Sync e-commerce contacts and trigger email/SMS automations via the Omnisend API.

Omnisend

Sync e-commerce contacts and trigger email/SMS automations via the Omnisend API.

Omnisend is an email and SMS marketing platform for e-commerce. This tool reads and writes your Omnisend contact list and fires customer events that kick off Omnisend automation flows (welcome series, abandoned cart, post-purchase, etc.).

Base URL: https://api.omnisend.com/api
Auth: Authorization: Omnisend-API-Key <apiKey> plus the required Omnisend-Version: 2026-03-15 header (both sent automatically)
Dependencies: none — Python standard library only (urllib, json)

Operations

operation	method / endpoint	what it does
`list-contacts`	`GET /api/contacts`	List contacts, optionally filtered by `email`, `phone`, `status`, with `limit` (1-250).
`get-contact`	`GET /api/contacts/{id}`	Fetch a single contact by its Omnisend `contactId`.
`create-contact`	`POST /api/contacts`	Create or update a contact from an `email` and/or `phone` identifier.
`send-event`	`POST /api/events`	Send a customer event (`eventName`) that triggers an Omnisend automation.

API key setup

Log in to Omnisend.
Go to Store settings -> Integrations & API -> API keys.
Create an API key and copy it.
Pass it as the apiKey input. It is sent as Authorization: Omnisend-API-Key <apiKey>.

A single API key carries all the scopes the operations need (contacts.read, contacts.write, events.write) — no OAuth flow is required.

Inputs

input	used by	notes
`apiKey`	all	required
`operation`	all	required: one of the four above
`contactId`	`get-contact`	Omnisend contact id
`email`	`create-contact`, `send-event`, `list-contacts`	email identifier / filter
`phone`	`create-contact`, `send-event`, `list-contacts`	phone in international format, e.g. `+15551234567`
`status`	`create-contact`, `list-contacts`	`subscribed` (default), `unsubscribed`, or `nonSubscribed`
`firstName`	`create-contact`	optional
`lastName`	`create-contact`	optional
`tags`	`create-contact`	comma-separated, e.g. `source: api,vip`
`limit`	`list-contacts`	1-250, default 100
`eventName`	`send-event`	the automation trigger name, e.g. `placed order`
`properties`	`send-event`	optional JSON object of event data

Examples

List the 50 most recent contacts

{
  "apiKey": "YOUR-OMNISEND-API-KEY",
  "operation": "list-contacts",
  "limit": "50"
}

Create / subscribe a contact

{
  "apiKey": "YOUR-OMNISEND-API-KEY",
  "operation": "create-contact",
  "email": "[email protected]",
  "firstName": "Jane",
  "status": "subscribed",
  "tags": "source: api"
}

Look up one contact

{
  "apiKey": "YOUR-OMNISEND-API-KEY",
  "operation": "get-contact",
  "contactId": "5f3c0e2b9a1c2d0011223344"
}

Trigger an automation by sending an event

{
  "apiKey": "YOUR-OMNISEND-API-KEY",
  "operation": "send-event",
  "eventName": "placed order",
  "email": "[email protected]",
  "properties": "{\"orderId\":\"1042\",\"total\":49.90}"
}

Output

The tool publishes:

result — the Omnisend response body as a JSON string
status — the HTTP status code (200/201 for contacts, 202 for events)

On error it prints {"error": "..."} and the step fails.