--- title: "Connect Harpoon and MailerLite Classic - APIANT.ai" description: "When \"New Client\" fires in Harpoon, your agent runs \"Add Subscriber to Group\" in MailerLite Classic." canonical: "https://apiant.ai/connect/harpoon-to-mailerlite-classic" --- # Connect Harpoon and MailerLite Classic When **New Client** fires in [Harpoon](https://apiant.ai/connections/harpoon), your agent runs **Add Subscriber to Group** in [MailerLite Classic](https://apiant.ai/connections/mailerlite-classic), or **New Group** in MailerLite Classic to **Add Invoice** in Harpoon. Describe the whole flow and it is built, tested on every scenario and kept running. Harpoon **9** triggers Harpoon **46** actions MailerLite Classic **1** trigger MailerLite Classic **18** actions What the catalog holds today. Ask for anything missing and your agent reads the API documentation and adds it. ## What do you want Harpoon and MailerLite Classic to do together? Give your AI client this address. `https://mcp.apiant.ai` One connection does both: ask your client to act in an app once, or have it build an automation that keeps running. Any client that takes a remote MCP server. Nothing to install. Create your free account, then sign in once in your browser. ### Set it up in your client ### Claude Code Run this in the directory you want to work in. `claude mcp add --transport http -s project apiant-ai https://mcp.apiant.ai` Start Claude Code there, approve the server, and sign in in the browser page it opens. [Claude Code guide (opens in a new tab)](https://apiant.ai/docs/mcp/claude-code) ### Claude, web and desktop Open Customize, then Connectors, then Add custom connector, and paste the address. On Team and Enterprise an owner adds it first. [Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp) ### Cursor Add the address to your MCP configuration as a server URL. Cursor signs you in in your browser. [Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp) ### Zed Open Settings, then AI, then MCP Servers, then Add Server, then Add Remote Server. [Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp) ### Codex and the ChatGPT desktop app Open Settings, then MCP servers, then Add server, and choose Streamable HTTP. From the terminal, Codex takes the address with its own add command and then signs you in. [Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp) ### Any other MCP client Paste the address where the client asks for a remote MCP server URL, and name the server apiant-ai where it lets you. APIANT's skills reach the client over the same connection. [Setup guide (opens in a new tab)](https://apiant.ai/docs/mcp) Example flows ## What Harpoon and MailerLite Classic can do together ### From Harpoon to MailerLite Classic - When **New Client** in Harpoon then **Add Subscriber to Group** in MailerLite Classic - When **New Contact** in Harpoon then **Create Campaign** in MailerLite Classic ### From MailerLite Classic to Harpoon - When **New Group** in MailerLite Classic then **Add Invoice** in Harpoon - When **New Group** in MailerLite Classic then **Add Lead Source** in Harpoon Starting points drawn from the triggers and actions in the catalog today. Describe the flow you need, at any depth, and your agent builds it and tests every scenario before it ships. Everything your agent can do with Harpoon and MailerLite Classic ## Triggers and actions 10 triggers · 64 actions - Trigger **New Client** Triggered when a new client is created in Harpoon. - Trigger **New Contact** Triggered when a new contact is created in Harpoon. - Trigger **New Expense** Triggered when a new expense is created in your Harpoon account. - Trigger **New Expense Category** Triggered when a new expense category is created in Harpoon. - Trigger **New Invoice** Triggered when a new invoice is created in Harpoon. - Trigger **New Payment** Triggered when a new payment is recorded in your Harpoon account. - Trigger **New Project** Triggered when a new project is created in Harpoon. - Trigger **New Task Category** Triggered when a new task category is added in your Harpoon account. - Trigger **New Time Entry** Triggered when a new time entry is logged in Harpoon. - Action **Add Credit Entry** Creates a new credit entry on a client's account in Harpoon, recording an amount, a date and an optional note or originating invoice. Returns the credit entry that was created. - Action **Add Invoice** Creates a new invoice in Harpoon for a client or project, with an invoice number, issue date, and optional line items. Returns the invoice that was created. - Action **Add Lead Source** Creates a new lead source in Harpoon, so new clients can be tagged with where they came from. Returns the lead source that was created. - Action **Add Note** Adds a note to a client, project or invoice in Harpoon. Returns the note that was created. - Action **Add Team** Creates a new team in your Harpoon account. Harpoon populates the new team from your account details; the API accepts no team attributes on creation. - Action **Clone Time Entry** Creates a copy of an existing time entry in Harpoon. The copy keeps the original's project, task and description, and starts with today's date and zero hours logged. - Action **Create Contact** Creates a contact person under a Harpoon client, with their name, email address, and phone number. Returns the contact that was created. - Action **Create Expense** Records a one-off expense in Harpoon with its date, amount, and vendor, optionally attributed to a client, project, or expense category. Returns the expense that was created. - Action **Create Expense Category** Creates a new expense category in your Harpoon account so expenses can be grouped under it. - Action **Create Project** Creates a project in Harpoon for a client, with its budget, rate, and start and