HTTP status codes

200 OK

The request has been accepted and processed. The response contains a JSON object.

404 Not Found

The server can not find the requested resource, the URL is wrong.

500 Internal Server Error

The server has encountered a situation it doesn't know how to handle.
It can happen when the JSON object posted with the request is invalid.

For example, the following is not a valid JSON object because both the external curly braces and the quotation marks around the properties names are missing.

document: {
    text: "Michael Jordan was one of the best basketball players of all time. Scoring was Jordan's stand-out skill, but he still holds a defensive NBA record, with eight steals in a half."
}