> For the complete documentation index, see [llms.txt](https://docs.reo.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.reo.dev/integrations/input-sources/api-based-integration/lists-api.md).

# Lists API

Custom Lists in Reo.Dev allows Sales and Marketing teams to import, enrich, and segment accounts or developers using a CSV upload. But what if your data changes frequently, or you want to add new entries dynamically, without uploading a new file every time?

That’s where the **Lists API** comes in.

***

### Why Use the Lists API?

Unlike the CSV upload in the UI, which replaces the entire list, the **Lists API lets you add new accounts or developers to an existing list**—without starting from scratch.

**Key Advantage**:

* **Continuously update your lists** with new data.
* Avoid re-uploading or overwriting lists.

**Developer Docs:** <https://developers.reo.dev/#tag/List>

***

#### Where to Get Your API Key

To use the Lists API, your dev team will need a **Product Usage API Key**.

**Steps to find the API Key:**

1. Go to **Settings →Configurations**
2. Click **Configure** under the **API Keys** section.

{% hint style="info" %}
Note: Only users with Admin Role in Reo.Dev can access the API Keys
{% endhint %}

<figure><img src="/files/PvVs0i8SVxSfJsYETEQ3" alt=""><figcaption></figcaption></figure>

3. Copy the key under **Product Usage API**.

<figure><img src="/files/xkA4U6WZur5Jgic5dQJY" alt=""><figcaption></figcaption></figure>

***

### What the API Can Do

The Lists API supports 3 main actions:

| **Action**        | **Description**                                                     |
| ----------------- | ------------------------------------------------------------------- |
| **Create a List** | Set up a new Account or Developer list, define custom columns       |
| **Get All Lists** | Retrieve all existing lists created via API                         |
| **Add to List**   | Append new accounts or developers to a list (key advantage over UI) |

***

#### Share This With Your Tech Team

If you'd like to start using the Lists API to keep your account or developer lists always up-to-date, here’s the full API documentation:

> **🔗 Developer Docs:** <https://developers.reo.dev/#tag/List>

Share this link with your developer team or RevOps engineer to explore implementation.


---

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