attributes
The Amazon Connect attributes. These attributes can be accessed in flows just like any other contact attributes.
You can have up to 32,768 UTF-8 bytes across all attributes for a contact. Attribute keys can include only alphanumeric, dash, and underscore characters.
In the Set contact attributes block, when the attributes for a contact exceed 32 KB, the contact is routed down the Error branch of the flow. As a mitigation, consider the following options:
- Remove unnecessary attributes by setting their values to empty. 
- If the attributes are only used in one flow and don't need to be referred to outside of that flow (for example, by a Lambda or another flow), then use flow attributes. This way you aren't needlessly persisting the 32 KB of information from one flow to another. For more information, see Flow block: Set contact attributes in the Amazon Connect Administrator Guide.