Resend

Overview

Resend is the universal API for sending emails, designed for developers who need reliable deliverability and a simple integration experience. With the Resend integration in SquadOS, your agents can send transactional emails, manage audiences and contacts, configure verified domains, create reusable templates, and monitor events via webhooks in real time.

• Official website: https://resend.com/
• Composio documentation: docs.composio.dev/toolkits/resend

Authentication

This tool uses an API key (API_KEY) to connect.

You will need the following fields:

Field	Required	Description
api_key	Yes	API key generated in the Resend dashboard, used to authenticate all requests.

How to get credentials

1. Go to resend.com and create an account (or sign in).
2. In the dashboard, click API Keys in the side menu.
3. Click Create API Key, give it a descriptive name (e.g. “SquadOS”), and choose the desired permission level.
4. Copy the key shown — it is only displayed once.

Tip

Use a key with sending_access permission for SquadOS if you want to restrict the scope. If you need to manage domains, audiences, and settings, choose full_access.

How to connect in SquadOS

1. Go to Tools in the side menu (/admin/tools).
2. Open the Available tab and search for Resend.
3. Click the card to open the details modal and hit Connect.
4. You’re taken to the secure connection page hosted by Composio, where you enter the API key obtained above.
5. Once done, you’re sent back to SquadOS with the account connected and the tool available for your agents. (Connection-flow details in Organization Tools.)

Available actions

Add Contact To Segment

RESEND_ADD_CONTACT_TO_SEGMENT

Add an existing contact to a segment in Resend. Use when you need to organize contacts into specific segments for targeted communication.

Input parameters

Name	Type	Required	Description
contact_id	string	Yes	The ID of the contact to add to the segment.
segment_id	string	Yes	The ID of the segment to add the contact to.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Cancel Email

RESEND_CANCEL_EMAIL

Cancel a scheduled email.

Input parameters

Name	Type	Required	Description
id	string	Yes	The id of the email to cancel.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create API Key

RESEND_CREATE_API_KEY

Create a new API key to authenticate communications with Resend. Use when you need to generate a new authentication token for API access.

Input parameters

Name	Type	Required	Description
name	string	Yes	The API key name. Maximum 50 characters.
domain_id	string	No	Restrict an API key to send emails only from a specific domain. Only used when the permission is sending_access.
permission	string ("full_access" | "sending_access")	No	API key permission levels.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Audience

RESEND_CREATE_AUDIENCE

Create a list of contacts.

Input parameters

Name	Type	Required	Description
name	string	Yes	The name of the audience you want to create.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Contact

RESEND_CREATE_CONTACT

Create a contact in Resend.

Input parameters

Name	Type	Required	Description
email	string	Yes	The email address of the contact. Must be a valid RFC-compliant email address.
lastName	string	No	The last name of the contact.
firstName	string	No	The first name of the contact.
audienceId	string	Yes	The Audience ID.
unsubscribed	boolean	No	The subscription status.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Contact Property

RESEND_CREATE_CONTACT_PROPERTY

Tool to create a new contact property in Resend. Use when you need to define custom fields for contacts.

Input parameters

Name	Type	Required	Description
key	string	Yes	The key of the contact property. Must be alphanumeric and underscore only, max 50 characters. Case sensitive.
type	string ("string" | "number")	Yes	The type of the contact property.
fallbackValue	string	No	The fallback value for the property. Must match the type of the property.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Contact V2

RESEND_CREATE_CONTACT_V2

Tool to create a new contact in Resend. Use when you need to add a contact to Resend without specifying an audience.

Input parameters

Name	Type	Required	Description
email	string	Yes	The email address of the contact.
topics	array	No	List of topic subscriptions with ID and subscription status (opt_in or opt_out).
segments	array	No	List of segment IDs to enroll the contact in.
last_name	string	No	The last name of the contact.
first_name	string	No	The first name of the contact.
properties	array	No	Custom key-value pairs for the contact. Each property must have a key and value.
unsubscribed	boolean	No	Contact’s global subscription status; when true, the contact opts out of all broadcasts.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Domain

RESEND_CREATE_DOMAIN

Create a domain through the Resend Email API. The domain is created in a pending/unverified state and cannot be used for sending emails until DNS verification is completed.

