# Resend > Resend email API — send transactional emails, manage contacts, audiences, and domains. Supports HTML/text emails, batch sending, and domain verification via `robomotion resend`. Do NOT use for Gmail, Outlook, SendGrid, or other email services. - Skill: `robomotionio/resend` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add robomotionio/resend` - Raw SKILL.md: https://api.skillmd.com/api/skills/robomotionio/resend/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Web & Frontend - License: Apache-2.0 - Author: robomotionio (https://skillmd.com/u/robomotionio) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/robomotionio/resend --- # Resend The `robomotion resend` CLI connects to Resend for transactional email delivery. It sends emails (HTML and text), manages contacts and audiences, handles domain verification, and supports batch email operations. ## When to use - Send transactional emails with HTML or plain text content - Manage contacts and audience lists - Verify and manage sending domains - Send batch emails to multiple recipients ## Prerequisites - `robomotion` CLI installed - Package installed: `robomotion install resend` - Resend API key configured via Robomotion vault ## IMPORTANT: Session Mode Required for Multi-Step Operations Each CLI command runs as a **separate process** — connection IDs from `connect` do NOT persist across calls. You MUST use `--session` on `connect` and pass `--session-id` to all subsequent commands. ## Workflow 1. Install (once): `robomotion install resend` 2. Connect with session: ``` robomotion resend resend_connect --session --output json # → {"outClientId":"","session_id":""} ``` 3. Use the returned `client-id` and `session-id` in all subsequent commands: ``` robomotion resend resend_send_email --client-id "" --from --to --subject --html --session-id "" --output json ``` 4. Disconnect when done: ``` robomotion resend resend_disconnect --client-id "" --session-id "" --output json ``` **Always** append `--output json` to get structured JSON results. ## Commands Reference - `robomotion resend resend_connect --session --output json` Connects to Resend API and returns a client ID - `robomotion resend resend_disconnect --client-id --session-id "" --output json` Closes the Resend connection and releases resources - `robomotion resend resend_send_email --client-id --from --to --subject --body [--content-type] [--cc] [--bcc] [--reply-to] [--scheduled-at] [--tags] --session-id "" --output json` Sends an email through Resend - `robomotion resend resend_send_batch_email --client-id --emails --session-id "" --output json` Sends up to 100 emails in a single API call - `robomotion resend resend_get_email --client-id --email-id --session-id "" --output json` Retrieves details of a previously sent email by ID - `robomotion resend resend_create_contact --client-id --email [--first-name] [--last-name] [--unsubscribed] --session-id "" --output json` Creates a new contact in Resend - `robomotion resend resend_list_contacts --client-id [--20] [--after-cursor] --session-id "" --output json` Lists contacts from Resend with pagination support - `robomotion resend resend_get_contact --client-id --contact-id-or-email --session-id "" --output json` Retrieves a contact by ID or email address - `robomotion resend resend_update_contact --client-id --contact-id-or-email [--first-name] [--last-name] [--unsubscribed] --session-id "" --output json` Updates an existing contact's information - `robomotion resend resend_delete_contact --client-id --contact-id-or-email --session-id "" --output json` Deletes a contact by ID or email address - `robomotion resend resend_list_domains --client-id [--20] --session-id "" --output json` Lists all verified sending domains in Resend ## Environment - ROBOMOTION_API_TOKEN (if vault credentials are needed)