end dates. Returns the project that was created. - Action **Create Time Entry** Logs hours worked in Harpoon for a team member on a given date, optionally against a client or project. Returns the time entry that was created. - Action **Delete Client** Deletes a client from your Harpoon account. - Action **Delete Expense** Permanently deletes an expense from your Harpoon account. - Action **Delete Invoice** Permanently removes an invoice from Harpoon. Returns Harpoon's confirmation that the invoice was deleted. - Action **Delete Note** Deletes a note from your Harpoon account. - Action **Delete Recurring Expense** Deletes a recurring expense template from Harpoon by its id, so it stops generating new expenses. - Action **Delete Recurring Invoice** Stops and removes a recurring invoice schedule in Harpoon so it no longer generates invoices. Returns Harpoon's confirmation that it was deleted. - Action **Delete Time Entry** Deletes a time entry from your Harpoon account. - Action **Get Client** Returns a single client from your Harpoon account, including its name, contact details and other stored attributes. - Action **Get Client Credits** Returns a client's credit entries in Harpoon, along with the credit still available on the account. - Action **Get Contact** Returns a single Harpoon contact, including their name, email address, phone number, and the client they belong to. - Action **Get Estimate** Returns a single estimate from your Harpoon account, including its client, line items, totals and status. - Action **Get Expense** Returns a single expense from your Harpoon account, including its amount, date, vendor, category and the client or project it is attached to. - Action **Get Expense Category** Returns a single Harpoon expense category with every detail it carries, including its name and budget settings. - Action **Get Invoice** Fetches one invoice from Harpoon by its id, with its client, line items and payment totals. An error occurs if the invoice is not found. - Action **Get Lead Source** Returns a single lead source from your Harpoon account. - Action **Get Project** Returns a single project from your Harpoon account, including its client, budget and status. - Action **Get Recurring Expense** Fetches one recurring expense template from Harpoon by its id, with its vendor, amount, frequency and schedule. An error occurs if it is not found. - Action **Get Recurring Invoice** Returns a single recurring invoice schedule from Harpoon, including its client, frequency, dates, and line items. - Action **Get Task** Returns a single task category from your Harpoon account, including its name and hourly rate. - Action **Get Team** Returns a single team from your Harpoon account, including its name, email address, phone, address, owner and whether it is active. - Action **Get Time Entry** Returns a single tracked time entry from your Harpoon account, including its date, hours, client, project and notes. - Action **List Contacts** Returns the contacts in your Harpoon account, including each contact's name, email address and phone number. - Action **List Estimates** Returns the estimates in a Harpoon account, optionally narrowed to a year, client, project, status, or search text. - Action **List Expense Categories** Returns the expense categories set up in Harpoon, each with its budget settings. - Action **List Expenses** Returns the expenses in your Harpoon account, optionally narrowed by date range, client, project, category, billing status or search text. - Action **List Invoices** Returns the invoices in your Harpoon account, optionally narrowed by year, client, project, status or a search term. - Action **List Projects** Returns the projects in a Harpoon account, with their client, budget, rate, and dates. - Action **List Teams** Returns the teams in your Harpoon account, along with the total number of teams found. - Action **List Time Entries** Returns time entries from your Harpoon account — either the timers running now or logged history for a date range — optionally narrowed by client, project, task, team member or billing status. - Action **Update Expense** Updates an existing expense in your Harpoon account. Only the values you supply are changed. - Action **Update Invoice** Updates an existing invoice in your Harpoon account. Only the values you supply are changed. - Action **Update Project** Updates an existing project in Harpoon — its name, client, billing type, status, dates, budget and task rates. Returns the updated project. - Action **Update Recurring Expense** Updates a recurring expense in Harpoon — its vendor, amount, frequency, category, dates, and status. Anything left blank keeps its current value. Returns the updated recurring expense. - Action **Update Recurring Invoice** Updates an existing recurring invoice template in your Harpoon account. Only the values you supply are changed. - Action **Update Time Entry** Updates an existing time entry in Harpoon — its date, hours, description, project, task or billing state. - Trigger **New Group** Triggered when a new subscriber group is created in MailerLite. - Action **Add Subscriber to Group** Adds a subscriber to a MailerLite group, creating the subscriber if they do not exist yet. - Action **Create Campaign** Creates a new regular or A/B email campaign addressed to the chosen groups or segments. Its HTML content is added afterwards. - Action **Create Group** Creates a new subscriber group in the MailerLite account and returns the created group. - Action **Delete Campaign** Deletes a campaign from the MailerLite account. A scheduled campaign cannot be deleted until it has been cancelled. - Action **Delete Group** Deletes a subscriber group from the MailerLite account. - Action **Find Group by Name** Returns the subscriber groups that match