This page will document EventLogging's EventCapsule, a wrapper that stores meta information about EventLogging events. The EventCapsule is stored in the EventLogging source code in eventlogging/capsule.py. Before February 2018, it was stored with other schemas on meta wiki. As part of https://phabricator.wikimedia.org/T179836, it was moved to source code, as the codebase's operation is highly dependent on the EventCapsule structure. Changes to EventCapsule need to be coordinated with source code deployments.
https://meta.wikimedia.org/wiki/Schema:EventCapsule will be maintained for documentation purposes, but the canonical EventCapsule schema lives at https://github.com/wikimedia/eventlogging/blob/master/eventlogging/capsule.py eventlogging/capsule.py.