diff --git a/configs.go b/configs.go
index aff0cd9..5524207 100644
--- a/configs.go
+++ b/configs.go
@@ -349,6 +349,7 @@ func (config AudioConfig) method() string {
 // DocumentConfig contains information about a SendDocument request.
 type DocumentConfig struct {
 	BaseFile
+	Caption  string
 }
 
 // values returns a url.Values representation of DocumentConfig.
@@ -360,6 +361,10 @@ func (config DocumentConfig) values() (url.Values, error) {
 
 	v.Add(config.name(), config.FileID)
 
+	if config.Caption != "" {
+		v.Add("caption", config.Caption)
+	}
+
 	return v, nil
 }
 
diff --git a/telegram-bot-api.iml b/telegram-bot-api.iml
new file mode 100644
index 0000000..8c53b5c
--- /dev/null
+++ b/telegram-bot-api.iml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="GO_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="GOPATH &lt;telegram-bot-api&gt;" level="project" />
+  </component>
+</module>
\ No newline at end of file
diff --git a/types.go b/types.go
index c852f86..d41dd02 100644
--- a/types.go
+++ b/types.go
@@ -358,9 +358,9 @@ type InlineKeyboardButton struct {
 	Text                         string        `json:"text"`
 	URL                          *string       `json:"url,omitempty"`                    // optional
 	CallbackData                 *string       `json:"callback_data,omitempty"`          // optional
-	SwitchInlineQuery            *string       `json:"switch_inline_query,omitempty"`    // optional
-	SwitchInlineQueryCurrentChat *string       `json:"switch_inline_query_current_chat"` // optional
-	CallbackGame                 *CallbackGame `json:"callback_game"`                    // optional
+	SwitchInlineQuery            *string       `json:"switch_inline_query,omitempty,omitempty"`    // optional
+	SwitchInlineQueryCurrentChat *string       `json:"switch_inline_query_current_chat,omitempty"` // optional
+	CallbackGame                 *CallbackGame `json:"callback_game,omitempty"`                    // optional
 }
 
 // CallbackQuery is data sent when a keyboard button with callback data
@@ -607,8 +607,8 @@ type ChosenInlineResult struct {
 // as an inline query result.
 type InputTextMessageContent struct {
 	Text                  string `json:"message_text"`
-	ParseMode             string `json:"parse_mode"`
-	DisableWebPagePreview bool   `json:"disable_web_page_preview"`
+	ParseMode             string `json:"parse_mode,omitempty"`
+	DisableWebPagePreview bool   `json:"disable_web_page_preview,omitempty"`
 }
 
 // InputLocationMessageContent contains a location for displaying