Input parameters

Name	Type	Required	Description
name	string	Yes	The name of the domain to be created.
region	string ("us-east-1" | "eu-west-1" | "sa-east-1" | "ap-northeast-1")	No	The region where emails will be sent from. Supported values: us-east-1, eu-west-1, sa-east-1. Unsupported values cause validation errors.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Template

RESEND_CREATE_TEMPLATE

Tool to create a new email template in Resend. Use when you need to define reusable email templates with optional variables.

Input parameters

Name	Type	Required	Description
from	string	No	Sender email address. To include a friendly name, use the format 'Your Name <sender@domain.com>'.
html	string	Yes	The HTML version of the template. Use {{VARIABLE_NAME}} syntax to reference template variables.
name	string	Yes	The name of the template.
text	string	No	The plain text version of the template. If omitted, Resend will auto-generate from HTML.
alias	string	No	The alias of the template. This is an optional identifier that can be used instead of the template ID.
subject	string	No	Email subject for the template.
reply_to	string	No	Reply-to email address. For multiple addresses, send as an array of strings.
variables	array	No	Template variables. Up to 50 variables can be defined per template.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Topic

RESEND_CREATE_TOPIC

Tool to create a new topic to segment your audience. Use when you need to create a topic for organizing contacts by interests or preferences.

Input parameters

Name	Type	Required	Description
name	string	Yes	The topic name. Max length is 50 characters.
visibility	string ("public" | "private")	No	Topic visibility on the unsubscribe page.
description	string	No	The topic description. Max length is 200 characters.
defaultSubscription	string ("opt_in" | "opt_out")	Yes	The default subscription preference for new contacts. Accepts opt_in or opt_out. This value cannot be modified afterwards.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Create Webhook

RESEND_CREATE_WEBHOOK

Tool to create a webhook to receive real-time notifications about email events. Use when you need to set up automated notifications for email status changes.

Input parameters

Name	Type	Required	Description
events	array	Yes	Array of event types to subscribe to. Common events include: email.sent, email.delivered, email.delivery_delayed, email.complained, email.bounced, email.opened, email.clicked. Must include at least one event.
endpoint	string	Yes	The URL where webhook events will be sent. Must be a valid HTTPS endpoint.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete API Key

RESEND_DELETE_API_KEY

Remove an existing API key from Resend. Use when you need to revoke or delete an API key.

Input parameters

Name	Type	Required	Description
api_key_id	string	Yes	The API key ID to delete.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Audience

RESEND_DELETE_AUDIENCE

Remove an existing audience.

Input parameters

Name	Type	Required	Description
audience_id	string	Yes	The ID of the audience to delete.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Contact

RESEND_DELETE_CONTACT

Delete a contact in Resend.

Input parameters

Name	Type	Required	Description
id	string	No	The Contact ID. Either id or email must be provided.
email	string	No	The Contact email. Either id or email must be provided.
audienceId	string	Yes	The Audience ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Contact By ID

RESEND_DELETE_CONTACT_BY_ID

Tool to remove an existing contact by its ID. Use when you need to delete a contact directly without specifying an audience.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Contact ID to delete.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Contact Property

RESEND_DELETE_CONTACT_PROPERTY

Remove an existing contact property from Resend.

Input parameters

Name	Type	Required	Description
contact_property_id	string	Yes	The Contact Property ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Domain

RESEND_DELETE_DOMAIN

Delete a domain through the Resend Email API. Deletion is irreversible; ensure no active email traffic or DNS configurations depend on the domain before calling.

Input parameters

Name	Type	Required	Description
domain_id	string	Yes	The id of the domain to delete.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Segment

RESEND_DELETE_SEGMENT

Remove an existing segment. Use when you need to permanently delete a segment by its ID.

Input parameters

Name	Type	Required	Description
segment_id	string	Yes	The ID of the segment to delete.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Template

RESEND_DELETE_TEMPLATE

Remove an existing template. Use this action when you need to delete a template from Resend.

Input parameters

Name	Type	Required	Description
template_id	string	Yes	The Template ID or alias.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Topic

RESEND_DELETE_TOPIC

Tool to remove an existing topic in Resend. Use when you need to delete a topic.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Topic ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Delete Webhook

RESEND_DELETE_WEBHOOK

Remove an existing webhook. Use this to delete a webhook configuration when you no longer need to receive event notifications at that endpoint.

