usage/changed

The host’s last-observed subscription usage DATA changed (window, weekly, or tier — not a stamp-only refresh), with the same payload shape as usage/read’s usage member; the absent-to-present first observation emits (ADR 32563 D3).

Parameters

Type: SubscriptionUsage

The one usage payload shape: the usage/read result’s usage member and the usage/changed params (ADR 32563 D2/D3). The numbers are point-in-time — observedAtMs is the host’s arrival stamp, so a client renders “as of”, never implies live data.

Field	Type	Stability	Presence	Description
observedAtMs	integer		required	When the host RECEIVED this observation (frame arrival or mint request-send), epoch milliseconds.
tier	string		required	The provider’s subscription tier id, verbatim.
weekly	SubscriptionUsageWeekly		required	The rolling weekly block.
window	SubscriptionUsageWindow		required	The current window.

Source

schema/msp/experimental/msp.schema.json#/notifications/usage~2Fchanged

{
  "description": "The host's last-observed subscription usage DATA changed (window, weekly, or tier — not a stamp-only refresh), with the same payload shape as usage/read's usage member; the absent-to-present first observation emits (ADR 32563 D3).",
  "params": {
    "$ref": "#/$defs/SubscriptionUsage"
  }
}