diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 00000000..b58b603f
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,5 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 00000000..8e1eddec
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,50 @@
+<component name="ProjectCodeStyleConfiguration">
+  <code_scheme name="Project" version="173">
+    <JSCodeStyleSettings version="0">
+      <option name="USE_SEMICOLON_AFTER_STATEMENT" value="false" />
+      <option name="FORCE_SEMICOLON_STYLE" value="true" />
+      <option name="SPACE_BEFORE_FUNCTION_LEFT_PARENTH" value="false" />
+      <option name="USE_DOUBLE_QUOTES" value="false" />
+      <option name="FORCE_QUOTE_STYlE" value="true" />
+      <option name="ENFORCE_TRAILING_COMMA" value="Remove" />
+      <option name="SPACES_WITHIN_OBJECT_LITERAL_BRACES" value="true" />
+      <option name="SPACES_WITHIN_IMPORTS" value="true" />
+    </JSCodeStyleSettings>
+    <TypeScriptCodeStyleSettings version="0">
+      <option name="USE_SEMICOLON_AFTER_STATEMENT" value="false" />
+      <option name="FORCE_SEMICOLON_STYLE" value="true" />
+      <option name="SPACE_AFTER_DOTS_IN_REST_PARAMETER" value="true" />
+      <option name="SPACE_BEFORE_FUNCTION_LEFT_PARENTH" value="false" />
+      <option name="USE_DOUBLE_QUOTES" value="false" />
+      <option name="FORCE_QUOTE_STYlE" value="true" />
+      <option name="ENFORCE_TRAILING_COMMA" value="Remove" />
+      <option name="SPACES_WITHIN_OBJECT_LITERAL_BRACES" value="true" />
+      <option name="SPACES_WITHIN_IMPORTS" value="true" />
+      <option name="USE_CHAINED_CALLS_GROUP_INDENTS" value="true" />
+      <option name="IMPORT_SORT_MODULE_NAME" value="true" />
+    </TypeScriptCodeStyleSettings>
+    <codeStyleSettings language="JavaScript">
+      <option name="SOFT_MARGINS" value="80" />
+      <indentOptions>
+        <option name="INDENT_SIZE" value="2" />
+        <option name="CONTINUATION_INDENT_SIZE" value="2" />
+        <option name="TAB_SIZE" value="2" />
+      </indentOptions>
+    </codeStyleSettings>
+    <codeStyleSettings language="TypeScript">
+      <option name="KEEP_BLANK_LINES_IN_CODE" value="1" />
+      <option name="SPACE_BEFORE_COLON" value="false" />
+      <option name="IF_BRACE_FORCE" value="1" />
+      <option name="DOWHILE_BRACE_FORCE" value="1" />
+      <option name="WHILE_BRACE_FORCE" value="1" />
+      <option name="FOR_BRACE_FORCE" value="1" />
+      <option name="SOFT_MARGINS" value="80" />
+      <indentOptions>
+        <option name="INDENT_SIZE" value="2" />
+        <option name="CONTINUATION_INDENT_SIZE" value="2" />
+        <option name="TAB_SIZE" value="2" />
+        <option name="SMART_TABS" value="true" />
+      </indentOptions>
+    </codeStyleSettings>
+  </code_scheme>
+</component>
\ No newline at end of file
diff --git a/.idea/codeStyles/codeStyleConfig.xml b/.idea/codeStyles/codeStyleConfig.xml
new file mode 100644
index 00000000..79ee123c
--- /dev/null
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -0,0 +1,5 @@
+<component name="ProjectCodeStyleConfiguration">
+  <state>
+    <option name="USE_PER_PROJECT_SETTINGS" value="true" />
+  </state>
+</component>
\ No newline at end of file
diff --git a/.idea/inspectionProfiles/Project_Default.xml b/.idea/inspectionProfiles/Project_Default.xml
new file mode 100644
index 00000000..df7825df
--- /dev/null
+++ b/.idea/inspectionProfiles/Project_Default.xml
@@ -0,0 +1,6 @@
+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="TsLint" enabled="true" level="WARNING" enabled_by_default="true" />
+  </profile>
+</component>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 00000000..28a804d8
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="JavaScriptSettings">
+    <option name="languageLevel" value="ES6" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 00000000..98b50d0f
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/routing-controllers-openapi.iml" filepath="$PROJECT_DIR$/.idea/routing-controllers-openapi.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/routing-controllers-openapi.iml b/.idea/routing-controllers-openapi.iml
new file mode 100644
index 00000000..24643cc3
--- /dev/null
+++ b/.idea/routing-controllers-openapi.iml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="WEB_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$">
+      <excludeFolder url="file://$MODULE_DIR$/.tmp" />
+      <excludeFolder url="file://$MODULE_DIR$/temp" />
+      <excludeFolder url="file://$MODULE_DIR$/tmp" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 00000000..94a25f7f
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/src/generateSpec.ts b/src/generateSpec.ts
index 1090ca76..2af799d7 100644
--- a/src/generateSpec.ts
+++ b/src/generateSpec.ts
@@ -300,8 +300,13 @@ function getParamSchema(
   param: ParamMetadataArgs
 ): oa.SchemaObject | oa.ReferenceObject {
   const { explicitType, index, object, method } = param
-
-  const type = Reflect.getMetadata('design:paramtypes', object, method)[index]
+  const reflectedTypes = Reflect.getMetadata(
+    'design:paramtypes',
+    object,
+    method
+  )
+  if (reflectedTypes.length <= index) return {}
+  const type = reflectedTypes[index]
   if (_.isFunction(type) && type.name === 'Array') {
     const items = explicitType
       ? { $ref: '#/components/schemas/' + explicitType.name }