Period-bound engagement aggregates over the activity feed. period is required (half-open [from, to) on occurred_at; occurred_at operators inside filter are ignored, created_at ones apply); group_by category | type | object_type adds per-group counts and metrics. Returns first_occurred_at, last_occurred_at and active_days_count; per-kind counts ride aggregated.counts.groups. Row-level history: search_activities.

Contract:

• MCP tool get_activities_metrics, registry package mcp.playtables/activities, mount playtables.people.
• Operation metrics, response envelope metrics.
• Flags: read only.