Empty response from the webhook

[Karun23]

I created an api and added as callback in "script Includes" for user_criteria table (update, delete, insert) and added in business rule. Receiving the empty response in both current, previous state of script. The follwing is the webhook response for the rule added.

{

"userCriteria": {

"sys_meta": {

"active": "1",

"array": "0",

"attributes": "update_synch=true",

"audit": "0",

"calculation": "",

"choice": "0",

"choice_field": "",

"choice_table": "",

"create_roles": "",

"default_value": "",

"delete_roles": "",

"dependent": "",

"dependent_on_field": "",

"display": "name",

"dynamic_creation": "0",

"dynamic_creation_script": "",

"dynamic_default_value": "",

"dynamic_ref_qual": "",

"element_reference": "0",

"filterable": "1",

"foreign_database": "",

"function_definition": "",

"function_field": "0",

"groupable": "1",

"help": "",

"hint": "",

"i18n_sortable": "1",

"internal_type": "collection",

"label": "User Criteria",

"language": "en",

"mandatory": "0",

"matchable": "1",

"max_length": "40",

"multi_text": "0",

"name": "user_criteria",

"plural": "User Criteria Records",

"primary": "0",

"read_only": "0",

"read_roles": "",

"reference": "",

"reference_cascade_rule": "",

"reference_floats": "0",

"reference_key": "",

"reference_qual": "",

"reference_qual_condition": "",

"reference_type": "",

"sizeclass": "26",

"sortable": "1",

"spell_check": "0",

"staged": "0",

"sys_package": "1ecfe9da8db0021087de63ac7f1f00ab",

"sys_scope": "global",

"table_reference": "0",

"text_index": "0",

"type": "0",

"type_description": "collection",

"unique": "0",

"url": "",

"url_target": "",

"use_dynamic_default": "0",

"use_reference_qualifier": "simple",

"virtual": "0",

"widget": "",

"write_roles": "",

"xml_view": "0"

},

"short_description": {},

"role": {},

"advanced": {},

"sys_updated_on": {},

"sys_class_name": {},

"sys_id": {},

"sys_updated_by": {},

"sys_created_on": {},

"sys_domain": {},

"sys_name": {},

"company": {},

"sys_scope": {},

"department": {},

"sys_created_by": {},

"group": {},

"sys_mod_count": {},

"active": {},

"sys_domain_path": {},

"sys_tags": {},

"script": {},

"sys_package": {},

"sys_update_name": {},

"name": {},

"match_all": {},

"location": {},

"user": {},

"sys_policy": {}

}

}
How to fetch the content that is modified from the user_criteria table where ever there is any modifications in it.