---
title: PostalForm agent skill
description: Read this file before using PostalForm from an AI assistant, MCP client, coding agent, or autonomous runtime.
seotitle: PostalForm MCP agent skill
seo-description: Agent-ready setup instructions for using PostalForm MCP in ChatGPT, Gemini, Claude, Codex, and other MCP-capable clients to send real postal mail.
group: resources
indexable: true
nav: false
schema: webpage
eyebrow: Agent skill
published: 2026-05-30
updated: 2026-05-31
path: /skill
---
# PostalForm agent skill

Read this file before using PostalForm from an AI assistant, MCP client, coding agent, or autonomous runtime.

## Quick setup
- Remote MCP endpoint: `https://postalform.com/mcp`
- Transport: streamable HTTP
- Authentication: none required today for the hosted MCP endpoint
- A2A Agent Card: `https://postalform.com/.well-known/agent-card.json`
- MCP manifest: `https://postalform.com/.well-known/mcp.json`
- MCP Server Card: `https://postalform.com/.well-known/mcp/server-card.json`
- MCP Registry server manifest: `https://postalform.com/.well-known/mcp/server.json`
- OpenAPI: `https://postalform.com/openapi.json`
- Full developer docs: `https://postalform.com/developers`
- Autonomous payment guide: `https://postalform.com/agents`

If your client accepts a remote MCP URL, add `https://postalform.com/mcp` as a streamable HTTP MCP server named `postalform`.

## Works with
PostalForm is designed for MCP-capable clients and runtimes including ChatGPT custom connectors or OpenAI Responses API MCP tools, Gemini SDKs, Gemini CLI, Claude, Claude Code, Codex, Cursor, Windsurf, Cline, Replit, OpenClaw, Hermes, n8n, LangChain, and other clients that can connect to a remote streamable HTTP MCP endpoint.

For ChatGPT or OpenAI API flows, configure a remote MCP tool with `server_url` set to `https://postalform.com/mcp`. Require approval for tool calls that send document contents, addresses, or payment-related data.

For Gemini CLI, add PostalForm as an HTTP MCP server:

```bash
gemini mcp add --transport http postalform https://postalform.com/mcp
```

For Gemini SDK integrations, connect to the same MCP endpoint with an MCP client session and pass the session tools to the Gemini SDK's MCP/tool-calling integration.

## Tool choice
Use these tools first when a human should review and pay:

- `postalform.create_letter_order_draft` for a plain letter that PostalForm renders into a printable PDF.
- `postalform.create_order_draft` for an uploaded PDF or a PDF file URL.
- `postalform.list_forms`, `postalform.get_form_schema`, and `postalform.create_form_order_draft` for supported form workflows.
- `postalform.search_addresses` when the user wants autocomplete-backed address validation.
- `postalform.get_order_status` after checkout starts or payment completes.

Use `postalform.create_machine_order` only when the owner explicitly authorized autonomous payment and the runtime has a spend limit. The first call returns an MPP or x402 payment challenge. Retry the same request with the payment credential after the payment client answers the challenge.

## Payment guidance
- Default for ChatGPT, Gemini, Claude, and web-chat style clients: create a draft and return `checkout_url` or `checkout_session`.
- Default for autonomous coding agents with explicit approval: validate or create a machine order, show the preview and price, then answer the MPP or x402 challenge.
- Never send raw card details to PostalForm. Machine payment paths use MPP, x402, hosted checkout, or Stripe Shared Payment Tokens where applicable.

## Mailing rules
- PostalForm supports specific destination countries. Validate or quote the order before promising delivery.
- Certified Mail is only available for qualifying U.S. First Class mail.
- Express, Fast, postcard, international, and provider-specific options vary by destination, size, address, and provider eligibility.
- Do not use PostalForm for physical originals, checks, keys, ID cards, packages, notarization, process serving, legal advice, or guaranteed delivery by a specific date.

## Best prompt for a user
Ask the user for the document or letter text, sender address, recipient address, preferred mailing option, and whether they want to review and pay in hosted checkout. Then create a PostalForm draft and return the checkout URL.

## Minimal letter example
Call `postalform.create_letter_order_draft` with:

```json
{
  "letter": {
    "title": "Payment demand",
    "body": "Hello,\n\nThis is the letter body.\n\nSincerely,\nSender Example",
    "signature": "Sender Example"
  },
  "sender_name": "Sender Example",
  "sender_address_type": "Manual",
  "sender_address_manual": {
    "line1": "123 Sender St",
    "city": "Springfield",
    "state": "IL",
    "zip": "62701"
  },
  "recipient_name": "Recipient Example",
  "recipient_address_type": "Manual",
  "recipient_address_manual": {
    "line1": "456 Recipient Ave",
    "city": "Springfield",
    "state": "IL",
    "zip": "62701"
  }
}
```

Return the resulting `checkout_url` to the user for final review and payment.

## Machine-readable references
- `https://postalform.com/llms.txt`
- `https://postalform.com/llms-full.txt`
- `https://postalform.com/ai.md`
- `https://postalform.com/developers.md`
- `https://postalform.com/agents.md`
- `https://postalform.com/pricing-calculator.md`