{
  "instruction": "Enforce message ordering and deduplication for real-time messages",
  "relevant_when": "Agent implements real-time features where message order matters (chat, status updates, collaborative editing) or where reconnection can cause duplicate message delivery",
  "context": "Network issues and reconnection can cause messages to arrive out of order or be delivered twice. Without sequence numbers or timestamps, a stale update can overwrite a newer one. Without deduplication, the same message may be processed multiple times.",
  "sources": [
    {
      "type": "file",
      "filename": "skills/realtime-web-patterns/SKILL.md",
      "tile": "tessl-labs/realtime-web-patterns@0.2.0"
    }
  ],
  "checklist": [
    {
      "name": "sequence-or-timestamp-ordering",
      "rule": "Messages include a sequence number or timestamp, and the client rejects or reorders messages that arrive out of sequence rather than blindly applying every update",
      "relevant_when": "Agent implements real-time updates where ordering matters"
    },
    {
      "name": "deduplication-after-reconnect",
      "rule": "Client deduplicates messages using message IDs or sequence numbers to prevent processing the same message twice after reconnection",
      "relevant_when": "Agent implements real-time features with reconnection where duplicate delivery is possible"
    }
  ]
}