the specified group name. - Action **Get Group** Returns one subscriber group by its id, including its name, subscriber counts, email activity totals and dates. - Action **List Campaigns** Returns the campaigns in your MailerLite account with the chosen status, with a basic summary and open and click stats for each campaign. - Action **List Groups** Returns the subscriber groups in the MailerLite account, with each group's subscriber counts, email stats and created and updated dates. - Action **List Segments** Returns the segments stored in your MailerLite account, with each segment's title, rules, subscriber count and email engagement totals. - Action **List Subscriber Groups** Returns the groups a subscriber belongs to, with each group's subscriber counts and sent, opened and clicked totals. - Action **List Subscribers** Returns the subscribers in the MailerLite account, optionally limited to one status such as active or unsubscribed. - Action **Remove Subscriber From a Group** Removes a subscriber from a group, identified by the subscriber's id or email address. The subscriber stays in the account and in any other groups. - Action **Search Subscribers** Returns the subscribers in your MailerLite account that match a search term, such as an email address or name. - Action **Send Campaign** Sends a draft campaign immediately or schedules it for a later time, and returns the campaign with its status and emails. - Action **Set Campaign Content** Sets the HTML and plain-text content of a draft campaign, replacing what the campaign's email contains. - Action **Unsubscribe Subscriber** Marks a subscriber as unsubscribed across the MailerLite account and returns the updated subscriber. Their name and fields can be updated in the same step. - Action **Update Group** Renames an existing subscriber group and returns the updated group with its subscriber and email counts. ## Each app on its own - [ **Harpoon** Harpoon is a financial planning, scheduling, time-tracking, invoicing, and budgeting platform for...](https://apiant.ai/connections/harpoon) - [ **MailerLite Classic** Use MailerLite Classic to stay connected with your customers through email marketing.](https://apiant.ai/connections/mailerlite-classic) Reviews ## What our customers say ## More from Harpoon - [ **Harpoon to Bugcrowd** Bugcrowd API for interacting and tracking the reported issues programmatically](https://apiant.ai/connect/harpoon-to-bugcrowd) - [ **Harpoon to HubSpot** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/harpoon-to-hubspot) - [ **Harpoon to Salesforce** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/harpoon-to-salesforce) - [ **Harpoon to Slack** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/harpoon-to-slack) - [ **Harpoon to Google Sheets** Google Sheets is Google's online spreadsheet app for creating, editing and sharing spreadsheets.](https://apiant.ai/connect/harpoon-to-google-sheets) - [ **Harpoon to Gmail** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/harpoon-to-gmail) ## More into MailerLite Classic - [ **HubSpot to MailerLite Classic** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/hubspot-to-mailerlite-classic) - [ **Google Sheets to MailerLite Classic** Google Sheets is Google's online spreadsheet app for creating, editing and sharing spreadsheets.](https://apiant.ai/connect/google-sheets-to-mailerlite-classic) - [ **Gmail to MailerLite Classic** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/gmail-to-mailerlite-classic) - [ **Google Calendar to MailerLite Classic** Google Calendar is a time management tool providing scheduling features, event reminders, and integration...](https://apiant.ai/connect/google-calendar-to-mailerlite-classic) - [ **Google Drive to MailerLite Classic** Google Drive is a cloud storage solution for uploading, sharing, and collaborating on files across devices...](https://apiant.ai/connect/google-drive-to-mailerlite-classic) - [ **Mailchimp to MailerLite Classic** Mailchimp marketing automation and email platform.](https://apiant.ai/connect/mailchimp-to-mailerlite-classic) Questions ## Harpoon and MailerLite Classic, answered ### ### What can start an automation from Harpoon? Any of Harpoon's 9 triggers in the catalog, including New Client, New Contact, New Expense and New Expense Category. Describe the moment in plain language and your agent picks the right one. ### ### What can your agent do in MailerLite Classic when something happens in Harpoon? Any of MailerLite Classic's 18 actions, including Create Campaign, Create Group, Send Campaign and Update Group. Your agent maps the data both ways and tests every scenario before it ships. ### ### Can it also run from MailerLite Classic to Harpoon? Yes. When something happens in MailerLite Classic, your agent can act in Harpoon too. This page covers both directions: MailerLite Classic's triggers and Harpoon's actions are listed here as well. ### ### Do I have to build a connector for Harpoon or MailerLite Classic? No. Both are in the catalog with their triggers and actions. You describe the automation; your agent builds it, tests every scenario and keeps it running. ### ### Can my AI client use Harpoon and MailerLite Classic without building an automation? Yes. With your AI client connected to APIANT, ask it to do something in either app once and it runs that action on the spot. Ask for an automation and your agent builds it, tests every scenario and keeps it running. One connection covers both. ### ### What happens when something fails? Your agent works that out for you. It plans the failure paths along with the happy path, then tests every scenario before it ships. ### ### Is there a free plan? Yes. Every plan includes the agent, including free, and building from your own AI client spends no assistant credits.