Currently, the Webhook notification channel type in Harness does not support configuring a custom request body. The webhook sends a notification without a payload body, which makes it impossible to integrate with external systems that require a body in the HTTP request.

Use case:

We use webhooks to trigger automated AWS agent investigations whenever a pipeline step fails (e.g. GitOps sync failures, timeout errors). The AWS endpoint receiving the webhook requires a JSON body to identify the pipeline, stage, execution context, and failure reason. Without body support, the webhook call is rejected and the automation cannot be triggered.

Requested behavior:

Allow users to define a custom body for webhook notifications, with support for Harness expression variables (e.g. <+pipeline.executionId>, <+pipeline.name>, <+stage.name>, <+failure.message>) so the payload can carry execution context dynamically.