diff --git a/docs/services/esi/overview.md b/docs/services/esi/overview.md index bebf9ee0..2b3bd647 100644 --- a/docs/services/esi/overview.md +++ b/docs/services/esi/overview.md @@ -11,8 +11,13 @@ While some ESI endpoints are public, many require authentication, which is handl ## Versioning -Every ESI request can include an `X-Compatibility-Date` header using the ISO format - `YYYY-MM-DD`. This header tells ESI "This application was built or updated at this date - give me the API behavior as it was at that date". If applications cannot set custom headers, the `compatibility_date` query parameter will do the same. -The date cannot be in the future, neither can it below a minimum threshold (the "oldest" versions available). If this minimum bar is raised, this will be clearly communicated via dev-blogs. +Every ESI request can include an `X-Compatibility-Date` header using the ISO format - `YYYY-MM-DD`. +This header tells ESI "This application was built or updated at this date - give me the API behavior as it was at that date". +If applications cannot set custom headers, the `compatibility_date` query parameter will do the same. +If a request does not set a compatibility date, the oldest available compatibility date is used. + +The date cannot be in the future, neither can it below a minimum threshold (the "oldest" versions available). +If this minimum bar is raised, this will be clearly communicated via dev-blogs. The API changes date at 11:00 UTC. So if you want to use the date of today, use (pseudo-code): `now() - 11 * 60 * 60`, to get the current date of the API.