{ "$schema": "https://json-schema.org/draft/2020-12/schema", "$id": "#/components/schemas/PlannerExternalReference", "title": "PlannerExternalReference", "type": "object", "description": "An external reference attached to a Planner task", "properties": { "@odata.type": { "type": "string", "const": "microsoft.graph.plannerExternalReference", "example": "example_value" }, "alias": { "type": "string", "description": "A name alias for the reference", "example": "example_value" }, "lastModifiedBy": { "$ref": "#/components/schemas/IdentitySet", "readOnly": true }, "lastModifiedDateTime": { "type": "string", "format": "date-time", "description": "The date and time the reference was last modified", "readOnly": true, "example": "2026-01-15T10:30:00Z" }, "previewPriority": { "type": "string", "description": "Hint used to set the relative priority order in which the reference will be shown as a preview on the task", "example": "example_value" }, "type": { "type": "string", "description": "The type of the reference (e.g., PowerPoint, Word, Excel, Other)", "example": "example_value" } } }