Input parameters

Name	Type	Required	Description
webhook_id	string	Yes	The Webhook ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Duplicate Template

RESEND_DUPLICATE_TEMPLATE

Duplicate an existing template through the Resend Email API. Use when you need to create a copy of an existing template.

Input parameters

Name	Type	Required	Description
template_id	string	Yes	The Template ID or alias to duplicate.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Contact

RESEND_GET_CONTACT

Tool to retrieve a single contact from Resend by ID or email. Use when you need to get details of a specific contact using the global contacts endpoint.

Input parameters

Name	Type	Required	Description
contact_id	string	Yes	The Contact ID or email address to retrieve. Can be either a UUID (e.g., 'e169aa45-1ecf-4183-9955-b1499d5701d3') or an email address (e.g., 'user@example.com').

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Contact Property

RESEND_GET_CONTACT_PROPERTY

Tool to retrieve a single contact property from Resend. Use when you need to get details about a specific contact property by its ID.

Input parameters

Name	Type	Required	Description
contact_property_id	string	Yes	The Contact Property ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Email Attachment

RESEND_GET_EMAIL_ATTACHMENT

Retrieve a single attachment from a sent email. Use when you need to access attachment metadata and download URL.

Input parameters

Name	Type	Required	Description
email_id	string	Yes	The ID of the email.
attachment_id	string	Yes	The ID of the attachment.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Segment

RESEND_GET_SEGMENT

Retrieve a single segment by its ID. Use when you need to get detailed information about a specific segment.

Input parameters

Name	Type	Required	Description
segment_id	string	Yes	The ID of the segment to retrieve.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Template

RESEND_GET_TEMPLATE

Retrieve a single template by ID or alias from Resend. Use when you need to view template details.

Input parameters

Name	Type	Required	Description
template_id	string	Yes	The Template ID or alias to retrieve.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Topic

RESEND_GET_TOPIC

Tool to retrieve a single topic by its ID in Resend. Use when you need to fetch details of a specific topic.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Topic ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Get Webhook

RESEND_GET_WEBHOOK

Retrieve a single webhook for the authenticated user. Use this to get details about a specific webhook configuration including its endpoint, subscribed events, and signing secret.

Input parameters

Name	Type	Required	Description
webhook_id	string	Yes	The Webhook ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List All Contacts

RESEND_LIST_ALL_CONTACTS

Tool to retrieve a list of all contacts from Resend. Use when you need to fetch contacts across all audiences with optional pagination.

Input parameters

Name	Type	Required	Description
after	string	No	Pagination cursor - retrieves contacts after this ID (the ID itself is excluded). Cannot be used with the before parameter.
limit	integer	No	Number of contacts to retrieve per request. Minimum 1, maximum 100. If not provided, defaults to 20.
before	string	No	Pagination cursor - retrieves contacts before this ID (the ID itself is excluded). Cannot be used with the after parameter.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List API Keys

RESEND_LIST_API_KEYS

Tool to retrieve a list of API keys for the authenticated user. Use when you need to view all API keys associated with the account, including pagination support for large result sets.

Input parameters

Name	Type	Required	Description
after	string	No	The ID after which we’ll retrieve more API keys (for pagination). This ID will not be included in the returned list. Cannot be used with the before parameter.
limit	integer	No	Number of API keys to retrieve. If omitted, all keys are returned in a single response.
before	string	No	The ID before which we’ll retrieve more API keys (for pagination). This ID will not be included in the returned list. Cannot be used with the after parameter.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Audiences

RESEND_LIST_AUDIENCES

List all audiences.

Input parameters

Name	Type	Required	Description
after	string	No	Cursor ID for forward pagination.
limit	integer	No	Maximum number of results to return. Max: 100.
before	string	No	Cursor ID for backward pagination.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Broadcasts

RESEND_LIST_BROADCASTS

Tool to retrieve a list of broadcasts. Use when you need to fetch all broadcasts or paginate through them.

