Websocket Real Time Optimized: Fields schema

Hello,

We are developing a client for the Real Time Optimized API over websockets and we are struggling to find the schema of the Fields in the json message. We are interested in the ELEKTRON_DD service.

This message starts as:

[
  {
    "Fields":{
      "30D_ATM_IV":null,
      "30D_A_IV_C":null,
      "30D_A_IV_P":null,
      "60D_ATM_IV":null,
      "60D_A_IV_C":null,
      "60D_A_IV_P":null,
      "90D_ATM_IV":null,
      "90D_A_IV_C":null,
      "90D_A_IV_P":null,
      "ACTIV_DATE":"2022-08-24",

The protocol specification (see here https://github.com/Refinitiv/websocket-api/blob/master/WebsocketAPI_ProtocolSpecification.pdf) talks about the Fields (page 51) but gives no information about schema.

There seem to be several questions around this in here, but none of them point to a workable answer. For example, an answer to this question points to a dead link https://community.developers.refinitiv.com/questions/14153/where-can-i-find-the-list-of-fields-available-for.html

while the links in the answer to this question all lead to the Reuters developer portal

https://community.developers.refinitiv.com/questions/34010/urgent-feild-descriptions-of-websocket-api-data.html

So could you please point to a specific page or document where we can see the schema used for these Fields?