MailerSend

transactional email 23 tools available

MailerSend is a transactional email service designed for developers to integrate email sending capabilities into their applications.

Connect MailerSend Visit MailerSend

About this integration

Connect MailerSend to Definable to automate repetitive tasks, sync data with the rest of your stack, trigger on real-world events. Personas call MailerSend's 23 tools directly from chat or scheduled flows. You can wire it into any persona to read, write, and react when an event fires.

Connect MailerSend to Definable and it becomes a set of typed tools your agents plan with — triggered by events, run on schedules, or invoked mid-conversation. Every write is checked by the verifier before it lands.

Auth OAuth2 · 2 clicks

Tools 23 exposed

Plans All, incl. Free

Data Never trained on

MailerSend · in workflows

What teams actually run.

Three patterns teams run with MailerSend on day one. Each one is a plain-English prompt — no canvas, no glue code — and you can remix them into anything.

Trigger on event

│ Listen for a new event

│ Parse and validate the payload

└ Take an action with the linked tool

Daily summary

│ Pull yesterday's activity

│ Summarise with the model of your choice

└ Send the digest via email or Slack

Cross-tool sync

│ Read records from one app

│ Transform with a persona

└ Write the result back via this integration

23 tools available

The MailerSend toolbox.

Every MailerSend capability your agents can call, each with a typed schema the planner reads. The router picks the right tool per step; the verifier checks the result.

Create Sending Domain

Tool to add a new sending domain to MailerSend. Use when you need to register and configure a domain before sending emails.

Create SMTP User

Tool to create a new SMTP user. Use after domain setup to obtain SMTP credentials.

Create API Token

Creates a new API token with specified scopes (permissions) for a domain. The token allows programmatic access to MailerSend API endpoints based on granted scopes. WARNING: The token value is only displayed once upon creation and cannot be retrieved later.

Create Webhook

Tool to create a new webhook for a MailerSend domain. Use after you have a domain ID and need to receive event notifications like sent, delivered, opened, etc.

Delete Webhook

Tool to delete an existing webhook. Use when the webhook is no longer needed. Returns empty response on successful deletion (HTTP 204).

Get API Quota

Tool to retrieve current API usage quota. Use when monitoring API rate limits to avoid exceeding allowed calls.

Get Domain

Tool to retrieve detailed information about a specific sending domain in MailerSend. Returns domain verification status (DKIM, SPF, MX, tracking), settings (click/open tracking, paused status), and metadata (creation/update timestamps). Use this when you need to check if a domain is properly verified and configured for sending emails, or to review domain-specific tracking settings. Note: For detailed DNS record values, use the Get Domain DNS Records action.

List Domain Recipients

Tool to list recipients for a domain. Use after obtaining the domain ID to view recipients with optional pagination.

Get sending domains

Retrieve a paginated list of all sending domains configured in your MailerSend account. Use this to: - View all domains available for sending emails - Check domain verification and DNS status - Filter by verification status to find verified or unverified domains - Review domain settings like tracking and sending preferences Returns domain details including verification status, DNS configuration, and tracking settings.

Get general API resources

Tool to retrieve general API resources and information. Use when you need an overview of all MailerSend endpoints before constructing specific calls.

List Sender Identities

Retrieves a paginated list of sender identities configured in your MailerSend account. Sender identities are the email addresses or domains authorized to send emails through MailerSend. Each identity includes verification status, reply-to configuration, domain association, and optional personal notes. Use this tool to discover available sender identities before sending emails or to verify which identities are ready for use. Returns: Paginated list of identity objects with metadata including verification status, domain details, and navigation links for pagination.

Get sent messages

Tool to retrieve a paginated list of sent messages. Use after sending emails to view message logs.

Get email recipients

Tool to retrieve a list of email recipients. Use when you need to list and filter recipients by list ID or search term.

Get SMS Activity

Tool to retrieve SMS activity logs. Use when you need to fetch delivery status and logs of sent SMS messages.

