |
| Claude Desktop configuration | Local stdio configuration; replace the absolute paths |
| Local stdio bridge | Uses the official MCP Python SDK |
| Shared Python client | Tool allowlist, live schemas and single-attempt calls |
| Python requirements | Core SDK dependency |
| LangChain tools | Async tools for schema discovery and draft calls |
| CrewAI tools | Sync and async BaseTool adapters |
| OpenAI Actions schema | Form discovery and mailing validation; no paid-order operation |
The Actions schema is derived from the same OpenAPI definitions as the live machine API. Validation transmits the submitted document and addresses to PostalForm and is marked consequential for client review. Use the MCP draft tools when a human needs a checkout link.
Review and authorization
Fetch the live tool schema, collect the user's confirmed document and address information, create an unpaid draft, and show the PDF preview, recipient, service and total. Hosted checkout lets the owner complete payment. An autonomous integration must enforce the owner's mailing and spending authorization separately; a valid schema or payment challenge does not supply that authorization.
Do not silently retry a draft creation after a timeout. An uncertain result can already exist. Check the returned order ID and status when available before creating another. The kit preserves MCP error flags and structured results so a caller can distinguish tool failures from successful drafts.
Simple pricing
Base fee plus per-page printing. Postage included. See pricing for details.
PostalForm U.S. First-Class mailing for one black-and-white document page plus the address page starts at $3.40. Certified Mail adds $8.00; Electronic Return Receipt adds $3.00 to Certified Mail. Your document, print choices, destination, and delivery options determine the checkout total. See the full pricing matrix.
Which mailing option and proof should you choose?
PostalForm offers U.S. letter mailing with different delivery and proof options. First-Class suits routine correspondence; Certified Mail adds mailing and delivery records, and Electronic Return Receipt adds a downloadable signature record. Expedited delivery prioritizes speed. Review the destination, estimated dates, total price, and required proof before paying.
| Mailing option | Delivery speed | Proof | Use when | Avoid when |
|---|---|---|---|---|
| USPS First-Class Mail | First-Class Mail delivery estimate shown before payment. | Available processing scans; no recipient signature or Certified Mail receipt. | Routine letters when a signed delivery record is unnecessary. | Your instructions require Certified Mail, a signature, or a deadline this estimate cannot meet. |
| Certified Mail | First-Class delivery speed; certification does not make delivery faster. | USPS mailing and delivery/attempt tracking; no Electronic Return Receipt unless added. | You need a recorded mailing and delivery or attempted-delivery status. | You need a downloadable signature record or faster delivery. |
| Certified Mail + Electronic Return Receipt | First-Class delivery speed; signature collection may require redelivery or pickup. | Certified Mail records plus a downloadable USPS signature record when available. | Your instructions call for Certified Mail with Return Receipt or you need the signature record. | Your recipient requires an original enclosure, personal service, or another submission method. |
| Expedited / Express with signature | Faster estimated delivery range shown at checkout; production cutoff and destination apply. | Carrier tracking and signature option; this is separate from Certified Mail and ERR. | Speed and signature matter and checkout offers the service for your destination. | A rule specifically requires Certified Mail or the displayed estimate misses your deadline. |
Availability and delivery estimates depend on the document and destination. Mailing proof does not establish that a recipient accepted a filing or that legal service requirements were met. Delivery estimates · Full pricing
Why PostalForm
Delivery options
First Class or Expedited with optional Certified Mail.
Address validation
Reduce returned mail and delivery errors.
Fast checkout
Upload once and mail in minutes.
Ready to send it?
Upload your document and we will print and mail it.