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

# UpsertUserDefinedMessage

> Create, update, or delete a user-defined message by message_key.



## Related topics

- [upsertUserDefinedMessage](/api-reference/mutations/upsertUserDefinedMessage.md)
- [UpsertUserDefinedMessageInput](/api-reference/types/UpsertUserDefinedMessageInput.md)
- [UserDefinedMessage](/api-reference/types/UserDefinedMessage.md)
- [userDefinedMessage](/api-reference/queries/userDefinedMessage.md)
- [userDefinedMessages](/api-reference/queries/userDefinedMessages.md)