Send a transactional email

Send a transactional email

Sends a published transactional email to one recipient, filled with the data variables you pass.

Pass transactionalId and email, plus dataVariables for the template (--var KEY=value on the CLI). Set addToAudience to also create the recipient as a contact, and send an Idempotency-Key header (--idempotency-key) so a retry never sends twice. Attachments work only after Loops support enables them. On the MCP server, find this operation with search, check its request shape with describe and run it with execute.

Set up

Use the first option your agent supports.

MCP (official, remote)

Add this server to your agent's MCP settings, then sign in when asked.

{ "mcpServers": { "loops": { "url": "https://mcp.loops.so" } } }

Call the MCP tool execute.

Server URL: https://mcp.loops.so

CLI (official)

Install the command, then confirm it runs.

brew install loops-so/tap/loops
loops --version

Run loops transactional send.

Set $LOOPS_API_KEY in your environment first (get a key: https://app.loops.so/settings?page=api).

API (official)

• Base URL: https://app.loops.so/api
• Endpoint: POST /v1/transactional
• Auth: send the header Authorization: Bearer $LOOPS_API_KEY
• Get a key: https://app.loops.so/settings?page=api
• Docs: https://loops.so/docs/api-reference/intro

Before doing anything else, make one read-only call to confirm access.

Rules

• Ask the user before anything that sends messages, costs money, or changes data.
• Never print API keys.