diff --git a/td/mtproto/RawConnection.h b/td/mtproto/RawConnection.h
index aeb0503be..5a816cab1 100644
--- a/td/mtproto/RawConnection.h
+++ b/td/mtproto/RawConnection.h
@@ -76,7 +76,7 @@ class RawConnection {
     virtual ~Callback() = default;
     virtual Status on_raw_packet(const PacketInfo &info, BufferSlice packet) = 0;
     virtual Status on_quick_ack(uint64 quick_ack_token) {
-      return Status::Error("quick acks unsupported fully, but still used");
+      return Status::Error("Quick acks unsupported fully, but still used");
     }
     virtual Status before_write() {
       return Status::OK();
diff --git a/td/telegram/ConfigManager.cpp b/td/telegram/ConfigManager.cpp
index 674cf382c..e15cf1c51 100644
--- a/td/telegram/ConfigManager.cpp
+++ b/td/telegram/ConfigManager.cpp
@@ -116,7 +116,7 @@ Result<int32> HttpDate::parse_http_date(std::string slice) {
   auto gmt = p.read_word();
   TRY_STATUS(std::move(p.status()));
   if (gmt != "GMT") {
-    return Status::Error("timezone must be GMT");
+    return Status::Error("Timezone must be GMT");
   }
 
   static Slice month_names[12] = {"jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec"};
@@ -177,7 +177,7 @@ Result<SimpleConfig> decode_config(Slice input) {
   string hash(32, ' ');
   sha256(data_cbc.substr(0, 208), MutableSlice(hash));
   if (data_cbc.substr(208) != Slice(hash).substr(0, 16)) {
-    return Status::Error("sha256 mismatch");
+    return Status::Error("SHA256 mismatch");
   }
 
   TlParser len_parser{data_cbc};
@@ -253,7 +253,7 @@ ActorOwn<> get_simple_config_google_dns(Promise<SimpleConfigResult> promise, con
           res.r_config = [&]() -> Result<SimpleConfig> {
             TRY_RESULT(json, json_decode(http_query->content_));
             if (json.type() != JsonValue::Type::Object) {
-              return Status::Error("json error");
+              return Status::Error("JSON error");
             }
             auto &answer_object = json.get_object();
             TRY_RESULT(answer, get_json_object_field(answer_object, "Answer", JsonValue::Type::Array, false));
@@ -261,7 +261,7 @@ ActorOwn<> get_simple_config_google_dns(Promise<SimpleConfigResult> promise, con
             vector<string> parts;
             for (auto &v : answer_array) {
               if (v.type() != JsonValue::Type::Object) {
-                return Status::Error("json error");
+                return Status::Error("JSON error");
               }
               auto &data_object = v.get_object();
               TRY_RESULT(part, get_json_object_string_field(data_object, "data", false));
diff --git a/td/telegram/MessagesDb.cpp b/td/telegram/MessagesDb.cpp
index 521fa653b..e49290774 100644
--- a/td/telegram/MessagesDb.cpp
+++ b/td/telegram/MessagesDb.cpp
@@ -400,7 +400,7 @@ class MessagesDbImpl : public MessagesDbSyncInterface {
   Result<std::pair<DialogId, BufferSlice>> get_message_by_unique_message_id(
       ServerMessageId unique_message_id) override {
     if (!unique_message_id.is_valid()) {
-      return Status::Error("unique_message_id is invalid");
+      return Status::Error("Invalid unique_message_id");
     }
     SCOPE_EXIT {
       get_message_by_unique_message_id_stmt_.reset();
diff --git a/td/telegram/SecureStorage.cpp b/td/telegram/SecureStorage.cpp
index 18c04de02..e9a2b54c3 100644
--- a/td/telegram/SecureStorage.cpp
+++ b/td/telegram/SecureStorage.cpp
@@ -174,7 +174,7 @@ static uint8 secret_checksum(Slice secret) {
 
