diff --git a/src/compiler/commandLineParser.ts b/src/compiler/commandLineParser.ts
index 2e2c5c0bdb6..3a4d5c6b1f7 100644
--- a/src/compiler/commandLineParser.ts
+++ b/src/compiler/commandLineParser.ts
@@ -212,8 +212,8 @@ namespace ts {
             shortName: "p",
             type: "string",
             isFilePath: true,
-            description: Diagnostics.Compile_the_project_in_the_given_directory,
-            paramType: Diagnostics.DIRECTORY
+            description: Diagnostics.Compile_the_project_given_the_path_to_its_configuration_file_or_to_a_folder_with_a_tsconfig_json,
+            paramType: Diagnostics.FILE_OR_DIRECTORY
         },
         {
             name: "removeComments",
@@ -517,7 +517,7 @@ namespace ts {
                 include: typeAcquisition.include || [],
                 exclude: typeAcquisition.exclude || []
             };
-           return result;
+            return result;
         }
         return typeAcquisition;
     }
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index ec5ca292b99..6bdf9932fca 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2513,7 +2513,7 @@
         "category": "Message",
         "code": 6019
     },
-    "Compile the project in the given directory.": {
+    "Compile the project given the path to its configuration file, or to a folder with a 'tsconfig.json'": {
         "category": "Message",
         "code": 6020
     },
@@ -2573,6 +2573,10 @@
         "category": "Message",
         "code": 6039
     },
+    "FILE OR DIRECTORY": {
+        "category": "Message",
+        "code": 6040
+    },
     "Compilation complete. Watching for file changes.": {
         "category": "Message",
         "code": 6042