When dealing with a large array or string, this error is returned and the next node fails to process the data.
As a string, the size of the string is 21,417KB. There is no other data being passed from the node. The docs mention 32MB several places as the max allowable size to pass between nodes.
Ran a few tests to determine if the error was due to size or a special character.
Reducing the string to 16,260KB still failed with the same error.
Reducing the string to 10,397KB succeeded.
Setting the string to the difference between 16MB and 10MB succeeded. So this does appear to be a size limitation issue, not a special character issue. The size limitation is unexpected considering the aforementioned documentation.