diff --git a/README.md b/README.md
index 28e18b6..8d4355c 100644
--- a/README.md
+++ b/README.md
@@ -103,12 +103,13 @@ If you've used [Swagger](http://swagger.io/specification) before, then the synta
 
 Take special note of the __run_test!__ method that's called within each response block. This tells rswag to create and execute a corresponding example. It builds and submits a request based on parameter descriptions and corresponding values that have been provided using the rspec "let" syntax. For example, the "post" description in the example above specifies a "body" parameter called "blog". It also lists 2 different responses. For the success case (i.e. the 201 response), notice how "let" is used to set the blog parameter to a value that matches the provided schema. For the failure case (i.e. the 422 response), notice how it's set to a value that does not match the provided schema. When the test is executed, rswag also validates the actual response code and, where applicable, the response body against the provided [JSON Schema](http://json-schema.org/documentation.html).
 
-If you want to do additional validation on the JSON response, pass a block to the __run_test!__ method:
+If you want to do additional validation on the response, pass a block to the __run_test!__ method:
 
 ```ruby
 response '201', 'blog created' do
-  run_test! do |body|
-    expect(body['title']).to eq('foo')
+  run_test! do |response|
+    data = JSON.parse(response)
+    expect(data['title']).to eq('foo')
   end
 end
 ```
diff --git a/rswag-specs/lib/rswag/specs/response_validator.rb b/rswag-specs/lib/rswag/specs/response_validator.rb
index 946c53d..2e75097 100644
--- a/rswag-specs/lib/rswag/specs/response_validator.rb
+++ b/rswag-specs/lib/rswag/specs/response_validator.rb
@@ -48,7 +48,7 @@ module Rswag
           raise UnexpectedResponse, "Expected response body to match schema: #{ex.message}"
         end
 
-        block.call(JSON.parse(body)) if block_given?
+        block.call(body) if block_given?
       end
     end
 
diff --git a/rswag-specs/spec/rswag/specs/response_validator_spec.rb b/rswag-specs/spec/rswag/specs/response_validator_spec.rb
index 02316c7..bf1bba6 100644
--- a/rswag-specs/spec/rswag/specs/response_validator_spec.rb
+++ b/rswag-specs/spec/rswag/specs/response_validator_spec.rb
@@ -46,7 +46,8 @@ module Rswag
           context "'block' provided" do
             let(:call) do
               subject.validate!(response) do |body|
-                expect(body['text']).to eq('Some comment')
+                data = JSON.parse(body)
+                expect(data['text']).to eq('Some comment')
               end
             end