diff --git a/tools/CMakeLists.txt b/tools/CMakeLists.txt
index b79914b20..4ea9241f7 100644
--- a/tools/CMakeLists.txt
+++ b/tools/CMakeLists.txt
@@ -1,14 +1,32 @@
 set(EXECUTABLE_OUTPUT_PATH ${PROJECT_BINARY_DIR}/bin)
 
-set(rime_api_console_src "rime_api_console.cc")
-add_executable(rime_api_console ${rime_api_console_src})
-target_link_libraries(rime_api_console
+set(rime_console_deps
   ${rime_library}
   ${rime_dict_library}
   ${rime_gears_library}
   ${rime_levers_library}
   ${rime_plugins_library})
 
+set(rime_api_console_src "rime_api_console.cc")
+add_executable(rime_api_console ${rime_api_console_src})
+target_link_libraries(rime_api_console ${rime_console_deps})
+
+set(CAPNPC_IMPORT_DIRS ${CAPNPC_IMPORT_DIRS} ${RIME_PROTO_SCHEMA_DIR})
+capnp_generate_cpp(CAPNP_SRCS CAPNP_HDRS rime_message.capnp)
+message(STATUS "compiled capnproto schemata (sources): ${CAPNP_SRCS}")
+message(STATUS "compiled capnproto schemata (headers): ${CAPNP_HDRS}")
+
+set(rime_proto_console_src
+  "rime_proto_console.cc"
+  ${CAPNP_SRCS}
+  ${rime_proto_objs})
+add_executable(rime_proto_console ${rime_proto_console_src})
+target_link_libraries(rime_proto_console ${rime_console_deps})
+target_include_directories(rime_proto_console
+  PRIVATE
+  ${CMAKE_CURRENT_BINARY_DIR}
+  ${RIME_PROTO_INCLUDE_DIR})
+
 set(rime_patch_src "rime_patch.cc")
 add_executable(rime_patch ${rime_patch_src})
 target_link_libraries(rime_patch
@@ -20,12 +38,7 @@ if(NOT (WIN32 AND BUILD_SHARED_LIBS))
 
 set(rime_console_src "rime_console.cc")
 add_executable(rime_console ${rime_console_src})
-target_link_libraries(rime_console
-  ${rime_library}
-  ${rime_dict_library}
-  ${rime_gears_library}
-  ${rime_levers_library}
-  ${rime_plugins_library})
+target_link_libraries(rime_console ${rime_console_deps})
 
