diff --git a/CMakeLists.txt b/CMakeLists.txt
index c9578ad1ad2f4..f8491759730f1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -406,6 +406,16 @@ if(gRPC_BUILD_GRPCPP_OTEL_PLUGIN)
   include(cmake/opentelemetry-cpp.cmake)
 endif()
 
+# Setup external proto library at third_party/cel-spec if it doesn't exist
+if (NOT EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/third_party/cel-spec AND gRPC_DOWNLOAD_ARCHIVES)
+  # Download the archive via HTTP, validate the checksum, and extract to third_party/cel-spec.
+  download_archive(
+    ${CMAKE_CURRENT_SOURCE_DIR}/third_party/cel-spec
+    https://github.com/google/cel-spec/archive/v0.19.1.tar.gz
+    0661174bb0c965c72f2d037d9d8e8717ed20f9a64f9b1be9851069f9277c9508
+    cel-spec-0.19.1
+  )
+endif()
 # Setup external proto library at third_party/envoy-api with 2 download URLs
 if (NOT EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/third_party/envoy-api AND gRPC_DOWNLOAD_ARCHIVES)
   # Download the archive via HTTP, validate the checksum, and extract to third_party/envoy-api.
@@ -803,6 +813,12 @@ protobuf_generate_grpc_cpp_with_import_path_correction(
 protobuf_generate_grpc_cpp_with_import_path_correction(
   test/core/tsi/alts/fake_handshaker/transport_security_common.proto test/core/tsi/alts/fake_handshaker/transport_security_common.proto
 )
+protobuf_generate_grpc_cpp_with_import_path_correction(
+  third_party/cel-spec/proto/cel/expr/checked.proto proto/cel/expr/checked.proto
+)
+protobuf_generate_grpc_cpp_with_import_path_correction(
+  third_party/cel-spec/proto/cel/expr/syntax.proto proto/cel/expr/syntax.proto
+)
 protobuf_generate_grpc_cpp_with_import_path_correction(
   third_party/envoy-api/envoy/admin/v3/certs.proto envoy/admin/v3/certs.proto
 )
@@ -6894,6 +6910,14 @@ endif()
 if(gRPC_BUILD_TESTS)
 
 add_executable(admin_services_end2end_test
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.h
@@ -26989,6 +27013,14 @@ add_executable(pre_stop_hook_server_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.h
@@ -36967,6 +36999,14 @@ add_executable(xds_audit_logger_registry_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -37446,6 +37486,14 @@ add_executable(xds_client_test
   ${_gRPC_PROTO_GENS_DIR}/test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.pb.h
   ${_gRPC_PROTO_GENS_DIR}/test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.h
@@ -38041,6 +38089,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -38556,6 +38612,14 @@ endif()
 if(gRPC_BUILD_TESTS)
 
 add_executable(xds_cluster_resource_type_test
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -39088,6 +39152,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -39610,6 +39682,14 @@ add_executable(xds_common_types_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -40053,6 +40133,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -40698,6 +40786,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.h
@@ -41321,6 +41417,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -42170,6 +42274,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -42700,6 +42812,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -43238,6 +43358,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -43772,6 +43900,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -44294,6 +44430,14 @@ add_executable(xds_http_filters_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -44768,6 +44912,14 @@ add_executable(xds_lb_policy_registry_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -45154,6 +45306,14 @@ add_executable(xds_listener_resource_type_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -45652,6 +45812,14 @@ endif()
 if(gRPC_BUILD_TESTS)
 
