1 files changed, 10 insertions, 10 deletions
diff --git a/toolsrc/src/commands_installation.cpp b/toolsrc/src/commands_installation.cpp
index 2890184fb..9eacfedcc 100644
--- a/toolsrc/src/commands_installation.cpp
+++ b/toolsrc/src/commands_installation.cpp
@@ -65,9 +65,11 @@ namespace vcpkg
 
     void install_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
     {
+        static const std::string example = create_example_string("install zlib zlib:x64-windows curl boost");
+        args.check_min_arg_count(1, example.c_str());
         StatusParagraphs status_db = database_load_check(paths);
 
-        std::vector<package_spec> specs = args.parse_all_arguments_as_package_specs(default_target_triplet);
+        std::vector<package_spec> specs = vcpkg_cmd_arguments::check_and_get_package_specs(args.command_arguments, default_target_triplet, example.c_str());
         std::vector<package_spec> install_plan = Dependencies::create_dependency_ordered_install_plan(paths, specs, status_db);
         Checks::check_exit(!install_plan.empty(), "Install plan cannot be empty");
         std::string specs_string = to_string(install_plan[0]);
@@ -120,13 +122,15 @@ namespace vcpkg
 
     void build_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
     {
+        static const std::string example = create_example_string("build zlib:x64-windows");
+
         // Installing multiple packages leads to unintuitive behavior if one of them depends on another.
-        // Allowing only 1 package for now. 
-        args.check_max_args(1);
+        // Allowing only 1 package for now.
 
+        args.check_exact_arg_count(1, example.c_str());
         StatusParagraphs status_db = database_load_check(paths);
 
-        const package_spec spec = args.parse_all_arguments_as_package_specs(default_target_triplet).at(0);
+        const package_spec spec = vcpkg_cmd_arguments::check_and_get_package_spec(args.command_arguments.at(0), default_target_triplet, example.c_str());
         std::unordered_set<package_spec> unmet_dependencies = Dependencies::find_unmet_dependencies(paths, spec, status_db);
         if (!unmet_dependencies.empty())
         {
@@ -148,12 +152,8 @@ namespace vcpkg
 
     void build_external_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
     {
-        if (args.command_arguments.size() != 2)
-        {
-            System::println(System::color::error, "Error: buildexternal requires the package name and the directory containing the CONTROL file");
-            print_example(R"(buildexternal mylib C:\path\to\mylib\)");
-            exit(EXIT_FAILURE);
-        }
+        static const std::string example = create_example_string(R"(build_external zlib2 C:\path\to\dir\with\controlfile\)");
+        args.check_exact_arg_count(2, example.c_str());
 
         expected<package_spec> current_spec = package_spec::from_string(args.command_arguments[0], default_target_triplet);
         if (auto spec = current_spec.get())