How to update index.json

I have a new device and GS.GS_MCU_ZB20x.1.0.0.pack &&GS.GS_MCU_ZB20x.pdsc ,and i create a custom_targets.json to support my device . this project can run in mbed studio .I want to export to keil5 but tool report’ZB200 not supported by uvision5’.I think i should generate “index.json”. but i don’t konw how to update"index.json" with ‘GS.GS_MCU_ZB20x.1.0.0.pack’&& arm_pack_manager .I can’t find doc
json is
“ZB20X”: {
“inherits”: [“Target”],
“core”: “Cortex-M3”,
“supported_toolchains”: [
“device_has”: [“MPU”],
“extra_labels_add”: [
“detect_code”: [
“ZB200”: {
“inherits”: [“ZB20X”],
“macros_add”: [“CHILD_MACRO1”],
“device_name”: “ZB200”,
“extra_labels_add”: [