No, it’s not exclusive to API Gateway. dd_resource_key is the CCRID, which represents the underlying cloud resource. For API Gateway inferred spans we want it to be the gateway ARN, and for Lambda spans it should be the Lambda function ARN, so it applies to all inferred spans that represent a cloud resource, not just API Gateway.

Right now, the tag already exists and appears to be set by the backend (since it is already always present and the value we set for API Gateway is being overwrited by the Lambda function ARN instead). The backend team will need to investigate this behavior later, but it shouldn’t block the current work.