 add_executable(xds_matcher_parse_test
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -46427,6 +46595,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -46965,6 +47141,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -47594,6 +47778,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -48133,6 +48325,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -48676,6 +48876,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -49198,6 +49406,14 @@ add_executable(xds_route_config_resource_type_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/reflection/v1alpha/reflection.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -49609,6 +49825,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -50147,6 +50371,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -50703,6 +50935,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
@@ -51254,6 +51494,14 @@ add_executable(xds_stats_watcher_test
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.pb.h
   ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/test.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+  ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.grpc.pb.cc
   ${_gRPC_PROTO_GENS_DIR}/envoy/admin/v3/certs.pb.h
@@ -51837,6 +52085,14 @@ if(_gRPC_PLATFORM_LINUX OR _gRPC_PLATFORM_MAC OR _gRPC_PLATFORM_POSIX)
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.pb.h
     ${_gRPC_PROTO_GENS_DIR}/src/proto/grpc/testing/simple_messages.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/checked.grpc.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.cc
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.pb.h
+    ${_gRPC_PROTO_GENS_DIR}/proto/cel/expr/syntax.grpc.pb.h
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.grpc.pb.cc
     ${_gRPC_PROTO_GENS_DIR}/envoy/annotations/deprecation.pb.h
diff --git a/build_autogenerated.yaml b/build_autogenerated.yaml
index ad9fb0acaa086..bd8182e53369b 100644
--- a/build_autogenerated.yaml
+++ b/build_autogenerated.yaml
@@ -5698,6 +5698,8 @@ targets:
   - src/cpp/server/csds/csds.h
   - third_party/protoc-gen-validate/validate/validate.h
   src:
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/admin/v3/certs.proto
   - third_party/envoy-api/envoy/admin/v3/clusters.proto
   - third_party/envoy-api/envoy/admin/v3/config_dump.proto
@@ -19912,6 +19914,8 @@ targets:
   - src/proto/grpc/testing/istio_echo.proto
   - src/proto/grpc/testing/messages.proto
   - src/proto/grpc/testing/test.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/admin/v3/certs.proto
   - third_party/envoy-api/envoy/admin/v3/clusters.proto
   - third_party/envoy-api/envoy/admin/v3/config_dump.proto
@@ -26886,6 +26890,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/core/v3/address.proto
@@ -27020,6 +27026,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - test/core/event_engine/fuzzing_event_engine/fuzzing_event_engine.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/admin/v3/certs.proto
   - third_party/envoy-api/envoy/admin/v3/clusters.proto
   - third_party/envoy-api/envoy/admin/v3/config_dump.proto
@@ -27189,6 +27197,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -27328,6 +27338,8 @@ targets:
   - test/core/test_util/scoped_env_var.h
   - third_party/protoc-gen-validate/validate/validate.h
   src:
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -27478,6 +27490,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -27775,6 +27789,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/core/v3/address.proto
@@ -27958,6 +27974,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -28135,6 +28153,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/admin/v3/certs.proto
   - third_party/envoy-api/envoy/admin/v3/clusters.proto
   - third_party/envoy-api/envoy/admin/v3/config_dump.proto
@@ -28307,6 +28327,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -28543,6 +28565,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -28690,6 +28714,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -28838,6 +28864,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -28987,6 +29015,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -29133,6 +29163,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -29265,6 +29297,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/cluster/v3/circuit_breaker.proto
@@ -29374,6 +29408,8 @@ targets:
   - third_party/protoc-gen-validate/validate/validate.h
   src:
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -29581,6 +29617,8 @@ targets:
   - src/core/ext/upb-gen/xds/type/v3/typed_struct.upb_minitable.h
   - third_party/protoc-gen-validate/validate/validate.h
   src:
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/common/matcher/v3/matcher.proto
@@ -29815,6 +29853,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -29964,6 +30004,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -30143,6 +30185,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -30295,6 +30339,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -30447,6 +30493,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -30593,6 +30641,8 @@ targets:
   src:
   - src/proto/grpc/lookup/v1/rls_config.proto
   - src/proto/grpc/reflection/v1alpha/reflection.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/core/v3/address.proto
@@ -30710,6 +30760,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -30861,6 +30913,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -31017,6 +31071,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -31167,6 +31223,8 @@ targets:
   - src/proto/grpc/testing/empty.proto
   - src/proto/grpc/testing/messages.proto
   - src/proto/grpc/testing/test.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/admin/v3/certs.proto
   - third_party/envoy-api/envoy/admin/v3/clusters.proto
   - third_party/envoy-api/envoy/admin/v3/config_dump.proto
@@ -31326,6 +31384,8 @@ targets:
   - src/proto/grpc/testing/echo.proto
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/simple_messages.proto
+  - third_party/cel-spec/proto/cel/expr/checked.proto
+  - third_party/cel-spec/proto/cel/expr/syntax.proto
   - third_party/envoy-api/envoy/annotations/deprecation.proto
   - third_party/envoy-api/envoy/annotations/resource.proto
   - third_party/envoy-api/envoy/config/accesslog/v3/accesslog.proto
@@ -31477,6 +31537,12 @@ targets:
   - posix
   - mac
 external_proto_libraries:
+- destination: third_party/cel-spec
+  hash: 0661174bb0c965c72f2d037d9d8e8717ed20f9a64f9b1be9851069f9277c9508
+  proto_prefix: third_party/cel-spec/
+  strip_prefix: cel-spec-0.19.1
+  urls:
+  - https://github.com/google/cel-spec/archive/v0.19.1.tar.gz
 - destination: third_party/envoy-api
   hash: cd8b49614408b43bd45d90e3e98d69e24eea632ff42ac3bfb8bca68bc31e377f
   proto_prefix: third_party/envoy-api/