Event taxonomy

Each Refract event describes what changed at a revision boundary. Events are deterministic — the same input always produces the same output. Events chain into claim-state timelines across revisions — see Temporal Model for how events form replayable history.

Claim lifecycle

Event type	Trigger	Example
sentence_first_seen	New sentence text appears	A sentence about a company appears for the first time
sentence_removed	Existing sentence deleted entirely	A controversial paragraph is removed
sentence_modified	Same sentence text changed (similarity threshold match)	Sentence rewording detected by word-overlap ratio
sentence_reintroduced	Previously removed sentence returns	A deleted sentence is restored in a later edit

Citation changes

Event type	Trigger
citation_added	New <ref> tag added
citation_removed	Existing <ref> tag removed
citation_replaced	One citation swapped for another in the same position

Template changes

Event type	Trigger
template_added	New {{template}} added (e.g., {{citation needed}}, {{NPOV}})
template_removed	Template removed
template_parameter_changed	Template parameters modified (e.g., date updated on a maintenance tag)

Section and page structure

Event type	Trigger
section_reorganized	Sections added, removed, or reordered
lead_promotion	Content moves from body into the lead section
lead_demotion	Content moves from lead into the body
page_moved	Page renamed (detected via logevents API)

Links and categories

Event type	Trigger
wikilink_added	New [[internal link]] added
wikilink_removed	Internal link removed
category_added	New [[Category:...]] added
category_removed	Category removed

Content conflict

Event type	Trigger
revert_detected	Edit summary matches one of six default patterns: revert…, undid revision, rvv, rollback, restore…, [[WP:ROLLBACK]]. A bare "rv" or "undo" does not match
edit_cluster_detected	3+ edits within a configurable time window (default: 1 hour). The fact's detail gives revisions, editors (a count of unique editors; no identities recorded), window_ms and single_editor

An edit_cluster_detected event spans the cluster: fromRevisionId is its first revision and toRevisionId its last. --cluster-window sets the window in minutes.

Talk page activity

Event type	Trigger
talk_page_correlated	Article revision has a nearby talk page revision (default: 7 days before, 3 days after)
talk_thread_opened	New discussion thread created on talk page
talk_thread_archived	Thread closed/archived
talk_reply_added	Reply posted in an existing thread
talk_activity_spike	Talk page edits exceed 3x the moving average on a given day

refract analyze and refract export read the ten talk-page edits that precede the last analyzed revision and emit all five events from them. Thread events cover the talk edits made since the first analyzed revision; their revision IDs are talk-page revisions. The CLI looks for spikes among the ten talk-page edits that precede the last analyzed revision, within the seven days before it, so most runs emit none. --spike-factor sets the multiplier. A spike event names a day, not a revision pair: both revision IDs are 0.

Access control

Event type	Trigger
protection_changed	Page protection level changed (protect, unprotect, modify)

Event envelope

All events share a common structure:

interface EvidenceEvent {
  eventType: EventType;       // one of the types above
  fromRevisionId: number;     // parent revision
  toRevisionId: number;       // revision where the change occurred
  section: string;            // section name
  before: string;             // text/state before
  after: string;              // text/state after
  deterministicFacts: DeterministicFact[]; // why this event was produced
  layer: EvidenceLayer;       // observed, policy_coded, model_interpretation, speculative, unknown
  timestamp: string;          // ISO 8601
}