Input parameters

Name	Type	Required	Description
after	string	No	The ID after which we’ll retrieve more broadcasts (for pagination). This ID will not be included in the returned list. Cannot be used with the before parameter.
limit	integer	No	Number of broadcasts to retrieve. If not provided, all broadcasts will be returned.
before	string	No	The ID before which we’ll retrieve more broadcasts (for pagination). This ID will not be included in the returned list. Cannot be used with the after parameter.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Contact Properties

RESEND_LIST_CONTACT_PROPERTIES

Tool to retrieve a list of contact properties from Resend. Use when you need to view available contact property definitions.

Input parameters

Name	Type	Required	Description
after	string	No	Return items after this cursor.
limit	integer	No	Number of items to return.
before	string	No	Return items before this cursor.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Contacts

RESEND_LIST_CONTACTS

List contacts in Resend.

Input parameters

Name	Type	Required	Description
after	string	No	Cursor ID for forward pagination.
limit	integer	No	Maximum number of results to return. Max: 100.
before	string	No	Cursor ID for backward pagination.
audienceId	string	Yes	The Audience ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Contact Segments

RESEND_LIST_CONTACT_SEGMENTS

Retrieve a list of segments that a contact is part of. Use when you need to determine which segments a specific contact belongs to.

Input parameters

Name	Type	Required	Description
id	string	Yes	The ID of the contact.
after	string	No	Cursor ID for forward pagination.
limit	integer	No	Maximum number of results to return. Max: 100.
before	string	No	Cursor ID for backward pagination.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Contact Topics

RESEND_LIST_CONTACT_TOPICS

Retrieve a list of topic subscriptions for a contact in Resend. Use when you need to check which topics a specific contact is subscribed to.

Input parameters

Name	Type	Required	Description
after	string	No	Cursor ID for forward pagination.
limit	integer	No	Maximum number of results to return. Max: 100.
before	string	No	Cursor ID for backward pagination.
contact_id	string	Yes	The ID of the contact.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Domains

RESEND_LIST_DOMAINS

List all domains. Use the returned domain IDs as inputs for tools like RESEND_VERIFY_DOMAIN that require a domain_id.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Email Attachments

RESEND_LIST_EMAIL_ATTACHMENTS

Tool to retrieve a list of attachments from a sent email. Use when you need to get information about files attached to an email sent via Resend.

Input parameters

Name	Type	Required	Description
after	string	No	Pagination cursor to fetch results after this attachment ID. Cannot be used with before.
limit	integer	No	Maximum number of attachments to return. Use for pagination.
before	string	No	Pagination cursor to fetch results before this attachment ID. Cannot be used with after.
email_id	string	Yes	The ID of the email to retrieve attachments from.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Emails

RESEND_LIST_EMAILS

Tool to retrieve a list of emails sent by your team. Use when you need to fetch outbound emails from your account. Supports pagination with limit, after, and before parameters.

Input parameters

Name	Type	Required	Description
after	string	No	Pagination cursor to fetch results after this email ID. Cannot be used with before.
limit	integer	No	Maximum number of emails to return. Default 20, max 100, min 1.
before	string	No	Pagination cursor to fetch results before this email ID. Cannot be used with after.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Received Emails

RESEND_LIST_RECEIVED_EMAILS

Tool to retrieve a list of received emails for the authenticated user. Use when you need to fetch incoming emails from the receiving endpoint.

Input parameters

Name	Type	Required	Description
after	string	No	Pagination cursor to fetch results after this email ID. Cannot be used with before.
limit	integer	No	Maximum number of received emails to return.
before	string	No	Pagination cursor to fetch results before this email ID. Cannot be used with after.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Segments

RESEND_LIST_SEGMENTS

Tool to retrieve a list of segments from Resend. Use when you need to view all available segments for audience management.

Input parameters

Name	Type	Required	Description
after	string	No	Return items after this cursor for pagination.
limit	integer	No	Number of items to return.
before	string	No	Return items before this cursor for pagination.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Templates

RESEND_LIST_TEMPLATES

Tool to retrieve a list of templates from Resend. Use when you need to get all available templates with optional pagination support.

