--- title: "Connect Affinity to Lettr - APIANT.ai" description: "When \"New List\" fires in Affinity, 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/affinity-to-lettr" --- # Connect Affinity to Lettr When **New List** fires in [Affinity](https://apiant.ai/connections/affinity), 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. Affinity **6** triggers Affinity **17** 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 Affinity 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 Affinity can start in Lettr - When **New List** in Affinity then **Add contact** in Lettr - When **New List Entry** in Affinity 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 Affinity and Lettr ## Triggers and actions 6 triggers · 28 actions - Trigger **Field Value Changes** Triggers when a field value is added, updated or removed in Affinity. - Trigger **New List** Triggers when a new list is created in Affinity. - Trigger **New List Entry** Triggers when a new entry is added to an Affinity list. - Trigger **New Opportunity** Triggers when a new opportunity is added in Affinity. - Trigger **New Organization** Triggers when a new organization is added in Affinity. - Trigger **New Person** Triggers when a new person is added in Affinity. - Action **Add field value** Sets the value of a field on a list entry (a row on an Affinity list), such as a status dropdown, number, date, text, person or company field. - Action **Add reminder** Creates a one-time or recurring reminder in Affinity for a person, company or opportunity, assigned to an internal user. - Action **Delete opportunity** Deletes an opportunity in Affinity. - Action **Delete person** Deletes a person from Affinity. Internal people in your organization cannot be deleted. - Action **Find a List Entry** Finds an entry on an Affinity list by the name, email or domain of its person, organization or opportunity. - Action **Find an Organization** Finds Affinity organizations by name or domain and returns the best match. - Action **Find a Person** Finds Affinity persons by name or email address and returns the best match. - Action **Find opportunities** Finds opportunities whose name contains the text you give, returning the first match and all matches. - Action **Get an Opportunity** Returns one Affinity opportunity by ID, with its name and the list it belongs to. - Action **Get an Organization** Returns one Affinity organization (company) by ID, with its name and domains. - Action **Get a Person** Returns one Affinity person by ID, with their name and email addresses. - Action **Get list** Returns a single Affinity list's details: name, entity type, owner, creator, privacy setting and creation date. - Action **List fields** Returns the fields (columns) available on an Affinity list, including custom list and global fields, with their type and value type. - Action **List lists** Returns the lists in your Affinity workspace that you can view, optionally filtered by name. - Action **List notes** Returns notes in Affinity (excluding replies), optionally filtered by id, creator or creation date. - Action **Update field value** Sets the value of a single field on a list entry (row) in an Affinity list, replacing its current value. - Action **Update opportunity** Renames an existing opportunity in Affinity. - 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 - [ **Affinity** Affinity is a collective intelligence CRM, helping you keep track of the people and organizations in your...](https://apiant.ai/connections/affinity) - [ **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 Affinity - [ **Affinity to HubSpot** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/affinity-to-hubspot) - [ **Affinity to Salesforce** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/affinity-to-salesforce) - [ **Affinity to Slack** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/affinity-to-slack) - [ **Affinity to Google Sheets** Google Sheets is Google's online spreadsheet app for creating, editing and sharing spreadsheets.](https://apiant.ai/connect/affinity-to-google-sheets) - [ **Affinity to Gmail** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/affinity-to-gmail) - [ **Affinity to Google Calendar** Google Calendar is a time management tool providing scheduling features, event reminders, and integration...](https://apiant.ai/connect/affinity-to-google-calendar) ## 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 is Google's online spreadsheet app for creating, editing and sharing spreadsheets.](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 ## Affinity and Lettr, answered ### ### What can start an automation from Affinity? Any of Affinity's 6 triggers in the catalog, including New List, New List Entry, New Opportunity and New Organization. Describe the moment in plain language and your agent picks the right one. ### ### What can your agent do in Lettr when something happens in Affinity? 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 Affinity? Lettr has no triggers in the catalog today, so automations start in Affinity. 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 Affinity 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 Affinity 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.