Before you start
Check 3 things.
You can send messages in Muse main chat.
You can sign in to the intended Mermail workspace.
You can create a project API key in Settings → API Keys.
META MUSE
Give Muse
its own inbox.
Paste a setup prompt, store a project API key in Secrets, and let Muse write a Mermail connector.
Why Muse
Built for the agent you already use.
Mermail gives Muse a mailbox it owns, so signups, vendor mail, and receipts stay off your Gmail.
A hosted @mermail.app address Muse owns
Verification codes land in Muse’s mailbox
Your Gmail stays off vendor lists
Muse Code OAuth when you need PayBox
Mermail Authentication docs
Success contract
Done when all 3 pass.
The Muse key is stored in Secrets, not chat.
Muse lists mailboxes with the Mermail API.
A test send from a hosted @mermail.app address reaches you.
Five steps to connect.
1
Send the setup prompt
Paste this in Muse main chat. Use Mermail’s API, not Gmail. Open Secrets for the key.
Prompt
Get yourself a Mermail email address.
Use the Mermail HTTP API at https://console.mermail.app/api/v1. Read https://docs.mermail.app first. Authenticate with the x-api-key header — never ask me to paste a key in this chat. Open the Secrets tab when you need it.
List existing mailboxes before creating one. Create a hosted @mermail.app mailbox only if none is suitable. Creating a mailbox costs 10 provision credits. Then tell me the address.2
Create a project API key
Create a key named Muse in Settings → API Keys and copy it once.
Open API Keys3
Paste the key in Secrets
Muse opens the Secrets tab. Paste the key there. Never paste a sk-proj- key into chat.
4
Approve the connection
Approve Mermail in the approval panel. A standing permission is optional.
5
Confirm with a test send
Muse lists mailboxes, creates a hosted address only if needed, then emails you.
Verify
Ask: "List my Mermail mailboxes, then send a short test to me at YOUR_EMAIL from the hosted address."Alternate path
Using Muse Code?
Connect Muse Code over MCP OAuth. This path unlocks PayBox. Secrets does not.
1
Add Mermail to Muse Code settings
Write this into ~/.config/muse/settings.json. schema_version must be 1.
Config
{
"schema_version": 1,
"mcp_servers": {
"mermail": {
"transport": "streamable_http",
"url": "https://console.mermail.app/mcp",
"enabled": true,
"mode": "required"
}
}
}2
Sign in with OAuth
Run login, pick the intended workspace, then return to the CLI.
Auth
muse mcp login mermail3
Verify, then optionally install skills
Open /mcp and run a read-only check. Muse Code also loads skills from ~/.agents/skills.
Verify
/mcp
Ask: "List my Mermail mailboxes" (tool: list_mailboxes)
npx --yes skills add Nudgen-Marketing/mermail-skills --skill '*' --global --yesWorking prompt
Prove the mailbox works.
Paste this after setup. Replace YOUR_EMAIL with an inbox you can check.
Prompt
Use your hosted Mermail mailbox for this chat. If none exists, list mailboxes first and create one only if needed. Send a short test to me at YOUR_EMAIL and report the From address. After I reply, check that thread and tell me what I wrote.Recipes
Copy a job into chat.
Paste any prompt into Muse main chat, or into a side chat for that job. Muse asks for approval where your permission settings require it.
Signups
Sign up as itself
Muse creates the account under its hosted address and reads its own verification codes.
Prompt
Create a hosted Mermail mailbox for this job if I do not already have one. Use it to sign up for the account I named, wait for the verification email, read the code, and finish signup. Tell me when the account is ready. Do not use my Gmail.What happens. The code lands in Muse’s mailbox, not yours.
Outreach
Get quotes
Vendor replies go to Muse, not your personal address.
Prompt
From your hosted Mermail mailbox, email five local moving companies for a quote on a two-bedroom apartment move on the date I gave you. Track every reply. When three have answered, compare price, date availability, and insurance, then recommend one.What happens. Each company stays in one thread history on Muse’s mailbox.
Outreach
List a sale
Buyers and dealers email Muse, not you.
