diff --git a/lib/yandex-checkout/payment.rb b/lib/yandex-checkout/payment.rb
index 14908c8..c5a31f1 100644
--- a/lib/yandex-checkout/payment.rb
+++ b/lib/yandex-checkout/payment.rb
@@ -15,44 +15,21 @@ module YandexCheckout
       path { "/#{payment_id}" }
 
       response(200) { |*res| Entity::Payment.build(*res) }
-
       response(400, 404) { |*res| Error.build(*res) }
-      # Parses json response, wraps it into model with [#error] and raises
-      # an exception where [ResponseError#response] contains the model instance
-
-      # response(400, 422) do |(status, *)|
-      #   raise "#{status}: Record invalid"
-      # end
-
-      # response(404) do |(_status, *)|
-      #   p 'Record Not Found'
-      #   # raise "#{status}: Record not found"
-      # end
     end
 
     operation :create do
       option :payment
-      option :idempotency_key, optional: true
+      option :idempotency_key, proc(&:to_s)
 
       http_method :post
 
-      # path { 'payments' }
-      # query { { params: params } }
       format 'json'
-      headers 'Idempotence-Key' => '244afbdc-000f-5000-a000-12526186ce10'
+      headers { { 'Idempotence-Key' => idempotency_key } }
       body { payment }
 
-      # response 200 do |_status, _headers, body|
-      #   p JSON.parse(*body)
-      # end
       response(200) { |*res| Entity::Payment.build(*res) }
       response(400) { |*res| Error.build(*res) }
-      # Parses json response, wraps it into model with [#error] and raises
-      # an exception where [ResponseError#response] contains the model instance
-
-      # response(400, 422) do |(status, *)|
-      #   raise "#{status}: Record invalid"
-      # end
     end
 
     operation :capture do
@@ -64,7 +41,7 @@ module YandexCheckout
       path { "/#{payment_id}/capture" }
 
       format 'json'
-      headers 'Idempotence-Key' => '244afbdc-000f-5000-a000-12526186ce10'
+      headers { { 'Idempotence-Key' => idempotency_key } }
 
       response(200) { |*res| Entity::Payment.build(*res) }
       response(400) { |*res| Error.build(*res) }
@@ -79,7 +56,7 @@ module YandexCheckout
       path { "/#{payment_id}/cancel" }
 
       format 'json'
-      headers 'Idempotence-Key' => '244afbdc-000f-5000-a000-12526186ce10'
+      headers { { 'Idempotence-Key' => idempotency_key } }
 
       response(200) { |*res| Entity::Payment.build(*res) }
       response(400) { |*res| Error.build(*res) }
diff --git a/spec/yandex-checkout/payment_spec.rb b/spec/yandex-checkout/payment_spec.rb
index 71e7872..acc6329 100644
--- a/spec/yandex-checkout/payment_spec.rb
+++ b/spec/yandex-checkout/payment_spec.rb
@@ -3,14 +3,14 @@
 RSpec.describe YandexCheckout::Payment do
   describe '#create' do
     let(:settings) { { shop_id: 'SHOP_ID', api_key: 'API_KEY' } }
-    let(:idempotence_key) { 12_345 }
+    let(:idempotency_key) { 12_345 }
     let(:payment) { described_class.new(settings) }
     let(:params) { { payment: File.read('spec/fixtures/payment.json') } }
     let(:url) { 'https://payment.yandex.net/api/v3/payments' }
     let(:body) { File.read('spec/fixtures/payment_response.json') }
 
     before  { stub_request(:any, //).to_return(body: body) }
-    subject { payment.create(payment: params, idempotency_key: idempotence_key) }
+    subject { payment.create(payment: params, idempotency_key: idempotency_key) }
 
     it 'sends a request' do
       subject