Question regarding ext proc / ExternalProcessor filter in envoy

[newwuhan5]

[2022-09-07 08:18:23.843][2686664][warning][misc] [external/envoy/source/common/protobuf/message_validator_impl.cc:35] message 'envoy.extensions.filters.http.ext_proc.v3.ExternalProcessor' is contained in proto file 'envoy/extensions/filters/http/ext_proc/v3/ext_proc.proto' marked as work-in-progress. API features marked as work-in-progress are not considered stable, are not covered by the threat model, are not supported by the security team, and are subject to breaking changes. Do not use this feature without understanding each of the previous points.

When testing this filter, envoy gives this warning? Any one in the community has used this filter in the PRODUCTION?
- name: envoy.filters.http.ext_proc
typed_config:
"@type": type.googleapis.com/envoy.extensions.filters.http.ext_proc.v3.ExternalProcessor
failure_mode_allow: false
async_mode: false
request_attributes:
- user
response_attributes:
- server
processing_mode:
request_header_mode: "" <= What value to use?
response_header_mode: "" <= What value to use?
request_body_mode: "" <= What value to use?
response_body_mode: "" <= What value to use?
request_trailer_mode: "" <= What value to use?
response_trailer_mode: "" <= What value to use?
grpc_service:
envoy_grpc:
cluster_name: ext_proc_cluster

Any issues or any suggestions? Any ideas are appreciated!