diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 2.0.2
+* add json to send ToJson instances with auto 'application/json' content type.
+
 # 2.0.1
 * document Data.Param.File
 * expose Control.Monad.Apiary.Action.getReqBodyJSON
diff --git a/apiary.cabal b/apiary.cabal
--- a/apiary.cabal
+++ b/apiary.cabal
@@ -1,5 +1,5 @@
 name:                apiary
-version:             2.0.1.1
+version:             2.0.2
 synopsis:            Simple and type safe web framework that generate web API documentation.
 description:
   Simple and type safe web framework that can be automatically generate API documentation.
diff --git a/src/Control/Monad/Apiary/Action.hs b/src/Control/Monad/Apiary/Action.hs
--- a/src/Control/Monad/Apiary/Action.hs
+++ b/src/Control/Monad/Apiary/Action.hs
@@ -20,6 +20,7 @@
     , bytes, lazyBytes
     , text,  lazyText
     , showing
+    , json
     , string, char
     , appendBuilder
     , appendBytes, appendLazyBytes
diff --git a/src/Control/Monad/Apiary/Action/Internal.hs b/src/Control/Monad/Apiary/Action/Internal.hs
--- a/src/Control/Monad/Apiary/Action/Internal.hs
+++ b/src/Control/Monad/Apiary/Action/Internal.hs
@@ -34,6 +34,7 @@
     , bytes, lazyBytes
     , text,  lazyText
     , showing
+    , json
     , string, char
     , appendBuilder
     , appendBytes, appendLazyBytes
@@ -139,7 +140,7 @@
 import qualified Data.Text.Lazy as TL
 import qualified Data.Vault.Lazy as V
 import Data.Word (Word64)
-import Data.Aeson (FromJSON)
+import Data.Aeson (FromJSON, ToJSON)
 import qualified Data.Aeson as JSON
 
 data ApiaryConfig = ApiaryConfig
@@ -764,6 +765,12 @@
 -- | set response body from show. encoding UTF-8. since 0.15.2.
 showing :: (Monad m, Show a) => a -> ActionT exts prms m ()
 showing = builder . B.fromShow
+
+-- | set response body from 'ToJSON' with content-type set to @application/json@. since 2.0.2
+json :: (Monad m, ToJSON a) => a -> ActionT exts prms m ()
+json x = do
+    contentType "application/json"
+    lazyBytes (JSON.encode x)
 
 -- | set response body from string. encoding UTF-8. since 0.15.2.
 string :: Monad m => String -> ActionT exts prms m ()
diff --git a/src/Web/Apiary.hs b/src/Web/Apiary.hs
--- a/src/Web/Apiary.hs
+++ b/src/Web/Apiary.hs
@@ -60,6 +60,7 @@
     , bytes, lazyBytes
     , text,  lazyText
     , showing
+    , json
     , string, char
     , appendBuilder
     , appendBytes, appendLazyBytes