# Create Custom Discovery Rules

Build your own discovery rules from domain filters, add tags and auto approval, and edit, pause or delete them.

Source: https://docs.deepinfo.com/guide/easm/custom-discovery-rules/

Last updated: 2026-09-26

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A custom discovery rule describes domains you want discovery to find, using filters on their WHOIS, DNS, SSL
and website data or on their names. The filters select which domains in Deepinfo's dataset become candidates.
What a rule finds appears in the [Discovery](/guide/easm/discovery/) review list, with the rule's name on its
badge.

## Before You Start

- **Package:** External Attack Surface Management (EASM).
- **Role:** Admin or Member.
- For the rules Deepinfo runs for you, see [Tune smart discovery](/guide/easm/discovery-settings/).

## Where to Find It

**Sidebar:** **EXTERNAL ATTACK SURFACE MANAGEMENT** › **ASSETS** › **DISCOVERY** · **Tab:** **SETTINGS** · [https://platform.deepinfo.com/app/easm/discoveries/settings/custom-rules](https://platform.deepinfo.com/app/easm/discoveries/settings/custom-rules)

On the **SETTINGS** tab, select **Custom Rules** in the menu on the left.

## Read the Screen

![Custom Rules with the header, the rules table and one expanded rule showing its filters, tags and Auto Approval, numbered 1 to 3.](/img/guide/easm/custom-discovery-rules-01.png)

1. **Header:** the number of custom rules and **CREATE RULE +**.
2. **The rules table:**

   | Column | What it shows |
   |---|---|
   | **STATUS** | A switch, and whether the rule is active |
   | **RULE NAME** | The rule's name |
   | **DISCOVERED ASSETS** | How many assets the rule has discovered |
   | **CREATE DATE** | When the rule was created |
   | **LAST UPDATE DATE** | When it was last changed |
   | (chevron) | Expands the rule |

3. **An expanded rule** shows:
   - **FILTERS**, each written as rule · category · field · operator · value, for example
     **MUST** · **Webdata** · **HTTP** · **Final Domain** · **EQUAL** · a domain name;
   - **TAGS**;
   - the **Auto Approval** switch;
   - **EDIT THIS RULE** and **DELETE THIS RULE**.

## Create a Rule

1. Select **CREATE RULE +**. The **Custom Rules** dialog opens.
2. Enter a **RULE NAME**. You will see it on the rule badges in the Discovery lists.
3. Optional: choose **TAGS** from **Select**, or type a new tag.
4. Set **AUTO APPROVAL**. It is **Disabled** by default: what the rule finds waits for your review. With
   **Enabled**, what it finds is added to your inventory directly.
5. Set **STATUS**. It is **Active** by default.
6. Add at least one filter. Select a category chip: **Domain Type**, **Whois**, **DNS**, **SSL**, **Webdata**,
   **Domain Name**, **Extension** or **Subdomain**. In the popover:
   1. Pick the field, then the rule (**Must**, for example), the operator (**Equal**, for example) and the
      **Value**.
   2. Select **Add New** to add another condition, or **Clear All** to start over.
   3. Select **APPLY**.

   **Domain Type** takes **Only Domain** or **Only Subdomain**.
7. Select **CREATE**. It becomes available once the rule has a name and at least one filter.

![The Custom Rules dialog with the Webdata filter chip open on its Select field popover.](/img/guide/easm/custom-discovery-rules-02.png)

The rules **Must**, **Must Not** and **Should** work as in the API; see
[Search & filters](/getting-started/search-and-filters/) and
[Search, filter and export lists](/guide/basics/lists-filters-and-exports/).

> [!CAUTION]
> With **AUTO APPROVAL** enabled, the assets the rule finds go straight into your inventory, and an approval
> cannot be undone from Discovery. Start with auto approval off, check what the rule finds in Discovery, and
> turn it on once the results look right.

## Change, Pause or Delete a Rule

Expand the rule first.

- **Change it:** select **EDIT THIS RULE**. The same dialog opens with your settings. Change them and select
  **UPDATE**.
- **Pause it:** turn off its **STATUS** switch and confirm. Turn it on again the same way.
- **Turn auto approval on or off:** select the **Auto Approval** switch and confirm.
- **Delete it:** select **DELETE THIS RULE**. The **Delete Rule** confirmation names the rule. Select **DELETE**.

## Good to Know

- A rule name can be long; the table may shorten it. Expand the rule to see its filters.
- A rule has up to 10 tags.
- To keep specific assets out of discovery whatever your rules find, use the **Ignored Assets** list; see
  [Tune smart discovery](/guide/easm/discovery-settings/).

## Do This With the API

- List your custom rules: [Asset Discovery Custom Discovery Rule Search](/reference/easm/asset-discovery-custom-discovery-rule-search/)
- Create a rule: [Asset Discovery Custom Discovery Rule Create](/reference/easm/asset-discovery-custom-discovery-rule-create/)
- Change a rule: [Asset Discovery Custom Discovery Rule Update](/reference/easm/asset-discovery-custom-discovery-rule-update/)
- Delete a rule: [Asset Discovery Custom Discovery Rule Delete](/reference/easm/asset-discovery-custom-discovery-rule-delete/)