diff --git a/src/main.cc b/src/main.cc
index 59afda4..d826029 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -7,8 +7,8 @@ static void show_usage(const bool include_help)
 {
     static const auto usage =
         "Usage: opustags --help\n"
-        "       opustags [OPTIONS] FILE\n"
-        "       opustags OPTIONS FILE -o FILE\n";
+        "       opustags [OPTIONS] INPUT\n"
+        "       opustags [OPTIONS] -o OUTPUT INPUT\n";
 
     static const auto help =
         "Options:\n"
@@ -45,6 +45,7 @@ int main(int argc, char **argv)
         }
 
         std::cout << "Working...\n";
+        std::cout << "Input path: " << options.path_in << "\n";
     } catch (const std::exception &e) {
         std::cerr << e.what();
         return EXIT_FAILURE;
diff --git a/src/options.cc b/src/options.cc
index 9d343b2..77278c6 100644
--- a/src/options.cc
+++ b/src/options.cc
@@ -120,5 +120,13 @@ Options opustags::parse_args(const int argc, char **argv)
         }
     }
 
+    if (optind == argc || argv[optind] == NULL) {
+        throw ArgumentError("Missing input path");
+    }
+
+    options.path_in = argv[optind];
+    if (options.path_in.empty())
+        throw ArgumentError("Input path cannot be empty");
+
     return options;
 }
diff --git a/src/options.h b/src/options.h
index 083b0ed..6064a52 100644
--- a/src/options.h
+++ b/src/options.h
@@ -16,6 +16,7 @@ namespace opustags
         bool set_all;
 
         bool in_place;
+        std::string path_in;
         std::string path_out;
 
         CompositeTagsHandler tags_handler;
diff --git a/tests/options_test.cc b/tests/options_test.cc
index a008d77..9aa39e9 100644
--- a/tests/options_test.cc
+++ b/tests/options_test.cc
@@ -16,13 +16,16 @@ static std::unique_ptr<char[]> string_to_uptr(const std::string &str)
     return ret;
 }
 
-static Options retrieve_options(std::vector<std::string> args)
+static Options retrieve_options(
+    std::vector<std::string> args, bool fake_input_path = true)
 {
     // need to pass non-const char*, but we got const objects. make copies
     std::vector<std::unique_ptr<char[]>> arg_holders;
     arg_holders.push_back(string_to_uptr("fake/path/to/program"));
     for (size_t i = 0; i < args.size(); i++)
         arg_holders.push_back(string_to_uptr(args[i]));
+    if (fake_input_path)
+        arg_holders.push_back(string_to_uptr("fake/path/to/input"));
 
     auto plain_args = std::make_unique<char*[]>(arg_holders.size());
     for (size_t i = 0; i < arg_holders.size(); i++)
@@ -78,10 +81,15 @@ TEST_CASE("option parsing", "[options]")
         REQUIRE(retrieve_options({"-iABC"}).path_out == "ABC");
     }
 
+    SECTION("input") {
+        REQUIRE_THROWS(retrieve_options({}, false));
+        REQUIRE_THROWS(retrieve_options({""}, false));
+        REQUIRE(retrieve_options({"input"}, false).path_in == "input");
+    }
+
     SECTION("--output") {
         REQUIRE(retrieve_options({"--output", "ABC"}).path_out == "ABC");
         REQUIRE(retrieve_options({"-o", "ABC"}).path_out == "ABC");
-        REQUIRE_THROWS(retrieve_options({"--delete", "invalid="}));
     }
 
     SECTION("--delete-all") {