Resend

Create a new API key in Resend. The token is only shown once upon creation, so you MUST display it to the user.

create-api-key

**Purpose:** Create an automation workflow that triggers on events and executes a sequence of steps. **When to use:** - User wants to set up automated email sequences (welcome series, drip campaigns, re-engagement) - User wants to automate actions based on events (update contacts, add to segments) **Workflow:** manage-events (create event, if needed) → list-templates (to get template IDs) → get-template (to check if template has "from" and "subject" — if not, use list-domains to pick a verified domain for the step config) → create-automation → send-event (to test) **Returns:** Automation ID and dashboard link. The workflow is a JSON object with one key: "steps" — an array of step objects. Each step has: key (unique string), type, config, and either "next" (string|null) or "branches" (for branching steps). Use keys like: "trigger", "send_email_1", "delay_1", "condition_1", "wait_event_1". ## Step types ### trigger — starts the automation when an event fires (required, exactly one) config: { "eventName": "<event_name>" } Uses "next". ### send_email — send an email using a published template config: { "template": { "id": "<template_id>", "variables": { "<key>": "<value>" } }, "from": "Name <sender@example.com>", "subject": "Email subject", "replyTo": "<address>" } **"from" and "subject" are resolved from the step config first, then fall back to the template.** If neither provides a "from", the email will silently fail to send. If neither provides a "subject", the run will error. Best practice: always set "from" and "subject" on the step config so the automation is self-contained. Use list-domains to find verified domains for "from". "replyTo" and "variables" are optional. Variables can use { "var": "event.<field>" } or { "var": "contact.<field>" } for dynamic values. Uses "next". ### delay — pause the workflow config: { "duration": "<human-readable>" } Examples: "30 minutes", "1 hour", "2 days", "1 week". Max 30 days. Uses "next". ### condition — conditional split based on contact or event data config: A condition rule object: Single rule: { "type": "rule", "field": "event.<field>" or "contact.<field>", "operator": "<op>", "value": <value> } Compound: { "type": "and"|"or", "rules": [<rule>, ...] } Operators: eq, neq, gt, gte, lt, lte, contains, starts_with, ends_with, exists, is_empty. exists/is_empty do not require a value. Uses "branches": { "condition_met": "<step_key>", "condition_not_met": "<step_key_or_null>" } ### wait_for_event — pause until a specific event arrives or timeout config: { "eventName": "<event_name>", "timeout": "<human-readable>", "filterRule": <optional condition rule> } For email lifecycle events use "resend:email.<opened|clicked|bounced|delivered|complained|failed|suppressed>". Uses "branches": { "event_received": "<step_key>", "timeout": "<step_key_or_null>" } ### contact_update — update contact fields config: { "firstName": "<value>", "lastName": "<value>", "unsubscribed": true|false, "properties": { "<key>": "<value>" } } All fields optional. Values can use { "var": "event.<field>" } for dynamic data. Uses "next". ### contact_delete — remove the contact from the audience config: {} Uses "next". ### add_to_segment — add contact to a segment config: { "segmentId": "<segment_id>" } Uses "next". ## Rules 1. Every step must be reachable from the trigger via next/branches. 2. Terminal steps have "next": null (or null branch values). 3. The workflow must be tree-shaped — no merging branches back together. ## Example: Linear drip campaign { "steps": [ { "key": "trigger", "type": "trigger", "config": { "eventName": "user.created" }, "next": "send_email_1" }, { "key": "send_email_1", "type": "send_email", "config": { "template": { "id": "tmpl_123" }, "from": "Welcome <hello@example.com>", "subject": "Welcome!" }, "next": "delay_1" }, { "key": "delay_1", "type": "delay", "config": { "duration": "3 days" }, "next": "send_email_2" }, { "key": "send_email_2", "type": "send_email", "config": { "template": { "id": "tmpl_456" }, "from": "Welcome <hello@example.com>", "subject": "Getting started" }, "next": null } ] } ## Example: Re-engagement with wait_for_event { "steps": [ { "key": "trigger", "type": "trigger", "config": { "eventName": "user.created" }, "next": "send_email_1" }, { "key": "send_email_1", "type": "send_email", "config": { "template": { "id": "tmpl_789" }, "from": "Team <team@example.com>", "subject": "Welcome" }, "next": "wait_event_1" }, { "key": "wait_event_1", "type": "wait_for_event", "config": { "eventName": "resend:email.opened", "timeout": "3 days" }, "branches": { "event_received": null, "timeout": "send_email_2" } }, { "key": "send_email_2", "type": "send_email", "config": { "template": { "id": "tmpl_abc" }, "from": "Team <team@example.com>", "subject": "Did you miss this?" }, "next": null } ] } ## Example: Condition branch { "steps": [ { "key": "trigger", "type": "trigger", "config": { "eventName": "trial.ended" }, "next": "condition_1" }, { "key": "condition_1", "type": "condition", "config": { "type": "rule", "field": "event.converted", "operator": "eq", "value": true }, "branches": { "condition_met": "send_email_1", "condition_not_met": "send_email_2" } }, { "key": "send_email_1", "type": "send_email", "config": { "template": { "id": "tmpl_thanks" }, "from": "Team <team@example.com>", "subject": "Thanks for upgrading!" }, "next": null }, { "key": "send_email_2", "type": "send_email", "config": { "template": { "id": "tmpl_win_back" }, "from": "Team <team@example.com>", "subject": "We'd love to have you back" }, "next": null } ] }