Prompt
Reuse your hosted Mermail mailbox, or create one named car-sale if your plan allows another mailbox. Use that address as the contact email on my listing. Answer buyer questions from the details I gave you, screen out lowball offers under the floor I set, and bring me anyone ready to schedule a viewing.What happens. Your personal address never touches the listing or a dealer CRM.
Productivity
Forward, don’t connect
Keep Gmail disconnected. Muse works only from what you send it.
Prompt
I’ll forward you emails at your hosted Mermail address when I need help. For each one, tell me what it’s asking, what’s due and when, and draft what I should do. Don’t read anything I didn’t send you.What happens. Muse works only from forwarded mail. No Gmail access.
Errands
Chase a refund
The customer-service follow-up you’ve been putting off.
Prompt
I’m forwarding you my order confirmation. Email the store’s support address from your hosted Mermail mailbox, ask for a return label, and follow up every two days until they reply. Send me the label when it arrives.What happens. The back-and-forth lives in Muse’s mailbox until you need to act.
Productivity
One mailbox per side chat
Keep a long-running job on its own address when your plan allows it.
Prompt
For this side chat, create a hosted Mermail mailbox named wedding-vendors if my plan allows another mailbox. Otherwise reuse the existing hosted address and keep this work here. Use it for every vendor we contact. Once a week, send me a summary of open questions, deposits due, and who hasn’t replied.What happens. Vendor mail for that job stays out of your inbox and Muse’s other chats.
Productivity
CC Muse on a thread
Loop the agent in like a colleague.
Prompt
When someone CCs your hosted Mermail address on a thread, read the full history, work out what’s being asked of me, and message me a one-line summary with a suggested reply. Don’t reply on the thread unless I say so.What happens. Muse follows the thread without access to the rest of your mail.
Productivity
Alert sink
Promo mail goes to Muse, not you.
Prompt
Reuse your hosted Mermail mailbox, or create one named deals if your plan allows another mailbox. Use it to sign up for price alerts on the three items on my wishlist. Only message me when one drops more than 20%.What happens. Your inbox stays clean; Muse filters.
Is there an official Mermail connector for Muse?
No. Muse writes a connector from the Mermail API. Setup takes a few minutes and needs no code.
Where does the API key go?
In Muse Secrets, not chat. Name the key Muse so you can revoke it later without touching other keys.
Does this replace Muse’s Gmail or Outlook connector?
No. Keep them if Muse should search your mail. Mermail is the address Muse owns and receives at.
Why can’t Muse finish signups from my Gmail?
Muse strips verification codes from your Gmail on purpose. Codes for Muse’s own signups belong in a mailbox it owns.
Should I let Muse create a Gmail account for itself?
No. Give Muse a hosted Mermail address. Agent-created Gmail accounts are often disabled.
Does Muse see my Mermail API key?
The key stays in Secrets. Muse uses a stand-in token, so asking it to print secrets has nothing real to print.
Will Muse ask me before every send?
The first Mermail call needs approval. Grant a standing site permission, or keep a shorter grant.
Can Muse have more than one mailbox?
Yes on paid plans. Free includes 1 hosted mailbox. Reuse that address unless you need a separate side-chat mailbox.
Can I use my own domain?
Yes on a paid plan after you add and verify the domain. Hosted addresses use mermail.app.
How do I cut Muse off from its mailbox?
Delete the API key named Muse in Settings → API Keys. Other keys and mailboxes keep working.
Does the Secrets path unlock PayBox?
No. Project API keys cannot unlock PayBox or x402. Use Muse Code with muse mcp login mermail for OAuth.
How do I connect Muse Code instead?
Add the MCP URL in ~/.config/muse/settings.json with schema_version 1, then run muse mcp login mermail.
See all integrations
Integration indexClaude Code
Connect OAuth and install 15 skills for inbox, verification, and x402 workflows.
ChatGPTAdd Mermail as a custom OAuth app in an eligible ChatGPT workspace.
CodexConnect OAuth and install 15 skills for inbox and x402 workflows.
CursorAdd the hosted MCP server with OAuth—no API key required.
GrokConnect Mermail to Grok web chat and Grok Bot with OAuth, PayBox, and inline MCP Apps.
OpenClawConnect with OAuth, then verify Mermail with a live probe.
HermesAdd Mermail to Hermes with Streamable HTTP OAuth.