The following events can be registered through CallbackHandler-1.0:

fired after a new artifact has been added

1. artifactID (number) - itemID of the added artifact

fired after the active artifact was replaced

1. newActiveID (number or nil) - itemID of the currently active artifact
2. oldActiveID (number or nil) - itemID of the previously active artifact

1. type (string) - the type of missing data. Currently either "artifact", meaning some artifact(s) was/were not scanned at all, or "knowledge", meaning the stored knowledgeMultiplier does not correspond to the knowledgeLevel.
2. numArtifactsMissing or knowledgeLevel (number) - The return depends on the type. For type "artifact" - how many artifacts are not yet found (open your bank!). For type "knowledge" - the new knowledge level. The multiplier can be only acquired if an artifact is viewed or the addon keeps a table of level-multiplier pairs (those relationships are likely to change through the course of the expansion though as this is intended as a catch-up mechanic).

Fired after a new weapon has been equipped

1. newArtifactID (number or nil) - itemID of the newly equipped artifact or nil if it is not an artifact
2. oldArtifactID (number or nil) - itemID of the previously equipped artifact or nil if either no artifact was equipped or LAD just got the data

1. knowledgeLevel (number)
2. knowledgeMultiplier (number)

fired after the player gained or spent artifact power

1. artifactID (number)
2. unspentPower (number)
3. power (number)
4. maxPower (number)
5. powerForNextRank (number)
6. numRanksPurchased (number)
7. numRanksPurchasable (number)

fired after the item in a relic slot changed or the slot has been unlocked

1. artifactID (number) - itemID of the artifact that the event was fired for
2. slotIndex (number) - index of the changed relic slot (between 1 and 3)
3. relicData (table) - as in artifacts[artifactID].relics[slotIndex] (see Data structure)

fired either after an artifact respec, or a relic has changed or the player has purchased new traits

1. artifactID (number) - itemID of the artifact that the event was fired for
2. traitsData (table) - as in artifacts[artifactID].traits (see Data structure)