Meta Muse
Meta Muse can use a ReplyLayer mailbox as your agent's own email address. Muse builds a custom connector from ReplyLayer's public API description and calls the REST API. It does not use the MCP server. ReplyLayer is separate from Gmail: this setup does not connect a Gmail account.
Before you start
- A mailbox that lets agents send. In the dashboard, open Mailboxes,
choose the mailbox, and check that What agents can do is Send and
draft. With Draft only or Read only, the test send fails with
AGENT_SENDING_DISABLED. Saving the change asks you to confirm your sign-in. - A mailbox that can start a new email. After you upgrade from the trial,
the trial mailbox keeps receiving and can reply in existing threads, but a new
email from it fails with
ESTATE_CONTINUITY_REPLY_ONLY. Use a mailbox on your own ReplyLayer domain. See Tiers, quotas, and sandbox limits. - An agent key for that mailbox, created on app.replylayer.ai. The full key is shown once. A key from a different ReplyLayer environment, such as a test or staging dashboard, is refused. See Creating a key.
- The test address allowed, if the mailbox uses a recipient allowlist. The
test sends to
[email protected], the email simulator's success address. On an allowlist mailbox, allow that address first. Connect Agent has a button for it. See Recipient allowlist.
Connect Muse
- In the dashboard, open Connect Agent, choose the mailbox, open the REST API tab, and choose Meta Muse.
- Create the agent key in Step 2 if you do not have one.
- Copy the test prompt. It names your mailbox and a test token. It never contains your key.
- Start a new chat in Muse and paste the prompt.
- When Muse shows its ReplyLayer connector card, choose Connect and paste the key into the credential prompt that opens. This is the only place the key goes. Never paste it into the chat.
- When Muse asks to share info with
api.replylayer.ai, allow it.
Muse lists your mailboxes, sends one email to the simulator, and reports the result.
Reading the result
Muse reports email_effect.effect_status and the message id.
Send outcomes defines every value.
sent: ReplyLayer accepted the test email. It does not confirm delivery.held_for_review: the email is waiting for a person on your account to approve or deny it in the dashboard. Muse cannot approve it.held_infrastructure: a temporary problem held the email before it was checked. Wait, then choose Start a new test on Connect Agent and paste the new prompt. The same prompt returns the same hold.blocked: ReplyLayer refused the email. Do not ask Muse to rewrite it. See Content scanning.
Pasting the same prompt again never sends a second email. ReplyLayer returns the
first result for the same Idempotency-Key.
If Muse reports an error
| Muse reports | What to do |
|---|---|
401 | ReplyLayer refused the key. Check that it is an active agent key created on app.replylayer.ai for this mailbox. If you no longer have it, create a new one and give it to Muse through its credential prompt. |
429 | Too many requests. Wait before trying again, and do not ask Muse to retry in a loop. If it follows a 401, fix the key first. |
AGENT_SENDING_DISABLED | Set What agents can do to Send and draft on the mailbox page, then paste the same prompt again. |
ESTATE_CONTINUITY_REPLY_ONLY | Choose a mailbox on your own ReplyLayer domain on Connect Agent, create a key for it, and paste the new prompt. |
RECIPIENT_NOT_ON_ALLOWLIST | Allow [email protected] on that mailbox, then paste the same prompt again. |
RECIPIENT_AGENT_CONTAINED | Stop. Why a send was refused explains who can lift it. |
| An answer with no new request | Muse may answer from an earlier result. Ask it to make the HTTP request again with the same Idempotency-Key. |
After the test
Muse keeps the connector. It can call other operations in the API description, limited to what an agent key for this mailbox may do. See Roles: admin vs agent.
Muse has no settings page for a connector's key. To replace the key, create a new agent key, then ask Muse in a chat to replace the API key for its ReplyLayer connector. Muse shows the connector card again: choose Connect and enter the new key in the window that opens, never in the chat. Check that Muse can list your mailboxes, then revoke the old key. See Rotating keys. A revoked key stops working in Muse at once.