Reference

USMail.ai documentation

What these docs are

This set is how you connect. It is not a brochure. It is not a public API catalog. It is not a list of hostnames.

You read these pages when you already want print-to-mail and you are ready to put the account in an agent environment. The pages tell you what is live, what is planned, and what we will not publish on www.

Product pages tell you what production does. Docs tell you how an agent prepares a job and how you still spend the meter. MCP does not create a second factory. Portal jobs and agent jobs share print, insert, postage, and the handoff to USPS.

Two seats stay separate. You own the account. You fund the meter. You approve. The agent logs in from env, prepares the job, and stops. Do not collapse those seats.

You may be the person who configures the agent. You may be the person who owns the USMail.ai account. You may be both. The account holder still approves on the app. The person who writes the agent still puts credentials in env, not in the prompt.

Docs vs product pages

Two kinds of pages. Do not mix them.

• /docs and the four MCP pages under it are operator docs. Chrome is the docs shell. Tone is how, not why.
• /mcp is the marketing lander. Use it when you explain MCP to a person who has not connected yet.
• How it works, Features, Print & mail, and Certified Mail describe production. Cutoffs, tracing, and proof options live there.

When the question is login, meter, session token, or tools, stay in docs. When the question is the factory, leave docs. Docs link the product pages. They do not restate them.

Recurring files and lists still use the same path. You still approve each job. We do not auto-mail next month because last month ran. Statements & invoices →

Start here

• MCP overview

  Status, flow, and limits. Why a human still confirms.

• Getting started

  Six operator steps. What empty meter and auth fail look like.

• Auth & billing

  Account, meter, session token. Planned keys. Link to Security.

• Tools reference

  English capabilities. Mixed lists. Live names after login. Persist does not print.

Read them in that order the first time. After that, jump. Overview is status. Getting started is the path. Auth is the secret and the spend. Tools is what the agent can call in English.

Human approve

Physical mail cannot be unsent once we produce it. The meter spends real postage. Certified Mail is proof when you select it. An agent can assemble files, options, and a proof and still be wrong about the recipient, the class, or the date.

Until you confirm on the app, the job is a draft. After you confirm, we print, insert, apply postage, and deliver the pieces to USPS. That confirm is the spend.

Agents prepare jobs. They do not run card deposits. They do not approve production mail. Why that gate exists: MCP overview.

What these pages will not publish

We do not publish MCP hostnames here. We do not publish add commands. Do not invent hostnames or add commands. Connection details come with access on the app.

We do not list mill tool names. We do not invent public aliases for tools. English capabilities live on Tools reference. The live list is on the MCP server after login.

We do not publish unit prices. Production mail is not free. Billing is the prepaid meter. Auth & billing →

Keep the password in env. Never in the prompt. Never in a public repo. If login fails, log in again. If the meter cannot cover the job, fund it in the app, then approve. Those failures are on Getting started.

Account practices: Security. Stuck: Contact. Also: MCP lander · How it works · Print & mail · Certified

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