START HERE · Published 2026-10-06 · Updated 2026-10-06 · SecureSMTP
MCP server
Send email and manage sending domains from Claude, Cursor and any MCP client.
SecureSMTP runs an MCP (Model Context Protocol) server, so an AI assistant can send email, add and verify sending domains, and read your sending numbers.
https://securessmtp.com/api/mcpConnect
Claude Code
claude mcp add --transport http securessmtp https://securessmtp.com/api/mcpThe first time a tool is used, your browser opens a SecureSMTP sign-in page. Pick the site the assistant may act for and approve. This is OAuth 2.1 with dynamic client registration — no key is pasted anywhere.
Claude, Cursor and other clients
Add a remote MCP server with the URL above. Clients that support OAuth will open the sign-in page. Clients that only take a fixed token can send the site’s API key as a bearer token:
{
"mcpServers": {
"securessmtp": {
"url": "https://securessmtp.com/api/mcp",
"headers": {
"Authorization": "Bearer qcs_live_..."
}
}
}
}Every connection acts for one site — the one you approved, or the one the key belongs to.
Tools
| Tool | Inputs | What it does |
|---|---|---|
get_account | — | The site, the plan, the monthly email count and the number of sending domains. |
send_email | to (one address or a list of up to 50), subject, html and/or text, reply_to | Sends through POST /mail/send and returns its response. |
list_sending_domains | — | The site’s sending domains and their status. |
add_sending_domain | domain, from_address, align_mode (simple or advanced) | Adds a domain and returns the DNS records to publish. |
verify_domain | domain_id | Checks the DNS records and updates the status. |
get_deliverability | — | Counts of sent, delivered, bounced and other statuses over the last 30 days. |
Good to know
- Emails sent by an assistant count toward your monthly limit like any other relay-mode email.
- They show in the email log with source
mcp. - OAuth access tokens last one hour; the client renews them. To cut off an assistant that used the API key, rotate the key.