--- title: "Connect Saasu to Lettr - APIANT.ai" description: "When \"New Contact\" fires in Saasu, your agent runs \"Add contact\" in Lettr. Describe the whole flow and it is built, tested on every scenario and kept running." canonical: "https://apiant.ai/connect/saasu-to-lettr" --- # Connect Saasu to Lettr When **New Contact** fires in [Saasu](https://apiant.ai/connections/saasu), your agent runs **Add contact** in [Lettr](https://apiant.ai/connections/lettr). Describe the whole flow and it is built, tested on every scenario and kept running. Saasu **1** trigger Saasu **21** actions Lettr **11** actions What the catalog holds today. Ask for anything missing and your agent reads the API documentation and adds it. ## What do you want Saasu and Lettr 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 Saasu can start in Lettr - When **New Contact** in Saasu then **Add contact** in Lettr - When **New Contact** in Saasu then **Add contact to list** in Lettr 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 Saasu and Lettr ## Triggers and actions 1 trigger · 32 actions - Trigger **New Contact** Triggers when a new contact is added to your Saasu file. - Action **Add activity** Creates an activity (task, call, meeting, note) in your Saasu file, optionally attached to a contact or transaction. - Action **Add company** Creates a company record in Saasu. - Action **Add item** Creates an inventory or combo item in Saasu. - Action **Add journal** Creates a manual journal entry with debit and credit lines in a Saasu file. - Action **Create Contact** Creates a new contact (person) in your Saasu file and returns its id. - Action **Create Item Invoice** Creates an item-layout invoice, quote or order in Saasu with inventory item line items. - Action **Create Service Invoice** Creates a service-layout sale or purchase invoice in Saasu, with line items described by account and amount. - Action **Delete contact** Deletes a contact from your Saasu file. - Action **Delete invoice** Deletes a sale or purchase invoice from the Saasu file. - Action **Delete item** Deletes an inventory item from the Saasu file. - Action **Email invoice** Emails a Saasu invoice to the email address you specify. - Action **Find accounts** Returns the accounts in your Saasu chart of accounts, filtered by type, status, bank-account flag or header account. - Action **Find companies** Returns the companies in your Saasu file whose name matches, optionally limited to a last-modified date range. - Action **Find Contact** Finds Saasu contacts matching an email, name, company or other criteria and returns the matching contacts. - Action **Find items** Returns the inventory and combo items whose code or description matches the search text. - Action **Get contact** Returns a single Saasu contact by its ID. - Action **Get invoice** Returns a single Saasu invoice (sale or purchase) by its ID, including line items and totals. - Action **Get journal** Returns a single journal transaction, including its date, reference, summary and journal line items. - Action **Update contact** Updates an existing contact in Saasu, such as their name, email, phone numbers, addresses and customer/supplier flags. - Action **Update invoice** Updates an existing Saasu sale or purchase invoice, replacing its details and line items. - Action **Update item** Updates an existing inventory or combo item in Saasu, such as its code, description, prices, accounts and tax codes. - Action **Add audience list** Creates a new audience list in Lettr with the given name and returns the created list. - Action **Add contact** Adds a new contact to your Lettr audience, optionally placing it on a list, setting custom properties, and sending a double opt-in confirmation email. - Action **Add contact to list** Adds an existing contact to one of your audience lists. Succeeds whether the contact was newly added or was already on the list. - Action **Add template** Creates a new email template in Lettr from HTML or Topol editor JSON content, and publishes its first version with the merge tags found in the content. - Action **Delete contact** Permanently deletes a contact from your Lettr audience. - Action **Get contact** Returns a single audience contact, including its subscription status, custom properties, lists and topics. - Action **Get template** Returns a single email template by its slug, including its HTML, editor content, purpose, status and version details. - Action **List audience lists** Returns all audience lists in your Lettr team, with each list's name and contact count. - Action **List contacts** Returns the contacts in your Lettr audience, optionally narrowed by a search term, subscription status, list or segment. - Action **List templates** Returns the email templates in a Lettr project, optionally limited to one folder or to transactional or campaign templates. - Action **Update contact** Updates an existing contact in your Lettr audience, changing its email address, subscription status or custom properties. Fields left blank are not changed. ## Each app on its own - [ **Saasu** Fast, simple online accounting for small business that includes cashflow, invoicing, inventory, payroll and...](https://apiant.ai/connections/saasu) - [ **Lettr** Lettr is a email API for artisans, send transactional emails using HTML or stored templates.](https://apiant.ai/connections/lettr) Reviews ## What our customers say ## More from Saasu - [ **Saasu to Salesforce** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/saasu-to-salesforce) - [ **Saasu to Slack** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/saasu-to-slack) - [ **Saasu to Stripe** Stripe is a payment processing platform for online businesses.](https://apiant.ai/connect/saasu-to-stripe) - [ **Saasu to Shopify** Shopify is a commerce platform for online stores and retail point-of-sale.](https://apiant.ai/connect/saasu-to-shopify) - [ **Saasu to Trello** Trello is a visual collaboration tool that organizes projects into boards, lists, and cards.](https://apiant.ai/connect/saasu-to-trello) - [ **Saasu to Zoom** Zoom unifies cloud video conferencing, simple online meetings, group messaging, and a software-based...](https://apiant.ai/connect/saasu-to-zoom) ## More into Lettr - [ **HubSpot to Lettr** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/hubspot-to-lettr) - [ **Salesforce to Lettr** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/salesforce-to-lettr) - [ **Slack to Lettr** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/slack-to-lettr) - [ **Google Sheets to Lettr** Google Sheets](https://apiant.ai/connect/google-sheets-to-lettr) - [ **Gmail to Lettr** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/gmail-to-lettr) - [ **Google Calendar to Lettr** Google Calendar is a time management tool providing scheduling features, event reminders, and integration...](https://apiant.ai/connect/google-calendar-to-lettr) Questions ## Saasu and Lettr, answered ### ### What can start an automation from Saasu? Any of Saasu's 1 trigger in the catalog, including New Contact. Describe the moment in plain language and your agent picks the right one. ### ### What can your agent do in Lettr when something happens in Saasu? Any of Lettr's 11 actions, including Update contact, Add audience list, Add contact and Add contact to list. Your agent maps the data both ways and tests every scenario before it ships. ### ### Can it also run from Lettr to Saasu? Lettr has no triggers in the catalog today, so automations start in Saasu. If you need the other direction, ask: your agent reads Lettr's API documentation and adds it. ### ### Do I have to build a connector for Saasu or Lettr? 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 Saasu and Lettr 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.