Seems like all response from the Gerrit API starts with a line with the content:
)]}'
For example, https://gerrit.wikimedia.org/r/changes/I56f5c03fea40af3ee4ec50f258516d0833625c6e returns:
)]}'
{
"id": "labs%2Ftools%2FIsa~master~I56f5c03fea40af3ee4ec50f258516d0833625c6e",
"project": "labs/tools/Isa",
"branch": "master",
"topic": "daily-contrib-graph",
"hashtags": [],
...Another example, https://gerrit.wikimedia.org/r/accounts/689 returns:
)]}'
{
"_account_id": 689,
"name": "Gabrielchihonglee",
"email": "chihonglee777@gmail.com",
"username": "gabrielchihonglee"
}