NetLogo 7.0.0-beta2:

table:from-json

table:from-json string

Reads in the JSON object from the given string argument, converts it to a table, and reports the table.
The JSON object in the argument must be an object, not an array (i.e. the outmost characters must be `{` and `}`, not `[` and `]`),
but there can be arrays inside the JSON object which will be converted to NetLogo lists.

Take me to the full Table Extension Dictionary