generate a list of field names for a feature class, with datatype and length

list_fields.py

import arcpy, os

fc = os.path.join(r"path",r"to",r"your",r"featureclass")
field_list = [[field.name,field.type,str(field.length)] for field in arcpy.ListFields(fc)]
for field in field_list:
    print(','.join(field))

made my example feature class path match how it should be entered.