Input parameters

Name	Type	Required	Description
after	string	No	Return items after this cursor.
limit	integer	No	Number of items to return.
before	string	No	Return items before this cursor.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Topics

RESEND_LIST_TOPICS

Tool to retrieve a list of topics for the authenticated user. Use when you need to fetch available topics with optional pagination support.

Input parameters

Name	Type	Required	Description
after	string	No	Return items after this cursor.
limit	integer	No	Number of items to return.
before	string	No	Return items before this cursor.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

List Webhooks

RESEND_LIST_WEBHOOKS

Retrieve a list of webhooks for the authenticated user. Use this to view all configured webhooks with their endpoints, event types, and status.

Input parameters

Name	Type	Required	Description
after	string	No	Pagination cursor to fetch results after this webhook ID. Cannot be used with before.
limit	integer	No	Maximum number of webhooks to return.
before	string	No	Pagination cursor to fetch results before this webhook ID. Cannot be used with after.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Publish Template

RESEND_PUBLISH_TEMPLATE

Publish a template through the Resend Email API. Use when you need to make a template publicly available.

Input parameters

Name	Type	Required	Description
template_id	string	Yes	The Template ID or alias to publish.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Remove Contact From Segment

RESEND_REMOVE_CONTACT_FROM_SEGMENT

Remove an existing contact from a segment. Use when you need to disassociate a contact from a specific segment.

Input parameters

Name	Type	Required	Description
contact_id	string	Yes	The ID of the contact to remove from the segment.
segment_id	string	Yes	The ID of the segment to remove the contact from.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Retrieve Audience

RESEND_RETRIEVE_AUDIENCE

Retrieve a single audience.

Input parameters

Name	Type	Required	Description
audience_id	string	Yes	The ID of the audience to retrieve.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Retrieve Contact

RESEND_RETRIEVE_CONTACT

Retrieve a contact in Resend.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Contact ID.
audienceId	string	Yes	The Audience ID.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Retrieve Domain

RESEND_RETRIEVE_DOMAIN

Retrieve a single domain.

Input parameters

Name	Type	Required	Description
domain_id	string	Yes	The id of the domain to retrieve.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Retrieve Email

RESEND_RETRIEVE_EMAIL

Retrieve a single email.

Input parameters

Name	Type	Required	Description
email_id	string	Yes	The id of the email to retrieve.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Send Batch Emails

RESEND_SEND_BATCH_EMAILS

Trigger up to 100 batch emails at once. Use when you need to send multiple emails in a single API request.

Input parameters

Name	Type	Required	Description
emails	array	Yes	List of email items to send in batch. Maximum 100 emails per batch.
Idempotency-Key	string	No	A unique identifier for the request to ensure emails are only sent once.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Send Email

RESEND_SEND_EMAIL

Send an email using Resend. Confirm recipients and content with the user before invoking — sends are irreversible. All recipients must be listed explicitly via to, cc, or bcc; audience-based sending is unsupported. Render HTML or plain text externally before passing via html or text.

Input parameters

Name	Type	Required	Description
cc	string	No	Cc recipient email address. For multiple addresses, send as an array of strings.
to	string	Yes	Recipient email address. For multiple addresses, send as an array of strings. Max 50.
bcc	string	No	Bcc recipient email address. For multiple addresses, send as an array of strings. Use bcc instead of to when sending to multiple recipients to prevent them from seeing each other’s addresses.
from	string	Yes	Sender email address. To include a name, use the format 'Your Name <sender@domain.com>'.
html	string	No	The HTML version of the message. At least one of html or text must be provided.
text	string	No	The plain text version of the message. At least one of html or text must be provided.
react	string	No	The React version of the message. Only available in the Node.js SDK.
headers	object	No	Custom headers to add to the email. Must be a dictionary/object with key-value pairs (e.g., {'X-Custom-Header': 'value'}). Pass None or omit to exclude.
subject	string	Yes	Email subject.
reply_to	string	No	Reply-to email address. For multiple addresses, send as an array of strings.
scheduled_at	string	No	Schedule email to be sent later. The date should be in ISO 8601 format (e.g., '2024-08-05T11:52:01.858Z').

