1.Create new User and add to Guest group.

Example: User_for_API

2.Test

curl -s -i -X POST -H ‘Content-Type: application/json-rpc’ -d ‘{ “params”: { “user”: “User_for_API “, “password”: “” }, “jsonrpc”: “2.0”, “method”: “user.login”, “id”: 0 }’ ‘http://127.0.0.1/zabbix/api_jsonrpc.php’