# How to Use Expression Editor

1\. Opening the Expression Editor

* Access the Expression Editor for any node via its settings. Change the input field format to "expression" in the settings. Clicking the blue field will open the Expression Editor. 
* In the ChatGPT node within Messages, click the \`#\` symbol in the lower Message field. This will open the Expression Editor to retrieve data from other nodes.

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2\. Adding a Variable in the Expression Editor

1. On the left, you’ll see a list of nodes, and on the right, an empty expression field.
2. &#x20;Click the required node in the list to see its output data.&#x20;
3. Variables can be multi-level structures, depending on the tool you are interacting with. For instance, the Whisper Diarisation tool that transcribes an audio file and splits it among speakers, displays a complex data structure. It’s first level includes fields like language and speaker count, followed by a collapsible array of segments containing timecodes, speaker info, speech text, and individual word objects.
4. To add a variable, find it in the list and drag it to the expression field in the Expression Editor. Data is transferred in double curly brackets format, usually like: \`{{context\["Node ID"]\["variable name"]}}\`. For instance, to get the task from a start node: \`{{context\["7rwO-start"]\["task"]}}\`

Dragging complex structures into the Expression Editor will show all nested levels.

3\. If the Required Variable is Not Listed:

* &#x20;Variables appear in the list only after the node is executed.&#x20;
* If you add a new field to a node, execute the node to update the fields list in the Expression Editor. The new field value will then be available in the list.


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