An evaluation is a stream of events. Events can be of two types, text and data, and contain a payload.

The payload of text events is a Unicode string. The payload string must be non-empty, and either:

  • does not contain any line-terminator, or
  • consist of a single line-terminator only.

The payload of data events is any JSON value.

Evaluation events as JSON

Each evaluation event is represented as a JSON object, with the following fields.

  • type: a string, with value either data or text, according to the type of the event.
  • payload: the event payload, i.e., either a JSON string (for text events) or any JSON value (for data events).

Evaluation as JSON Lines streams

An evaluation is represented over a stream using the JSON Lines format.