> For the complete documentation index, see [llms.txt](https://docs.omnidesk.io/omnidesk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.omnidesk.io/omnidesk/link-customer/customer-lookup.md).

# Customer lookup

## Get the timeline of a customer.

<mark style="color:blue;">`GET`</mark> `https://account.omnidesk.com/api/v2/customer/timelineByCustomerExternalID`

Retrieve a customer's timeline via the external customer ID. This endpoint returns an array containing a timeline of the contact that occurred with the customer.

#### Query Parameters

| Name                                           | Type    | Description                              |
| ---------------------------------------------- | ------- | ---------------------------------------- |
| brand\_id<mark style="color:red;">\*</mark>    | Integer | Brand ID to which the customer is linked |
| external\_id<mark style="color:red;">\*</mark> | String  | External CRM id of the customer.         |

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