         date: c.date
           title: 'Date computed'
           description: 'The date a match was computed.'
+        playtime:
+          title: 'Playtime so far'
+          description: 'The total seconds of playtime on this session when the match was computed.'
+          type: 'number'
+        
         metrics:
           type: 'object'
           title: 'Metrics'

                title: 'Opponent User ID'
                description: 'The user ID of an opponent'
                type: ['object','string']
              metrics:
                type: 'object'
                properties:

    type: 'string'
    default: 'javascript'
    
  playtime:
    type: 'number'
    title: 'Playtime'
    default: 0
    description: 'The total playtime on this session'
    
  teamSpells:
    type: 'object'
    additionalProperties:
