Attachments: Up to 2 attachments (including images) can be used with a maximum of 512.0 KiB each and 1.0 MiB total.
The data in the websockets API is JSON messages. The protocol tr_json2 is described in the documents here.
Websocket API encoding protocols
How to connect web socket API using python?
Implementation of ERT : questions about token
make sure that api.refinitiv.com is used for Service Discovery
How does the application handle RMTES strings? (from WebSocket API Webinar Nov 29)