chore: import upstream snapshot with attribution

tensorflow/distribute/experimental/rpc/proto/BUILD

@@ -0,0 +1,33 @@
+load("@rules_python//python:proto.bzl", "py_proto_library")
+load(
+    "//tensorflow/core/platform:build_config.bzl",
+    "tf_additional_all_protos",
+    "tf_proto_library",
+)
+
+package(
+    # copybara:uncomment default_applicable_licenses = ["//tensorflow:license"],
+    default_visibility = [
+        "//tensorflow/distribute/experimental/rpc:__subpackages__",
+        "//tensorflow/python/distribute/experimental/rpc:__subpackages__",
+    ],
+    licenses = ["notice"],
+)
+
+tf_proto_library(
+    name = "tf_rpc_service_proto",
+    srcs = ["tf_rpc_service.proto"],
+    has_services = 1,
+    create_go_proto = False,
+    create_grpc_library = True,
+    create_java_proto = False,
+    create_service = True,
+    protodeps = tf_additional_all_protos(),
+)
+
+# copybara:uncomment_begin(google-only)
+# py_proto_library(
+#     name = "tf_rpc_service_py_pb2",
+#     deps = [":tf_rpc_service_proto"],
+# )
+# copybara:uncomment_end

tensorflow/distribute/experimental/rpc/proto/tf_rpc_service.proto

@@ -0,0 +1,50 @@
+// Copyright 2026 The TensorFlow Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ==============================================================================
+
+syntax = "proto3";
+
+package tensorflow.rpc;
+
+import "tensorflow/core/framework/tensor.proto";
+import "tensorflow/core/protobuf/struct.proto";
+
+message CallRequest {
+  string method = 1;
+  repeated TensorProto input_tensors = 2;
+}
+
+message CallResponse {
+  repeated TensorProto output_tensors = 1;
+}
+
+message ListRequest {}
+
+message RegisteredMethod {
+  string method = 1;
+  StructuredValue input_specs = 2;
+  StructuredValue output_specs = 3;
+}
+
+message ListResponse {
+  repeated RegisteredMethod registered_methods = 1;
+}
+
+service RpcService {
+  // RPC for invoking a registered function on remote server.
+  rpc Call(CallRequest) returns (CallResponse) {}
+
+  // RPC for listing available methods in a server.
+  rpc List(ListRequest) returns (ListResponse) {}
+}