curl --request GET \
  --url https://api.tavily.com/usage \
  --header 'Authorization: Bearer <token>'

{
  "key": {
    "usage": 150,
    "limit": 1000
  },
  "account": {
    "current_plan": "Bootstrap",
    "plan_usage": 500,
    "plan_limit": 15000,
    "paygo_usage": 25,
    "paygo_limit": 100
  }
}