The Offline Event Webhook lets you record an event for a specific visitor in Mida from your own backend or systems — useful when something happens outside the browser that you want to track against a visitor (for example, a server-confirmed signup, a CRM stage change, or an offline action). Recorded events are available as goals or secondary goals in your experiments.

Endpoint

POST https://api-{{region}}.mida.so/abtest/event/webhook

Use the host that matches where your data is hosted:

US: https://api-us.mida.so/abtest/event/webhook
EU: https://api-eu.mida.so/abtest/event/webhook

Requests must be sent with Content-Type: application/json.

User identification

You must provide at least one of the following identifiers so Mida can match the event to a visitor. If mida_uuid is provided, it is used as the sole identifier; email and id are only used when mida_uuid is absent.

Parameter	Type	Required	Description
`mida_uuid`	String	Optional*	The unique identifier generated by Mida. Retrieve it in the browser with `await mida.uuid()`. Alias: `uuid`.
`email`	String	Optional*	The visitor's email address, set via the Mida client-side user attribution API.
`id`	String	Optional*	Your system's user ID, set via the Mida client-side user attribution API.

*At least one of these three must be provided.

Request parameters

Parameter	Type	Required	Description
`project_key`	String	Yes	Your Mida project (public/widget) key. Alias: `mida_project_key`.
`event_name`	String	Yes	The name of the event being recorded (this is how it appears as a goal / secondary goal).
`properties`	Object	No	Additional custom metadata to store with the event.

Request example

{
  "project_key": "YOUR_PROJECT_KEY",
  "event_name": "signup_completed",
  "mida_uuid": "f8cb2ebe-XXXX-4a4f-a967-85a35aca4df9",
  "email": "[email protected]",
  "id": "internal_user_id",
  "properties": {
    "plan": "pro",
    "source": "backend"
  }
}

Response codes

Responses are returned as a plain-text message with the corresponding HTTP status code.

Status code	Response body	Meaning
200	`Event recorded successfully`	The event was recorded for the visitor.
400	`Missing required fields: project_key (or mida_project_key), event_name, and at least one identifier (mida_uuid or uuid, email, or id)`	A required field is missing.
400	`Invalid widget key`	The `project_key` could not be resolved to a project.
400	`Visitor not found`	No visitor matched the identifier(s) provided.
500	`Internal server error`	An unexpected error occurred.

Usage notes

Make sure the Mida script is installed on your site before using this webhook — the visitor must already exist in Mida for the event to be matched.
Get the Mida visitor UUID in the browser with mida.uuid(), for example: const mida_uuid = await mida.uuid();
Find your project key in your Mida dashboard settings.
User identification (email / id) can be set up through the Mida client-side user attribution API.
The properties object is optional and lets you attach additional metadata to the event.
Recorded events can be selected as goals or secondary goals in your experiments.

Example cURL request

curl -X POST https://api-us.mida.so/abtest/event/webhook \
     -H "Content-Type: application/json" \
     -d '{"project_key": "YOUR_PROJECT_KEY", "event_name": "signup_completed", "mida_uuid": "f8cb2ebe-XXXX-4a4f-a967-85a35aca4df9", "properties": {"plan": "pro", "source": "backend"}}'

Offline Event Webhook (Client-side)