# RevisionCauseFace

object type

WHY one revision exists: the machine cause, with the caller's reason VERBATIM when the operation carried one, and — since locked — WHO as the typed actor face.

## Fields

| Field | Type | Notes |
| --- | --- | --- |
| `kind` | [String](/types/#scalars) `String!` | create (birth) · edit (an attribute revision) · transition (an FSM state change). |
| `event` | [String](/types/#scalars) | The success-form event name of the matched transition (transitions only). |
| `op` | [String](/types/#scalars) | The transition trigger token (e.g. doom, activate); absent on creates/edits. |
| `reason` | [String](/types/#scalars) | The caller-supplied reason, VERBATIM; never required, never blank. |
| `actor` | [RevisionActorFace](/types/RevisionActorFace/) | WHO wrote this revision; null on pre-provenance revisions. |