Get SMS Inbounds

Retrieve inbound SMS route configurations. Inbound routes define rules for forwarding incoming SMS messages to webhook URLs based on message content filters. Use this action when you need to: - List all configured SMS inbound routes - Filter routes by SMS number or enabled status - Review webhook forwarding configurations and filter rules

List SMS Messages

Retrieves a paginated list of SMS messages sent through the MailerSend API. Returns message details including sender, recipients, content, status, and timestamps. Use this to review sent SMS messages and track their delivery status. Note: For detailed activity tracking with filters (date ranges, status, phone numbers), use the SMS Activity endpoint instead.

Get SMS Numbers

Tool to retrieve a paginated list of SMS phone numbers. Use after purchasing numbers to fetch available SMS numbers.

Get SMS recipients

Tool to retrieve a list of SMS recipients. Use when you need to list and paginate SMS recipients, optionally filtering by SMS number ID and/or recipient status.

Get SMTP users

Tool to retrieve a list of SMTP users. Use when you need to list and paginate SMTP users.

Get email templates

Retrieves a paginated list of email templates from your MailerSend account. Use this tool when you need to: - List all available email templates - Filter templates by domain ID - Browse templates with pagination - Check template details like name, type, and creation date Returns template metadata including IDs, names, types, and timestamps. For full template content, use a separate get single template endpoint.

Get API Tokens

Retrieves a paginated list of API tokens associated with your MailerSend account. Returns token details including ID, name, status, creation date, and assigned scopes/permissions. Requires 'tokens_full' scope.

Get users

Tool to retrieve a list of users associated with your account. Use after authenticating with a valid API token.

List webhooks

Tool to retrieve a list of webhooks. Use when you need to list and paginate all configured webhooks, optionally filtering by domain.

See it run

One prompt, start to finish.

A real prompt, the MailerSend tools it calls, and what comes back. This is the whole interface — describe the outcome, agents handle the rest.

❯

Run a real MailerSend task end-to-end — plan it, execute across the API, and hand back a verified result.

mailersend.create_sending_domain Tool to add a new sending domain to MailerSend. Use when you need to register and configur

mailersend.create_smtp_user Tool to create a new SMTP user. Use after domain setup to obtain SMTP credentials.

mailersend.create_api_token Creates a new API token with specified scopes (permissions) for a domain. The token allows · verified

done

Done. MailerSend responded across 3 calls, the verifier signed off, and the result is logged with every payload.

FAQ · MailerSend

Questions, answered.

What teams ask before connecting MailerSend.

01 What can I automate with MailerSend on Definable?

Anything MailerSend exposes through its API. Common transactional email workflows on Definable include automate repetitive tasks, sync data with the rest of your stack, trigger on real-world events. Personas can call any of the 23 MailerSend tools directly, then chain the result into another integration without you writing code.

02 How does MailerSend authentication work?

MailerSend uses API_KEY on Definable. You connect once from the integrations page, scoped to the permissions you choose, and from then on any persona that has the integration enabled can act on your behalf. Tokens are encrypted at rest and rotated automatically.

03 Is the MailerSend integration included in my Definable plan?

Yes — every Definable plan, including Starter, includes access to all 23 MailerSend tools. You only need a separate MailerSend subscription if MailerSend itself charges per seat or per API call.

04 Is using MailerSend through Definable secure?

Every call from a persona to MailerSend is logged with the user, persona, prompt, and response. Tokens never leave Definable's secrets vault, scopes are configurable per persona, and you can revoke access at any time from the integration page.

05 How do I get started with MailerSend on Definable?

Sign up for Definable, open the integrations page, find MailerSend, and connect via OAuth or API key. You can immediately attach MailerSend to any persona and start running workflows. The free Starter plan includes 5,000 credits/month.

06 What MailerSend actions does Definable expose?

Definable exposes all 23 MailerSend actions as callable tools — including `Create Sending Domain`, `Create SMTP User`, `Create API Token`, plus 20 more. Each tool gets a typed parameter schema so personas know exactly how to call it.