wip
diff --git a/test/cpp/interop/client_helper.h b/test/cpp/interop/client_helper.h
index c4361bb..fb8a664 100644
--- a/test/cpp/interop/client_helper.h
+++ b/test/cpp/interop/client_helper.h
@@ -39,6 +39,8 @@
 #include <grpc++/config.h>
 #include <grpc++/channel_interface.h>
 
+#include "test/proto/messages.grpc.pb.h"
+
 namespace grpc {
 namespace testing {
 
@@ -49,6 +51,22 @@
 std::shared_ptr<ChannelInterface> CreateChannelForTestCase(
     const grpc::string& test_case);
 
+grpc::testing::CompressionType
+GetInteropCompressionTypeFromCompressionAlgorithm(
+    grpc_compression_algorithm algorithm);
+
+class InteropClientContextInspector {
+ public:
+  InteropClientContextInspector(const ::grpc::ClientContext& context);
+
+  // Inspector methods, able to peek inside ClientContext, follow.
+  grpc_compression_algorithm GetCallCompressionAlgorithm() const;
+
+ private:
+  const ::grpc::ClientContext& context_;
+};
+
+
 }  // namespace testing
 }  // namespace grpc