I asked the AI chat a question from the help files today of how "What token calculator function can I use to remove all characters over 255 characters in a token?" It told me to use the SUBSTRING function. I didn't see it in the list of available functions with that activity. I decided to go ahead and type it in and it did not give me an error, it did error when I didn't have the syntax correct, but after I corrected it was fine. I then clicked on Test Formula and it says, "Function Not in Library...".

Is SUBSTRING not a function in Workflow?