On the wire
Ships with HTTP status 400, carrying "code": "RU-4020" in the response body alongside the human-readable error message. Existing fields are never replaced by the code: it is additive.
Common causes
- A custom Jira Automation "Send web request" body that does not forward the issue payload unchanged.
- A provider sending a ping/test event with a shape this endpoint does not expect (GitHub's initial "ping" delivery, sent once when a webhook is created, is accepted and ignored rather than treated as this error; a different unrecognized event type is also ignored, not refused -- this code is reserved for a body that genuinely cannot be parsed).
How to fix it
- For Jira, set the Automation "Send web request" body to "Issue data (JSON)" rather than a custom payload.
- Confirm the provider is sending `application/json`, not form-encoded data.
Related codes
Still stuck?
Ask support and mention RU-4020: the code pins down the exact refusal path, so you skip the diagnostic back-and-forth.