create-automation

**Purpose:** Create a broadcast campaign (one email sent to an entire segment). Defines subject, body, and segment; does NOT send yet. Use send-broadcast to send it. **NOT for:** Sending a one-off email to specific people (use send-email). Not for adding contacts (use create-contact). **Returns:** Broadcast ID. Use this ID with send-broadcast to send, or get-broadcast/update-broadcast to manage. **When to use:** - User wants to "email my list", "send a newsletter", "broadcast to my segment", "email all contacts in X" - Newsletter, announcement, or bulk message to one segment - Supports personalization: {{{FIRST_NAME}}}, {{{LAST_NAME}}}, {{{EMAIL}}}, {{{RESEND_UNSUBSCRIBE_URL}}} **"All contacts" note:** Broadcasts require a segment. There is no "all contacts" option in the API. If the user wants to send to all contacts, check list-segments for an existing segment that covers everyone. If none exists, suggest creating one with create-segment. **Workflow:** list-segments (if needed) → create-broadcast → get-tiptap-json-content (with include_schema: true) → compose-broadcast → send-broadcast. **Content options after creating:** - **compose-broadcast** (recommended): Sets TipTap content that the user can visually edit in the Resend dashboard. Use this when the user wants to collaborate on or refine the email in the editor. - **update-broadcast with html/text**: Sets static HTML/text content. Use this only when the user explicitly wants to set raw HTML. Switching between compose and html/text modes is lossy — some content or formatting may be lost. Ask the user before switching.

create-broadcast

Create a new contact in Resend. Optionally assign to segments and configure topic subscriptions.

create-contact

Bulk-import contacts from a CSV file into Resend. The import is processed asynchronously: this returns an import ID immediately, then use get-contact-import to poll its status and counts. Provide the CSV as raw text via `content`. Max file size 100MB.

create-contact-import

Create a new contact property in Resend. A contact property is a custom attribute (e.g. "company_name", "plan_tier") that can be attached to contacts.

create-contact-property

Create a new domain in Resend. Returns DNS records that must be configured with your DNS provider for verification. You MUST display the DNS records to the user so they can set them up.

create-domain

Start a claim for a domain another Resend account has already verified. The domain is recreated under your account with brand-new DKIM keys, so the previous account's DNS records cannot be reused. Returns a TXT record that MUST be added to your DNS to prove ownership. You MUST display the TXT record to the user. After they add it, use verify-domain-claim, then poll get-domain-claim until status is "completed".

create-domain-claim

Create an inbox in Resend. An inbox receives email at an address on one of your domains and groups what arrives into threads. The domain must already be verified for receiving, or set forwarding to true, and Resend returns a receiving address you point your existing mail provider at instead. A team at the inbox limit of its plan gets a 403, and a blocked account gets a 451.

create-inbox

**Beta.** Only accounts in the Inboxes beta can use this tool. **Purpose:** Create a draft in a Resend inbox: a message saved for later, NOT sent. At least one of to, cc, bcc, subject, text, or html is required. Nothing leaves the account until send-inbox-draft is called on it. **NOT for:** Sending mail. To send straight away, use reply-to-inbox-thread-email to answer a thread, forward-inbox-thread-email to pass a message along, or send-email for an unrelated message. **Returns:** The draft's id. **When to use:** User asks to draft, compose, or prepare a message without sending it, or wants to read the wording back before it goes out. Pass threadId and replyToEmailId together to draft a reply to a message in a thread; omit both to draft a standalone message. The id this returns is the "draftId" that get-inbox-draft, update-inbox-draft, send-inbox-draft, and remove-inbox-draft all take.

