---
title: "Connect Mailrelay to Shift4 - APIANT.ai"
description: "When \"New subscriber\" fires in Mailrelay, your agent runs \"Add customer\" in Shift4."
canonical: "https://apiant.ai/connect/mailrelay-to-shift4"
---

# Connect Mailrelay to Shift4

When **New subscriber** fires in [Mailrelay](https://apiant.ai/connections/mailrelay), your agent runs **Add customer** in [Shift4](https://apiant.ai/connections/shift4). Describe the whole flow and it is built, tested on every scenario and kept running.

Mailrelay **1** trigger Mailrelay **11** actions Shift4 **21** actions

What the catalog holds today. Ask for anything missing and your agent reads the API documentation and adds it.

## What do you want Mailrelay and Shift4 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 Mailrelay can start in Shift4

- When **New subscriber** in Mailrelay then **Add customer** in Shift4
- When **New subscriber** in Mailrelay then **Update customer** in Shift4

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 Mailrelay and Shift4

## Triggers and actions 1 trigger · 32 actions

- Trigger

**New subscriber**

Polling trigger for newly created subscribers.

- Action

**Add campaign**

Create a campaign.

- Action

**Add group**

Create a group.

- Action

**Add subscriber**

Create a subscriber.

- Action

**Delete subscriber**

Remove a subscriber.

- Action

**Find subscribers by criteria**

Search subscribers using q[field_predicate] filters.

- Action

**Get campaign**

Get a campaign by id.

- Action

**Get subscriber**

Get a subscriber by id.

- Action

**List campaigns**

List campaigns.

- Action

**List groups**

List groups.

- Action

**List senders**

List senders.

- Action

**Update subscriber**

Update a subscriber.

- Action

**Add card**

Saves a credit or debit card to an existing Shift4 customer, either from a card token / successful charge, or from full card details.

- Action

**Add charge**

Creates a new charge to a customer or card.

- Action

**Add customer**

Creates a new customer in Shift4, optionally saving a card to them as their default card.

- Action

**Add plan**

Creates a new subscription plan that customers can be subscribed to.

- Action

**Add refund**

Refunds an existing charge in full or in part, returning the funds to the card that was charged.

- Action

**Add subscription**

Creates a subscription that bills a customer automatically according to a plan.

- Action

**Delete card**

Deletes a saved card from a Shift4 customer. If the deleted card was the customer's default, the most recently added card becomes the new default.

- Action

**Delete customer**

Deletes an existing Shift4 customer.

- Action

**Delete plan**

Deletes a plan by ID.

- Action

**Delete subscription**

Cancels/deletes an existing subscription by ID.

- Action

**Get charge**

Fetches a charge by ID.

- Action

**Get customer**

Fetches a customer by ID.

- Action

**Get dispute**

Fetches a dispute by ID.

- Action

**Get plan**

Fetches a plan by ID.

- Action

**Get refund**

Retrieves an existing Shift4 refund by its id.

- Action

**Get subscription**

Fetches a subscription by ID.

- Action

**List cards**

Lists the saved cards of a Shift4 customer, most recently created first.

- Action

**List refunds**

Returns all refunds.

- Action

**Update charge**

Updates an existing Shift4 charge's customer, description, shipping, billing, fraud status or metadata. Fields left blank are unchanged.

- Action

**Update customer**

Updates an existing Shift4 customer. Any field left blank is left unchanged.

- Action

**Update subscription**

Updates an existing subscription. Any field left blank is left unchanged.

## Each app on its own

- [ **Mailrelay** Mailrelay is an advanced email marketing platform with powerful features.](https://apiant.ai/connections/mailrelay)
- [ **Shift4** Payment processing platform with a REST API for card and alternative payment transactions across e-commerce...](https://apiant.ai/connections/shift4)

Reviews

## What our customers say

## More from Mailrelay

- [ **Mailrelay to Salesforce** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/mailrelay-to-salesforce)
- [ **Mailrelay to Slack** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/mailrelay-to-slack)
- [ **Mailrelay to Stripe** Stripe is a payment processing platform for online businesses.](https://apiant.ai/connect/mailrelay-to-stripe)
- [ **Mailrelay to Shopify** Shopify is a commerce platform for online stores and retail point-of-sale.](https://apiant.ai/connect/mailrelay-to-shopify)
- [ **Mailrelay to QuickBooks Online** QuickBooks Online accounting — manage customers, invoices, bills, payments, vendors, expenses, and more via...](https://apiant.ai/connect/mailrelay-to-quickbooks-online)
- [ **Mailrelay to Pipedrive** Pipedrive is a sales CRM and pipeline management tool.](https://apiant.ai/connect/mailrelay-to-pipedrive)

## More into Shift4

- [ **Instagram to Shift4** Instagram is a social media platform for sharing photos, videos, and stories.](https://apiant.ai/connect/instagram-to-shift4)
- [ **HubSpot to Shift4** HubSpot is your all-in-one stop for all of your marketing software needs.](https://apiant.ai/connect/hubspot-to-shift4)
- [ **Salesforce to Shift4** Salesforce is a leading enterprise customer relationship management (CRM) platform.](https://apiant.ai/connect/salesforce-to-shift4)
- [ **Slack to Shift4** Slack is a messaging platform for teams. Post messages, manage channels, users, reminders, and react to...](https://apiant.ai/connect/slack-to-shift4)
- [ **Google Sheets to Shift4** Google Sheets](https://apiant.ai/connect/google-sheets-to-shift4)
- [ **Gmail to Shift4** Gmail is Google’s email service, featuring spam protection, search functions, and seamless integration with...](https://apiant.ai/connect/gmail-to-shift4)

Questions

## Mailrelay and Shift4, answered

###

### What can start an automation from Mailrelay?

Any of Mailrelay's 1 trigger in the catalog, including New subscriber. Describe the moment in plain language and your agent picks the right one.

###

### What can your agent do in Shift4 when something happens in Mailrelay?

Any of Shift4's 21 actions, including Update charge, Update customer, Update subscription and Add card. Your agent maps the data both ways and tests every scenario before it ships.

###

### Can it also run from Shift4 to Mailrelay?

Shift4 has no triggers in the catalog today, so automations start in Mailrelay. If you need the other direction, ask: your agent reads Shift4's API documentation and adds it.

###

### Do I have to build a connector for Mailrelay or Shift4?

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 Mailrelay and Shift4 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.
