SpellCooldownInfo

startTime

number (If cooldown is active, time started; 0 if no cooldown; Current time if isEnabled is false)

duration

number (Cooldown duration in seconds if active; 0 if cooldown is inactive)

isEnabled

bool, never secret (False if cooldown is on hold (ex: some cooldowns only start after an active spell is cancelled); True otherwise)

isActive

bool, never secret (False if cooldown is not active (ex: not enabled, or startTime or duration are 0); True otherwise)

modRate

number (Rate at which cooldown UI should update)

activeCategory

number, optional (Indicates which category is responsible for determining the duration. A nil value indicates the duration was determined through some other logic, e.g. the spell is on hold.)

timeUntilEndOfStartRecovery

number, optional (When this is set it indicates that the spell is in recovery and this is how long it will be until that recovery period is finished)

isOnGCD

bool, optional, never secret (Whether or not this spell is considered to be on the global cooldown, do not trust this field unless responding to a SPELL_UPDATE_COOLDOWN event)

Present since at least 1.60.1.70707, the first build we track.