 set(rime_dict_manager_src "rime_dict_manager.cc")
 add_executable(rime_dict_manager ${rime_dict_manager_src})
diff --git a/tools/rime_message.capnp b/tools/rime_message.capnp
new file mode 100644
index 000000000..440755bcc
--- /dev/null
+++ b/tools/rime_message.capnp
@@ -0,0 +1,9 @@
+@0xd30600b3651feef7;
+
+using Rime = import "/rime_proto.capnp";
+
+struct RimeMessage {
+  commit @0 :Rime.Commit;
+  context @1 :Rime.Context;
+  status @2 :Rime.Status;
+}
diff --git a/tools/rime_proto_console.cc b/tools/rime_proto_console.cc
new file mode 100644
index 000000000..55fe770af
--- /dev/null
+++ b/tools/rime_proto_console.cc
@@ -0,0 +1,224 @@
+/*
+ * Copyright RIME Developers
+ * Distributed under the BSD License
+ *
+ * 2011-08-29 GONG Chen <chen.sst@gmail.com>
+ */
+#include <algorithm>
+#include <iostream>
+#include <string>
+#include <capnp/message.h>
+#include <rime_api.h>
+#include <rime_message.capnp.h>
+#include <rime_proto.capnp.h>
+
+void print_status(rime::proto::Status::Reader status) {
+  std::cout << "schema: " << status.getSchemaId().cStr()
+            << " / " << status.getSchemaName().cStr() << std::endl;
+  std::cout << "status:";
+  if (status.getIsDisabled()) std::cout << " disabled";
+  if (status.getIsComposing()) std::cout << " composing";
+  if (status.getIsAsciiMode()) std::cout << " ascii";
+  if (status.getIsFullShape()) std::cout << " full_shape";
+  if (status.getIsSimplified()) std::cout << " simplified";
+  std::cout << std::endl;
+}
+
+void print_composition(rime::proto::Context::Composition::Reader composition) {
+  if (!composition.hasPreedit()) return;
+  std::string preedit = composition.getPreedit();
+  size_t len = composition.getLength();
+  size_t start = composition.getSelStart();
+  size_t end = composition.getSelEnd();
+  size_t cursor = composition.getCursorPos();
+  for (size_t i = 0; i <= len; ++i) {
+    if (start < end) {
+      if (i == start) {
+        std::cout << '[';
+      } else if (i == end) {
+        std::cout << ']';
+      }
+    }
+    if (i == cursor) std::cout << '|';
+    if (i < len)
+      std::cout << preedit[i];
+  }
+  std::cout << std::endl;
+}
+
+void print_menu(rime::proto::Context::Menu::Reader menu) {
+  int num_candidates = menu.getCandidates().size();
+  if (num_candidates == 0) return;
+  std::cout << "page: " << (menu.getPageNumber() + 1)
+            << (menu.getIsLastPage() ? '$' : ' ')
+            << " (of size " << menu.getPageSize() << ")" << std::endl;
+  for (int i = 0; i < num_candidates; ++i) {
+    bool highlighted = i == menu.getHighlightedCandidateIndex();
+    auto candidate = menu.getCandidates()[i];
+    std::cout << (i + 1) << ". "
+              << (highlighted ? '[' : ' ')
+              << candidate.getText().cStr()
+              << (highlighted ? ']' : ' ');
+    if (candidate.hasComment())
+      std::cout << candidate.getComment().cStr();
+    std::cout << std::endl;
+  }
+}
+
+void print_context(rime::proto::Context::Reader context) {
+  auto composition = context.getComposition();
+  if (composition.getLength() > 0) {
+    print_composition(composition);
+    print_menu(context.getMenu());
+  } else {
+    std::cout << "(not composing)" << std::endl;
+  }
+}
+
+void print(RimeSessionId session_id) {
+  RimeApi* rime = rime_get_api();
+
+  ::capnp::MallocMessageBuilder message_builder;
+  RimeMessage::Builder root = message_builder.initRoot<RimeMessage>();
+
+  auto commit_builder = root.getCommit();
+  rime->commit_proto(session_id, &commit_builder);
+  auto commit_reader = commit_builder.asReader();
+  if (commit_reader.hasText()) {
+    std::cout << "commit: " << commit_reader.getText().cStr() << std::endl;
+  }
+
+  auto status_builder = root.getStatus();
+  rime->status_proto(session_id, &status_builder);
+  print_status(status_builder.asReader());
+
+  auto context_builder = root.getContext();
+  rime->context_proto(session_id, &context_builder);
+  print_context(context_builder.asReader());
+}
+
+inline static bool is_prefix_of(const std::string& str,
+                                const std::string& prefix) {
+  return std::mismatch(prefix.begin(),
+                       prefix.end(),
+                       str.begin()).first == prefix.end();
+}
+
+bool execute_special_command(const std::string& line,
+                             RimeSessionId session_id) {
+  RimeApi* rime = rime_get_api();
+  if (line == "print schema list") {
+    RimeSchemaList list;
+    if (rime->get_schema_list(&list)) {
+      std::cout << "schema list:" << std::endl;
+      for (size_t i = 0; i < list.size; ++i) {
+        std::cout << (i + 1) << ". " << list.list[i].name
+                  << " [" << list.list[i].schema_id << "]" << std::endl;
+      }
+      rime->free_schema_list(&list);
+    }
+    char current[100] = {0};
+    if (rime->get_current_schema(session_id, current, sizeof(current))) {
+      std::cout << "current schema: [" << current << "]" << std::endl;
+    }
+    return true;
+  }
+  const std::string kSelectSchema = "select schema ";
+  if (is_prefix_of(line, kSelectSchema)) {
+    auto schema_id = line.substr(kSelectSchema.length());
+    if (rime->select_schema(session_id, schema_id.c_str())) {
+      std::cout << "selected schema: [" << schema_id << "]" << std::endl;
+    }
+    return true;
+  }
+  const std::string kSelectCandidate = "select candidate ";
+  if (is_prefix_of(line, kSelectCandidate)) {
+    int index = std::stoi(line.substr(kSelectCandidate.length()));
+    if (index > 0 &&
+        rime->select_candidate_on_current_page(session_id, index - 1)) {
+      print(session_id);
+    } else {
+      std::cerr << "cannot select candidate at index " << index << "."
+                << std::endl;
+    }
+    return true;
+  }
+  if (line == "print candidate list") {
+    RimeCandidateListIterator iterator = {0};
+    if (rime->candidate_list_begin(session_id, &iterator)) {
+      while (rime->candidate_list_next(&iterator)) {
+        std::cout << (iterator.index + 1) << ". " << iterator.candidate.text;
+        if (iterator.candidate.comment)
+          std::cout << " (" << iterator.candidate.comment << ")";
+        std::cout << std::endl;
+      }
+      rime->candidate_list_end(&iterator);
+    } else {
+      std::cout << "no candidates." << std::endl;
+    }
+    return true;
+  }
+  const std::string kSetOption = "set option ";
+  if (is_prefix_of(line, kSetOption)) {
+    Bool is_on = True;
+    auto iter = line.begin() + kSetOption.length();
+    const auto end = line.end();
+    if (iter != end && *iter == '!') {
+      is_on = False;
+      ++iter;
+    }
+    auto option = std::string(iter, end);
+    rime->set_option(session_id, option.c_str(), is_on);
+    std::cout << option << " set " << (is_on ? "on" : "off") << std::endl;
+    return true;
+  }
+  return false;
+}
+
+void on_message(void* context_object,
+                RimeSessionId session_id,
+                const char* message_type,
+                const char* message_value) {
+  std::cout << "message: [" << session_id << "] [" << message_type << "] "
+            << message_value << std::endl;
+}
+
+int main(int argc, char *argv[]) {
+  RimeApi* rime = rime_get_api();
+
+  RIME_STRUCT(RimeTraits, traits);
+  traits.app_name = "rime.console";
+  rime->setup(&traits);
+
+  rime->set_notification_handler(&on_message, NULL);
+
+  std::cerr << "initializing..." << std::endl;
+  rime->initialize(NULL);
+  Bool full_check = True;
+  if (rime->start_maintenance(full_check))
+    rime->join_maintenance_thread();
+  std::cerr << "ready." << std::endl;
+
+  RimeSessionId session_id = rime->create_session();
+  if (!session_id) {
+    std::cerr << "Error creating rime session." << std::endl;
+    return 1;
+  }
+
+  std::string line;
+  while (std::getline(std::cin, line)) {
+    if (line == "exit")
+      break;
+    if (execute_special_command(line, session_id))
+      continue;
+    if (rime->simulate_key_sequence(session_id, line.c_str())) {
+      print(session_id);
+    } else {
+      std::cerr << "Error processing key sequence: " << line << std::endl;
+    }
+  }
+
+  rime->destroy_session(session_id);
+  rime->finalize();
+  return 0;
+}