openrtb.field.required
What it means
A field the OpenRTB specification marks as required is absent at this path for the version you validated against. The classic cases: a request without id or imp, an imp without its own id, or a bid without impid or price.
Why it matters
Required fields are the minimum contract of the auction. A request that omits one is invalid per the spec, and strict bidders no-bid it without telling you. Because lenient partners still answer, the traffic looks healthy while the strictest (often highest-paying) demand silently disappears.
How to fix it
Populate the field at the reported JSON path. If your builder assembles objects conditionally, make required fields unconditional and fail the build when a value is unavailable, rather than shipping a partial object.
Example that trips it
{ "imp": [{ "id": "1", "banner": { "w": 300, "h": 250 } }] }Missing the top-level request id.
Check your payload
Paste a bid request or response into the tester to see whether this code fires against it, or gate on the id in CI with the CLI: the id is stable, wording is not.
Back to the full diagnostic code reference.