Adding Custom values in Identity Server 4 Connect/token endpoint

i have implemented the Identity server 4 .. one thing on which i am stuck is currently connect/token endpoint provides the following fields

{
  "id_token": "id toekn value",
  "access_token": "access token value",
  "token_type": "Bearer",
  "refresh_token": "a refresh token",
  "scope": "some scopes"
}

however i want to add some more fields in this like

{
  "id_token": "id toekn value",
  "access_token": "access token value",
  "token_type": "Bearer",
  "refresh_token": "a refresh token",
  "scope": "some scopes",
  "id":"any id",
  "url":"any url"
}

any way to intercept this call and add custom fileds???