AgentMail Skill for Hermes Agent: Give Your AI Its Own Email Inbox

The AgentMail skill gives a Hermes Agent its own email address and inbox, separate from any human account. You would use this when the agent needs to send or receive email autonomously: signing up for services, communicating with other agents, or reaching out to humans. It is an optional skill installed on demand, not a tool for reading your personal Gmail or Outlook.

What it does

AgentMail provides 11 tools through an MCP server that let the agent manage its own email identity. The agent can create and delete inboxes, send and receive messages, reply to and forward emails, manage threads, and download attachments. Each inbox gets a real email address at the @agentmail.to domain (or a custom domain on paid plans). The agent owns the inbox entirely; you do not expose your own email account.

Before you start

You need an AgentMail API key. Sign up at the AgentMail console (free tier gives you 3 inboxes and 3,000 emails per month; paid plans start at $20/month). The API key starts with am_.

The MCP server requires Node.js 18 or later. The mcp Python package must also be installed: pip install mcp. The skill runs on Linux, macOS, and Windows.

Setup

1. Get an API key

Go to the AgentMail console, create an account, and generate an API key.

2. Configure the MCP server

Add the following block to ~/.hermes/config.yaml. Paste your actual key directly in the file; MCP environment variables are not expanded from a .env file.

mcp_servers:
  agentmail:
    command: "npx"
    args: ["-y", "agentmail-mcp"]
    env:
      AGENTMAIL_API_KEY: "am_your_key_here"

3. Restart Hermes

hermes

All 11 AgentMail tools are now available automatically.

Available tools (via MCP)

Tool	Description
list_inboxes	List all agent inboxes
get_inbox	Get details of a specific inbox
create_inbox	Create a new inbox (gets a real email address)
delete_inbox	Delete an inbox
list_threads	List email threads in an inbox
get_thread	Get a specific email thread
send_message	Send a new email
reply_to_message	Reply to an existing email
forward_message	Forward an email
update_message	Update message labels/status
get_attachment	Download an email attachment

Procedure

Create an inbox and send an email

1. Create a dedicated inbox using create_inbox with a username (e.g., hermes-agent). The agent gets the address hermes-agent@agentmail.to.
2. Send an email using send_message with the inbox_id, to, subject, and text.
3. Check for replies by using list_threads to see incoming conversations and get_thread to read a specific thread.

Check incoming email

1. Use list_inboxes to find your inbox ID.
2. Use list_threads with the inbox ID to see conversations.
3. Use get_thread to read a thread and its messages.

Reply to an email

1. Get the thread with get_thread.
2. Use reply_to_message with the message ID and your reply text.

Example workflows

Sign up for a service:

1. create_inbox (username: "signup-bot")
2. Use the inbox address to register on the service
3. list_threads to check for verification email
4. get_thread to read the verification code

Agent-to-human outreach:

1. create_inbox (username: "hermes-outreach")
2. send_message (to: user@example.com, subject: "Hello", text: "...")
3. list_threads to check for replies

When not to use it

This skill is not for reading your personal email. If you need the agent to access your Gmail or other personal accounts, use the himalaya or Gmail skills instead. AgentMail gives the agent its own identity and inbox, separate from yours.

Limits and gotchas

• The free tier is limited to 3 inboxes and 3,000 emails per month.
• Emails come from the @agentmail.to domain on the free tier. Custom domains are available on paid plans.
• Node.js 18 or later is required for the MCP server (npx -y agentmail-mcp).
• The mcp Python package must be installed: pip install mcp.
• Real-time inbound email via webhooks requires a public server. For personal use, poll with list_threads on a cronjob instead.

Verification

After setup, test with:

hermes --toolsets mcp -q "Create an AgentMail inbox called test-agent and tell me its email address"

You should see the new inbox address returned.

References

• AgentMail docs: https://docs.agentmail.to/
• AgentMail console: https://console.agentmail.to
• AgentMail MCP repo: https://github.com/agentmail-to/agentmail-mcp
• Pricing: https://www.agentmail.to/pricing