To have transcription in Salesforce Service Cloud Voice, the languageCode must be set, “Start media streaming” element should be invoked and finally the “kvsConsumerTrigger” lambda function should be invoked. The kvsConsumerTrigger Lambda function invokes the kvsTranscriber Lambda Function.

Reference Article:

https://developer.salesforce.com/docs/atlas.en-us.voice_developer_guide.meta/voice_developer_guide/voice_lambda_kvsconsumertrigger.htm

Sample Contact flow(inbound) for transcription:

1. Use “Set contact attributes” element to set languageCode. 

2. Use “Start media streaming” element. 

3. Use “Invoke AWS Lambda function” element. Invoke “kvsConsumerTrigger” lambda function.

Output: