I've seen a number of SDKs in the IBM Cloud for Speech to Text but not a document with the JSON Schema for something like OpenAPI 2.0 (Swagger). We need to use that in our case. Does that exist?
As per the warning mentioned in the link
"IBM provides these older versions of the Watson APIs in Swagger version 2.0 format (the "Swagger APIs"). You may use the Swagger APIs to provide capabilities or integrations that leverage the older versions of the APIs. The Swagger APIs are provided as-is, and IBM does not make any commitments about the quality, reliability, availability, or ability of the Swagger APIs to meet your needs.
In short, The OpenAPI 2.0 specifications are deprecated and are not maintained.
You can use the API docs as documented here
If you still want Swagger(OpenAPI 2.0) schema, here are the steps
Disclaimer: Not recommended. For viewing the schema only