Grader: system-event

Taxonomy

Property	Value
Determinism	static
Cost	free
Reference	reference-free
Temporal scope	trajectory-level
Score kind	code

Config

graders:
  - type: system-event
    config:
      required:
        - compaction

Field	Type	Required	Default	Description
required	string[]	No	—	Event types that must occur. Fails if any are missing
disallowed	string[]	No	—	Event types that must not occur. Fails if any are encountered

At least one of required or disallowed must be provided. An event type cannot appear in both lists; vally lint catches this.

Behavior

Scans trajectory events whose type is system and compares their data.eventType values against the configured lists.

Event types

eventType values come from the trajectory source, not a fixed platform enum. See the system event.

• Event types use exact, case-sensitive string comparison.
• A required entry is satisfied when at least one matching event occurs.
• A disallowed entry is violated when any matching event occurs.
• Duplicate occurrences are reported once in result metadata.

The grader passes when every required event occurred and no disallowed event occurred.

Result metadata

Field	Type	Description
required	string[]	Configured required event types, when provided
disallowed	string[]	Configured disallowed event types, when provided
systemEvents	string[]	Sorted, deduplicated event types observed in the trajectory