 Result<Secret> Secret::create(Slice secret) {
   if (secret.size() != 32) {
-    return Status::Error("wrong secret size");
+    return Status::Error("Wrong secret size");
   }
   uint32 checksum = secret_checksum(secret);
   if (checksum != 0) {
diff --git a/td/telegram/files/FileHashUploader.cpp b/td/telegram/files/FileHashUploader.cpp
index 1ac80e463..16c2280b5 100644
--- a/td/telegram/files/FileHashUploader.cpp
+++ b/td/telegram/files/FileHashUploader.cpp
@@ -39,7 +39,7 @@ Status FileHashUploader::init() {
   TRY_RESULT(fd, FileFd::open(local_.path_, FileFd::Read));
   TRY_RESULT(file_size, fd.get_size());
   if (file_size != size_) {
-    return Status::Error("size mismatch");
+    return Status::Error("Size mismatch");
   }
   fd_ = BufferedFd<FileFd>(std::move(fd));
   sha256_state_.init();
@@ -94,7 +94,7 @@ Status FileHashUploader::loop_sha() {
   fd_.get_poll_info().add_flags(PollFlags::Read());
   TRY_RESULT(read_size, fd_.flush_read(static_cast<size_t>(limit)));
   if (read_size != static_cast<size_t>(limit)) {
-    return Status::Error("unexpected end of file");
+    return Status::Error("Unexpected end of file");
   }
   while (true) {
     auto ready = fd_.input_buffer().prepare_read();
diff --git a/td/telegram/files/FileLoader.h b/td/telegram/files/FileLoader.h
index d1044f8b2..855012d9a 100644
--- a/td/telegram/files/FileLoader.h
+++ b/td/telegram/files/FileLoader.h
@@ -86,14 +86,14 @@ class FileLoader : public FileLoaderActor {
   virtual Callback *get_callback() = 0;
   virtual Result<PrefixInfo> on_update_local_location(const LocalFileLocation &location,
                                                       int64 file_size) TD_WARN_UNUSED_RESULT {
-    return Status::Error("unsupported");
+    return Status::Error("Unsupported");
   }
   virtual Result<bool> should_restart_part(Part part, NetQueryPtr &net_query) TD_WARN_UNUSED_RESULT {
     return false;
   }
 
   virtual Status process_check_query(NetQueryPtr net_query) {
-    return Status::Error("unsupported");
+    return Status::Error("Unsupported");
   }
   struct CheckInfo {
     bool need_check{false};
diff --git a/tdutils/td/utils/port/Stat.cpp b/tdutils/td/utils/port/Stat.cpp
index 96010bd5c..239594167 100644
--- a/tdutils/td/utils/port/Stat.cpp
+++ b/tdutils/td/utils/port/Stat.cpp
@@ -192,7 +192,7 @@ Result<MemStat> mem_stat() {
 
   if (KERN_SUCCESS !=
       task_info(mach_task_self(), TASK_BASIC_INFO, reinterpret_cast<task_info_t>(&t_info), &t_info_count)) {
-    return Status::Error("task_info failed");
+    return Status::Error("Call to task_info failed");
   }
   MemStat res;
   res.resident_size_ = t_info.resident_size;
@@ -296,7 +296,7 @@ Status cpu_stat_self(CpuStat &stat) {
       s++;
       pass_cnt++;
     } else {
-      return Status::Error("unexpected end of proc file");
+      return Status::Error("Unexpected end of proc file");
     }
   }
   return Status::OK();
diff --git a/test/secret.cpp b/test/secret.cpp
index 171d7da51..cab74359f 100644
--- a/test/secret.cpp
+++ b/test/secret.cpp
@@ -632,7 +632,7 @@ class Master : public Actor {
     int32 binlog_generation_ = 0;
     void sync_binlog(int32 binlog_generation, Promise<> promise) {
       if (binlog_generation != binlog_generation_) {
-        return promise.set_error(Status::Error("binlog generation mismatch"));
+        return promise.set_error(Status::Error("Binlog generation mismatch"));
       }
       binlog_->force_sync(std::move(promise));
     }
@@ -991,10 +991,10 @@ void FakeSecretChatContext::on_delete_messages(std::vector<int64> random_id, Pro
   promise.set_value(Unit());
 }
 void FakeSecretChatContext::on_flush_history(MessageId, Promise<> promise) {
-  promise.set_error(Status::Error("unsupported"));
+  promise.set_error(Status::Error("Unsupported"));
 }
 void FakeSecretChatContext::on_read_message(int64, Promise<> promise) {
-  promise.set_error(Status::Error("unsupported"));
+  promise.set_error(Status::Error("Unsupported"));
 }
 
 TEST(Secret, go) {