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Broadcast

RESEND_UPDATE_BROADCAST

Update an existing broadcast in Resend. Use when you need to modify broadcast details like name, subject, content, or recipients.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Broadcast ID to update.
from	string	No	The email address of the sender.
html	string	No	The HTML version of the message.
name	string	No	Name of the broadcast.
text	string	No	The plain text version of the message.
subject	string	No	The subject line of the email.
reply_to	array	No	The email addresses to which replies should be sent.
segment_id	string	No	Unique identifier of the segment this broadcast will be sent to.
audience_id	string	No	Unique identifier of the audience this broadcast will be sent to.
preview_text	string	No	The preview text of the email.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Contact

RESEND_UPDATE_CONTACT

Tool to update an existing contact in Resend by ID or email. Use when you need to modify contact details such as name or subscription status.

Input parameters

Name	Type	Required	Description
last_name	string	No	The last name of the contact.
first_name	string	No	The first name of the contact.
id_or_email	string	Yes	The Contact ID or email address to update. Can be either the unique contact ID (UUID format) or the contact’s email address.
unsubscribed	boolean	No	The subscription status of the contact. When true, unsubscribes the contact from all broadcasts.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Contact Property

RESEND_UPDATE_CONTACT_PROPERTY

Update an existing contact property in Resend. Only the fallback_value can be updated; the key and type fields cannot be changed after creation.

Input parameters

Name	Type	Required	Description
fallback_value	string	No	The default value to use when the property is not set for a contact. Must match the type specified in the contact property’s type field. Can be a string or number.
contact_property_id	string	Yes	The Contact Property ID to update.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Domain

RESEND_UPDATE_DOMAIN

Update an existing domain.

Input parameters

Name	Type	Required	Description
tls	string ("opportunistic" | "enforced")	No	TLS setting for email communication. opportunistic: Always attempts to make a secure connection. enforced: Requires TLS for email communication.
domain_id	string	Yes	The id of the domain to update.
open_tracking	boolean	No	Track the open rate of each email.
click_tracking	boolean	No	Track clicks within the body of each HTML email.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Email

RESEND_UPDATE_EMAIL

Update a scheduled email.

Input parameters

Name	Type	Required	Description
id	string	Yes	The ID of the email to update.
scheduled_at	string	Yes	Schedule email to be sent later. The date should be in ISO 8601 format (e.g: 2024-08-05T11:52:01.858Z).

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Template

RESEND_UPDATE_TEMPLATE

Tool to update an existing email template in Resend. Use when you need to modify template properties such as name, subject, HTML content, or variables.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Template ID or alias to update.
from	string	No	Sender email address. To include a friendly name, use the format "Your Name <sender@domain.com>".
html	string	No	The HTML version of the template.
name	string	No	The name of the template.
text	string	No	The plain text version of the template.
alias	string	No	The alias of the template.
subject	string	No	Email subject.
reply_to	array	No	Reply-to email addresses.
variables	array	No	Template variables with their types and optional fallback values.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Topic

RESEND_UPDATE_TOPIC

Tool to update an existing topic in Resend. Use when you need to modify the name of a topic.

Input parameters

Name	Type	Required	Description
id	string	Yes	The Topic ID to update.
name	string	Yes	The name of the topic to update.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Update Webhook

RESEND_UPDATE_WEBHOOK

Tool to update an existing webhook configuration. Use when you need to modify the endpoint URL, change event subscriptions, or enable/disable a webhook.

Input parameters

Name	Type	Required	Description
events	array	No	Array of event types to subscribe to. Must contain at least one event if provided.
status	string ("enabled" | "disabled")	No	The status of the webhook. Set to enabled to activate or disabled to deactivate.
endpoint	string	No	The URL where webhook events will be sent.
webhook_id	string	Yes	The ID of the webhook to update.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.

Verify Domain

RESEND_VERIFY_DOMAIN

Verify a domain through the Resend Email API. DNS records must fully propagate before verification succeeds; avoid immediate retries after DNS setup.

Input parameters

Name	Type	Required	Description
domain_id	string	Yes	The id of the domain to verify. Must match an existing registered domain; use RESEND_LIST_DOMAINS to retrieve valid IDs.

Output

Name	Type	Required	Description
data	string	Yes	Data from the action execution.
error	string	No	Error if any occurred during the execution of the action.
successful	boolean	Yes	Whether or not the action execution was successful.