{
  "_comment": "params.message has neither content nor parts. Pre-PR-2349 the SDK silently rejected this post-handler-dispatch and the rejection was invisible to the sender. Now normalizeA2APayload returns a loud HTTP 400.",
  "_added": "2026-04-30",
  "_source": "PR #2349 incident edge case",
  "_expect_error": "params.message must contain either 'parts' (v0.3) or 'content' (v0.2 compat)",
  "_expect_status": 400,
  "jsonrpc": "2.0",
  "method": "message/send",
  "id": "msg-test-invalid-empty",
  "params": {
    "message": {
      "messageId": "msg-bad-1",
      "role": "user"
    }
  }
}