create-inbox-draft

Create a label in a Resend inbox. A label is a tag the threads in that inbox can carry. Creating one does not put it on anything: pass the ID this returns to add-inbox-thread-labels to apply it to a thread. Resend picks a color when you omit one. Label names are unique per inbox, ignoring case, and an inbox can have at most 100 labels.

create-inbox-label

Create a new segment in Resend. A segment is a group of contacts that can be used to target specific broadcasts.

create-segment

Create a new email template in Resend. Templates are created in draft status. Use publish-template to make them available for sending. Variables use triple-brace syntax in HTML: {{{VAR_NAME}}}. **Workflow:** create-template → get-tiptap-json-content (with include_schema: true) → compose-template → publish-template. **Content options after creating:** - **compose-template** (recommended): Sets TipTap content that the user can visually edit in the Resend dashboard. Use this when the user wants to collaborate on or refine the template in the editor. - **update-template with html/text**: Sets static HTML/text content. Use this only when the user explicitly wants to set raw HTML. Switching between compose and html/text modes is lossy — some content or formatting may be lost. Ask the user before switching.

create-template

Create a new topic in Resend. Topics allow contacts to manage their subscription preferences for different types of emails.

create-topic

Create a new webhook in Resend. A webhook allows you to receive notifications at a specified URL when certain events occur (e.g. email.sent, email.delivered, email.bounced, inbox.email.received).

create-webhook

Remove agent presence from the Resend dashboard editor. Call this when done editing.

disconnect-from-editor

Duplicate an existing automation by ID or Resend dashboard URL. Creates a copy with its own ID, including the steps and connections of the original. Use this when the user wants a new automation based on one they already have, instead of rebuilding the workflow from scratch. Use update-automation on the new ID to rename it or change its workflow.

duplicate-automation

**Purpose:** Duplicate a broadcast by ID or Resend dashboard URL. Creates a new draft broadcast with the same segment, topic, sender, subject, reply-to, preview text, and content as the source, named after the source with " (copy)" appended (truncated to 70 characters). Any broadcast can be duplicated, including sent ones. **NOT for:** Editing the source broadcast (use update-broadcast) or sending the copy (use send-broadcast on the new draft's ID). **When to use:** User wants to "copy", "clone", "duplicate", or "reuse" an existing broadcast as the starting point for a new one.

duplicate-broadcast

Duplicate an existing email template in Resend. Creates a new draft copy of the template with a new ID. Accepts a template ID, alias, or Resend dashboard URL.

duplicate-template

Retrieve account-level email delivery and engagement metrics (sent, delivered, bounced, opened, clicked, etc.) for a date range, optionally broken down by period, domain, email, or broadcast.

get-email-metrics

**Purpose:** Forward one message from a Resend inbox thread to someone else. This sends a real email the moment you call it, from the inbox's address to the recipients named in "to", "cc" and "bcc". **NOT for:** Answering the sender (use reply-to-inbox-thread-email, which answers the message's author, or everyone on it with replyAll). Not for starting a new conversation from the inbox (use send-new-inbox-email). **Returns:** The sent email's id. **When to use:** User asks to forward a message in an inbox thread, pass it along, or loop someone in on it. Before using this tool, you MUST double-check with the user that they want to forward this message. Reference the RECIPIENTS, including any cc and bcc, and the SUBJECT when double-checking, and warn the user that forwarding cannot be undone: a sent email cannot be recalled, and every recipient keeps the original message. You may only use this tool if the user explicitly confirms they want to forward the message after you double-check. "to" is the only body field required: html and text are an optional note of your own, because the original message is carried either way. Across to, cc and bcc a forward can reach at most 50 recipients in total. The original message's attachments are sent with the forward; name any attachments you add in the double-check. A message whose original attachment was sent from a URL cannot be forwarded. Get the emailId from get-inbox-thread.

forward-inbox-thread-email

**Purpose:** Get details of a specific automation (with its workflow) or list all automations. **Modes:** - With `id`: Returns full automation details including the workflow definition. - Without `id`: Lists all automations with optional status filter and pagination. **When to use:** - User asks "show me my automations" or "what automations do I have?" - User wants to inspect a specific automation's workflow - Before update-automation, to see the current workflow

get-automation

**Purpose:** List runs for an automation, or get details of a specific run. **Modes:** - With `runId`: Returns detailed run info with step-by-step execution status, outputs, and errors. - Without `runId`: Lists runs for the automation with optional status filter. **When to use:** - User wants to see if an automation is working - User wants to debug a failed automation run - User asks "why did this automation fail?" or "show me recent runs" **Run statuses:** running, completed, failed, cancelled **Step statuses:** pending, running, completed, failed, skipped, waiting

get-automation-runs

Retrieve full details of a specific broadcast by ID or Resend dashboard URL (e.g. https://resend.com/broadcasts/<id>), including HTML and plain text content.

