curl -X POST 'https://api.resend.com/events/send' \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{
  "event": "string",
  "contact_id": "00000000-0000-4000-8000-000000000000",
  "email": "string",
  "payload": {}
}'

# POST /events/send (Resend API)
Base URL: https://api.resend.com
Auth: Authorization: Bearer <RESEND_API_KEY>
Last verified: 2026-09-03

> Send an event

## Critical Gotchas
* All requests must include a `User-Agent` header (e.g. `User-Agent: my-app/1.0`) or the API returns HTTP 403.
* The `to` field is an array of strings, even when sending to a single recipient.

## cURL
curl -X POST 'https://api.resend.com/events/send' \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H 'User-Agent: my-app/1.0' \
  -H 'Content-Type: application/json' \
  -d '{"event":"string","contact_id":"00000000-0000-4000-8000-000000000000","email":"string","payload":{}}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| event | body | string | Yes | The name of the event to send. |
| contact_id | body | string | No | The ID of the contact to associate wi... |
| email | body | string | No | The email address to associate with t... |

## Response (200 OK)
{"object":"event","event":"string"}

---
Need an API key? Get one at https://resend.com/signup

POST

/events/send

Resend API

Send an event

Base URL: https://api.resend.com
Auth: Authorization: Bearer <RESEND_API_KEY>
Last verified: 2026-09-03 · upstream hash matched

Actions

Agents: curl -H "Accept: text/markdown" this URL
→ 218 tokens · Vary: Accept

Critical gotchas

All requests must include a User-Agent header (e.g. User-Agent: my-app/1.0) or the API returns HTTP 403.

The to field is an array of strings, even when sending to a single recipient.

cURL

curl -X POST 'https://api.resend.com/events/send' \  -H "Authorization: Bearer $RESEND_API_KEY" \  -H 'User-Agent: my-app/1.0' \  -H 'Content-Type: application/json' \  -d '{  "event": "string",  "contact_id": "00000000-0000-4000-8000-000000000000",  "email": "string",  "payload": {}}'

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Parameters

Name	In	Type	Required	Description
event	body	string	Yes	The name of the event to send.
contact_id	body	string	No	The ID of the contact to associate with this event. Exactly one of `contact_id` or `email` must be provided.
email	body	string	No	The email address to associate with this event. Exactly one of `contact_id` or `email` must be provided.
payload	body	object	No	An optional payload of key/value pairs to include with the event.

Response 200 OK

{
  "object": "event",
  "event": "string"
}