curl --request GET \
  --url https://api.octav.fi/v1/beacon/validators/details/index/{index} \
  --header 'Authorization: Bearer <token>'

{
  "validator": {
    "index": 123,
    "pubkey": "<string>",
    "slashed": true
  },
  "lifecycle": {
    "activationEpoch": 123,
    "activationTimestamp": 123,
    "exitEpoch": 123,
    "withdrawableEpoch": 123
  },
  "balance": {
    "actual": "<string>",
    "effective": "<string>"
  },
  "withdrawalCredentials": {
    "prefix": 123,
    "credential": "<string>",
    "address": "<string>"
  }
}