get-broadcast

Get a contact by ID or email from Resend.

get-contact

Get the status and counts of a contact import by ID. Use after create-contact-import to track progress (queued, in_progress, completed, failed).

get-contact-import

Get a contact property by ID from Resend.

get-contact-property

Get a domain by ID from Resend. Returns full domain details including DNS records needed for verification.

get-domain

Retrieve the latest claim for a domain by its placeholder Domain ID (the domain_id from create-domain-claim). Returns claim status and the TXT record needed to prove ownership. Poll until status is "completed".

get-domain-claim

Retrieve full details of a specific sent transactional email by ID, including message_id, HTML and plain text content.

get-email

Get an inbox by ID or email address from Resend, including its domain, receiving address, creation and update times, how many threads are unread, how many drafts it holds, and when it last received mail. When the user names the inbox by its address, pass the address directly. Otherwise use list-inboxes to find the ID. Use the returned ID with the other inbox tools.

get-inbox

Get the AI agent settings of a Resend inbox: the instructions the agent follows, the tone it writes in, and the actions it is allowed to take on the inbox's threads. An inbox whose agent was never configured returns empty settings: no instructions, no tone, no actions. The tone is one of the presets concise_professional, concise_casual, expanded_professional, expanded_casual.

get-inbox-agent

Get a draft by ID from a Resend inbox, body included: its recipients, subject, html and text, the files it carries, and the thread and message it replies to if it is a reply. A draft is one message being composed, so its body is returned here, unlike get-inbox-thread, which lists a whole conversation without the bodies. Use this to read a draft back before send-inbox-draft puts it in the mail. Get the draft ID from list-inbox-drafts.

get-inbox-draft

**Purpose:** Get one thread in a Resend inbox: the thread itself plus the metadata of its emails, oldest first. **NOT for:** Reading a message's body. This tool returns no html or text, because a whole conversation's bodies would flood the response. Use get-inbox-thread-email for one message's body. **Returns:** The thread's id, subject, folder, labels and read state, then for each email its email ID, direction (inbound or outbound), from, to, subject, received_at, read state, and how many attachments it carries. Emails are paginated: when more exist, pass the last email's ID back as "after". When paging backward with "before", pass the first email's ID back as "before". **When to use:** User wants to see a conversation, or you need a message's email ID. A message's ID IS the email ID that get-inbox-thread-email, reply-to-inbox-thread-email, and forward-inbox-thread-email take as their "emailId". Get the thread ID from list-inbox-threads or search-inbox-threads.

get-inbox-thread

**Purpose:** Read one message in a Resend inbox thread, body included: its html and text, its addresses and Message-ID, and the attachments it carries. **NOT for:** Reading a whole conversation at once (use get-inbox-thread, which lists a thread's messages without their bodies). Not for emails sent with send-email (use get-email), and not for mail at the account's Resend receiving address (use get-received-email). **Returns:** The message's email ID, direction (inbound or outbound), from, to, cc, bcc, reply_to, subject, message_id, read state, received_at, one line per attachment (filename, size and attachment ID), and the html and text bodies it has. **When to use:** get-inbox-thread points here for a body. Take the "Email ID" it printed for the message the user wants and pass it as emailId. Attachment contents cannot be downloaded through this server: attachments are listed, not fetched.

get-inbox-thread-email

**Purpose:** Get detailed information about a specific API request log, including the full request and response bodies. **Returns:** Log details: id, created_at, endpoint, method, response_status, user_agent, request_body, response_body. **When to use:** - User wants to inspect a specific API request - Debugging a particular API call - User says "show me that log", "what was in that request?"

get-log

Check for additional tools whenever your task might benefit from specialized capabilities - even if existing tools could work as a fallback.

get_more_tools

Retrieve full details of a specific received email by ID, including HTML and plain text content, headers, and raw email download URL.

get-received-email

Retrieve details of a specific attachment from a received email, including a time-limited download URL.

get-received-email-attachment

Get a segment by ID from Resend.

get-segment