> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cognigy.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Regex Slot Filler

<Frame>
  <img class="image-center" src="https://mintcdn.com/cognigy-15abf2ba/OU10XTKbB-9IwiZJ/_assets/ai/develop/node-reference/ai/regex-slot-filler.png?fit=max&auto=format&n=OU10XTKbB-9IwiZJ&q=85&s=3dcb5ad002a971d5ea884c767875bab4" alt="Regex Slot Filler Node configuration panel" style={{ width: 'auto' }} width="462" height="124" data-path="_assets/ai/develop/node-reference/ai/regex-slot-filler.png" />
</Frame>

## Description

Use this Node to fill Slots using regular expressions. To learn more about Slots and Tags, see [Lexicons & Slots](/ai/platform-features/nlu/slots/user-defined/lexicon).

## Parameters

| Parameter | Type                                                | Description                                                                                                                                                                                                                                                                                                  |
| --------- | --------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Regex     | Regular expression                                  | The regular expression applied to the user input. The regular expression must start and end with /, for example, `/^1\d{7}$/`. Compared to [regular expressions](/ai/platform-features/nlu/slots/user-defined/regex) in **Slot Fillers** on the **NLU** tab, the Regex Slot Filler Node also supports flags. |
| Flags     | Regular expression flag characters in single string | Regular expression flags you want to set. When the `g` flag is used, for example, `/^1\d{7}$/g`, and the input contains multiple matches, all matched values are stored as an array. The array is stored under the `slots` key in the Input object.                                                          |
| Tag       | CognigyScript                                       | The Tag or Slot you want to fill.                                                                                                                                                                                                                                                                            |