Send physical letters with Hermes Agent and FrankKi MCP

Give Hermes Agent a way to post the letter

A letter drafted in a chat still needs an envelope, postage and a trip into the postal system. FrankKi provides the physical-mail tools. Hermes Agent, the AI agent from Nous Research, supports remote MCP servers. That gives it a documented connection route for accessing FrankKi tools.

This guide uses the authenticated FrankKi account connection. The configuration follows the official documentation checked on September 13, 2026. We have not yet verified an end-to-end Hermes-to-FrankKi session. Treat the connection check below as a prerequisite before using it for real correspondence.

Connect Hermes Agent to FrankKi MCP

Start with a working Hermes installation and a FrankKi account set up for MCP access. The FrankKi MCP overview explains the service; the developer documentation covers account access and tools.

Merge this entry into ~/.hermes/config.yaml, preserving any existing servers. Hermes supports remote HTTP MCP connections and browser-based OAuth authentication.

mcp_servers:
  frankki:
    url: "https://mcp.frankki.app"
    auth: oauth

Complete the browser sign-in with hermes mcp login frankki, run hermes mcp test frankki to check the connection, then start hermes chat. In an existing session, use /reload-mcp. Review the requested account permissions during sign-in. This workflow uses human approval for each letter.

The configuration keys are documented in the Hermes MCP reference. See the Hermes MCP guide for login and tool discovery.

Check the connection before drafting

Use the FrankKi connection to check account access. Show which letter tools are available. Do not create a draft, request payment or send anything.

A useful result names the connected tools and reports any account setup still required. If Hermes cannot see them, resolve authentication or tool filtering first. A successful login alone does not prove that the letter workflow is ready.

Turn a supplier question into a reviewed letter

Suppose a supplier has not answered a question about an order. Give Hermes the relevant facts and ask for a short written request. Include the verified postal address, your return address and the order reference. Ask it to leave missing facts blank instead of guessing.

Prepare a letter asking the supplier for an update on order [reference]. Use the sender and recipient addresses I provide. Keep the request factual. Show me the finished page preview and fetch a current shipping quote for the recipient country. Wait for my approval before sending.

FrankKi exposes separate tools for creating the draft, previewing it and obtaining a shipping quote. Check the rendered pages, including addresses and attachments. A polished paragraph in chat does not tell you whether the printed page has the correct recipient.

Use the returned quote to choose an available delivery method. Price and availability depend on the destination and the letter. If you edit the content, address or attachments, review the updated preview and quote before approving.

Keep approval tied to this letter

A remembered preference for concise writing is useful. An old instruction to handle correspondence is not a decision about the cost and contents of a new letter. For this workflow, approve the specific letter through FrankKi after reviewing it. Ask Hermes to report the resulting order status rather than declaring success from a draft or tool request.

For recurring account use, FrankKi uses a prepaid wallet. Consult business pricing for the account model and use the live quote for the actual send. Keep agent or model costs separate from letter charges.

What to check when the workflow stops

If Hermes reports an HTML preflight response, its reference documents skip_preflight: true under the server entry. FrankKi serves an HTML landing page on GET at the MCP host, so this may be relevant. That compatibility option has not been tested here.

If tools are missing, check the active Hermes profile, the server entry and any include or exclude filters. If FrankKi rejects a call, read the returned account or permission requirement before retrying. A timeout after a send-related request needs an order-status check before another submission, so you do not request a duplicate letter.

For a general explanation of the service, see MCP servers for physical mail compared. This Hermes guide focuses on connecting your agent and reviewing its first letter.

Using OpenClaw? Read the physical-mail setup guide.

Photo: Kampus Production / Pexels.