# Exists Check

**Exists Check** node is designed to verify the existence of any value accessible through [Magical Autocomplete](/flow-builder/cql-cosmocloud-query-language/magical-autocomplete.md) within the current flow. This node can check for the existence of node data, variables, token data, custom secrets, and more, providing a boolean result that can be used for conditional logic in your workflow.

### Properties Panel

| **Field**              | **Description**                                                                      | **Required** |
| ---------------------- | ------------------------------------------------------------------------------------ | ------------ |
| Node name              | [Node Name](https://docs.cosmocloud.io/concepts-and-in-depth/flow-builder/node-name) | true         |
| CQL reference to check | The CQL reference to the value being checked for existence.                          | true         |

### Usage

1. Specify the CQL reference of the value you want to check for existence.
2. The node will return a boolean value indicating whether the referenced item exists.

### Behaviour

* The node evaluates the provided CQL reference within the current flow context.
* If the referenced item exists, the node returns `true`.
* If the referenced item does not exist, the node returns `false`.
* The result can be used in subsequent nodes for conditional branching or decision making.

### Returns

The node returns a boolean value:

* `true` if the referenced item exists
* `false` if the referenced item does not exist

You can access this result using Magical Autocomplete (e.g., `$.<node_name>.result`) in any node below this node.

### Example

Let's say you want to check if a variable named `user_id` exists in the current flow:

1. Set CQL Reference to `$.variables.user_id`

If `user_id` exists in the flow, the node will return `true`. If it doesn't exist, it will return `false`.

### Best Practices

* Use this node to validate the presence of data before attempting to use it in your flow.


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