curl --request POST \
  --url https://api.b-bot.space/v2/a2a/{assistant_id} \
  --header 'Accept: <accept>' \
  --header 'Content-Type: application/json' \
  --data '{
  "jsonrpc": "2.0",
  "id": "<string>",
  "method": "message/send",
  "params": {
    "message": {
      "role": "user",
      "parts": [
        {
          "kind": "text",
          "text": "<string>"
        }
      ],
      "messageId": "<string>"
    },
    "thread": {
      "threadId": "<string>"
    }
  }
}'

{
  "jsonrpc": "2.0",
  "id": "<string>",
  "result": {},
  "error": {
    "code": 123,
    "message": "<string>"
  }
}