# Observations This document specifies the JANI extension `x-observations` extending the *JANI model interchange format* with support for *observations*. When enabled, edges can be annotated with a field `observation` containing a non-empty array inducing a probability distribution over actions for each transition. When taken, any of the actions will be *observed* with the specified probability. ```js { [...], "?observation": Array.of({ "label": Identifier, "?arguments": Array.of(Expression), "?probability": Expression }) } ``` ```{note} Add support for observations when entering or leaving a state. ```