Rby Resend
Send an email
Sends one email from a verified domain to up to 50 recipients, now or at a scheduled time, and returns its ID.
Description
Pass `from`, `to`, `subject` and `html` or `text`, or a published `template` with its variables. Send an `Idempotency-Key` header (`--idempotency-key` on the CLI) so a retry never sends the email twice; keys expire after 24 hours. `scheduled_at` takes an ISO 8601 time or plain words such as `in 1 min`.
send-email.md
Send an email
Sends one email from a verified domain to up to 50 recipients, now or at a scheduled time, and returns its ID.
Pass from, to, subject and html or text, or a published template
with its variables. Send an Idempotency-Key header (--idempotency-key on
the CLI) so a retry never sends the email twice; keys expire after 24 hours.
scheduled_at takes an ISO 8601 time or plain words such as in 1 min.
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": { "resend": { "url": "https://mcp.resend.com/mcp" } } }
Call the MCP tool send-email.
Server URL: https://mcp.resend.com/mcp
CLI (official)
Install the command, then confirm it runs.
npm install -g resend-cli
resend --version
Run resend emails send.
Set $RESEND_API_KEY in your environment first (get a key: https://resend.com/api-keys).
API (official)
- Base URL: https://api.resend.com
- Endpoint:
POST /emails - Auth: send the header
Authorization: Bearer $RESEND_API_KEY - Get a key: https://resend.com/api-keys
- Docs: https://resend.com/docs/api-reference/introduction
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.
Built from these files in the repository
The layout and the rules come from lib/catalog/render-markdown.ts, the set-up wording from lib/catalog/render-access.ts.