1
Copy the Mermail MCP URL
Streamable HTTP only (POST), not SSE. Interactive Hermes uses OAuth — do not add x-api-key. Requires a standard Hermes install (MCP extras included).
MCP endpoint
https://console.mermail.app/mcpHERMES
Give Hermes
a real inbox.
Add Mermail as a Streamable HTTP MCP server in Hermes Agent. OAuth opens a browser, then the agent can list mailboxes, read mail, and finish paid workflows in chat.
Why Hermes
Built for the agent you already use.
Mermail gives Hermes a dedicated inbox and payment layer so verification, checkout, and receipts stay in the same loop.
Hosted MCP over Streamable HTTP
OAuth via auth: oauth — no x-api-key in the interactive path
hermes mcp login mermail from a fresh terminal
CLI still available for batch JSON and JMESPath jobs
Three steps to connect.
2
Add Mermail to ~/.hermes/config.yaml
Paste under mcp_servers (merge if that key already exists). Then run hermes mcp login mermail from a new terminal — in-session reload only waits 30s, which is too short for OAuth.
Config
mcp_servers:
mermail:
url: "https://console.mermail.app/mcp"
auth: oauth
# Then, from a fresh terminal:
hermes mcp login mermail3
Authorize, then use a tool
Complete Google login on console.mermail.app, pick a workspace, then start hermes chat or type /reload-mcp. Tokens are cached at ~/.hermes/mcp-tokens/.
Verify
hermes chat
# or, in an existing session: /reload-mcp
Ask: "List my Mermail mailboxes" (tool: list_mailboxes)Questions, answered.
Auth, transports, and how to confirm the connection before you trust the agent.
Do I need an API key in Hermes?+
Not for interactive chat. Use auth: oauth and hermes mcp login mermail. For jobs or headless hosts, drop auth: oauth and set headers.x-api-key to ${MERMAIL_API_KEY} in ~/.hermes/.env.
Should Hermes use MCP or the CLI?+
Use MCP for interactive agent loops. Keep mermail-cli for batch JSON and JMESPath. Destructive CLI commands need --yes when non-interactive.
How do I know Mermail is connected?+
Ask the agent to list your Mermail mailboxes. A healthy connection exposes the hosted MCP tools, including list_mailboxes.
Where is the live walkthrough?+
The Agents page Hermes tab walks through MCP, CLI, and Skills side by side. CLI reference: https://docs.mermail.app/ai/cli.
See all integrations
Integration indexClaude
Install the Mermail plugin so Claude can provision an inbox, read verification mail, and finish paid workflows without leaving the terminal.
ChatGPTAdd Mermail as a custom ChatGPT connector. Streamable HTTP plus OAuth — no API key in the connector. Then ChatGPT can list mailboxes, read mail, and finish paid workflows.
CodexInstall the Mermail plugin so Codex maps MERMAIL_API_KEY into MCP, loads 11 skills, and can list mailboxes, draft replies, and complete checkout.
CursorInstall the hosted MCP server with OAuth. Cursor discovers Protected Resource Metadata after a 401, then your agent can read mail and act on payments inside the IDE.
OpenClawPoint OpenClaw at hosted MCP with Streamable HTTP and x-api-key. Probe the connection, then let the agent manage inboxes and payment receipts.