Agents should be able to help with physical mail without skipping user control. That is the design principle behind PostalForm’s agent guide and MCP workflow.

Instead of making an assistant immediately print and mail something, PostalForm lets an agent create a reviewable draft. The user can inspect the generated PDF, addresses, service level, and price before payment.

The safer default

For chat-style assistants and most user-facing workflows, the right default is:

Create a draft
Render a PDF preview
Validate sender and recipient details
Return a checkout URL or checkout session
Let the user approve payment
Track fulfillment after checkout

That split matters because physical mail has real-world consequences. A typo in an address, an accidental duplicate, or a letter sent before review is harder to unwind than a normal software action.

What the agent surface supports

PostalForm’s agent-facing docs describe multiple paths:

  • MCP tools for creating draft mail orders.
  • Hosted checkout when a human should review and pay.
  • Machine-order APIs for autonomous runtimes with explicit approval and spend controls.
  • Fulfillment status tools so the agent can report what happened after payment.

The important product boundary is that draft creation is not the same as mailing. PostalForm keeps the irreversible step behind checkout or a paid machine-payment retry.

Source note

This post is based on the public PostalForm Agents Guide and PostalForm MCP developer docs.