This environment variable specifies the client secret of the Microsoft Identity Platform app registration used to authenticate Azure Event Hub ingest feeds. It is required for self-hosted deployments and must be set alongside AZURE_INGEST_FEED_TENANT_ID and AZURE_INGEST_FEED_DEFAULT_CLIENT_ID.

To obtain the secret value, generate a secret in the app registration on the Microsoft Identity Platform. Save the value immediately — it is only shown once.