diff --git a/Gemfile.lock b/Gemfile.lock
index cec377c..f15a4a7 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    omniai (1.8.0)
+    omniai (1.8.1)
       event_stream_parser
       http
       zeitwerk
diff --git a/lib/omniai/tool.rb b/lib/omniai/tool.rb
index aa48c34..6064931 100644
--- a/lib/omniai/tool.rb
+++ b/lib/omniai/tool.rb
@@ -53,7 +53,10 @@ def initialize(function, name:, description: nil, parameters: nil)
     #   #     parameters: {
     #   #       type: 'object',
     #   #       properties: {
-    #   #         n: OmniAI::Tool::Property.integer(description: 'The nth Fibonacci number to calculate')
+    #   #         n: {
+    #   #           description: 'The nth Fibonacci number to calculate')
+    #   #           type: 'integer'
+    #   #         }
     #   #       },
     #   #       required: ['n']
     #   #     }
@@ -71,7 +74,7 @@ def serialize(context: nil)
         function: {
           name: @name,
           description: @description,
-          parameters: @parameters&.prepare,
+          parameters: @parameters.is_a?(Tool::Parameters) ? @parameters.serialize : @parameters,
         }.compact,
       }
     end
@@ -83,7 +86,7 @@ def serialize(context: nil)
     # @param args [Hash]
     # @return [String]
     def call(args = {})
-      @function.call(**(@parameters ? @parameters.parse(args) : args))
+      @function.call(**(@parameters.is_a?(Tool::Parameters) ? @parameters.parse(args) : args))
     end
   end
 end
diff --git a/lib/omniai/tool/parameters.rb b/lib/omniai/tool/parameters.rb
index b615ea9..65bbd28 100644
--- a/lib/omniai/tool/parameters.rb
+++ b/lib/omniai/tool/parameters.rb
@@ -24,10 +24,10 @@ def initialize(type: Type::OBJECT, properties: {}, required: [])
       end
 
       # @return [Hash]
-      def prepare
+      def serialize
         {
           type: @type,
-          properties: @properties.transform_values(&:prepare),
+          properties: @properties.transform_values(&:serialize),
           required: @required,
         }.compact
       end
diff --git a/lib/omniai/tool/property.rb b/lib/omniai/tool/property.rb
index 598af8f..70a5555 100644
--- a/lib/omniai/tool/property.rb
+++ b/lib/omniai/tool/property.rb
@@ -60,7 +60,7 @@ def initialize(type:, description: nil, enum: nil)
       end
 
       # @example
-      #   property.prepare
+      #   property.serialize
       #   # {
       #   #   type: 'string',
       #   #   description: 'The unit (e.g. "fahrenheit" or "celsius").'
@@ -68,7 +68,7 @@ def initialize(type:, description: nil, enum: nil)
       #   # }
       #
       # @return [Hash]
-      def prepare
+      def serialize
         {
           type: @type,
           description: @description,
diff --git a/lib/omniai/version.rb b/lib/omniai/version.rb
index 504d78d..aa85da8 100644
--- a/lib/omniai/version.rb
+++ b/lib/omniai/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module OmniAI
-  VERSION = '1.8.0'
+  VERSION = '1.8.1'
 end
diff --git a/spec/omniai/tool/parameters_spec.rb b/spec/omniai/tool/parameters_spec.rb
index 2ce97da..12f76f5 100644
--- a/spec/omniai/tool/parameters_spec.rb
+++ b/spec/omniai/tool/parameters_spec.rb
@@ -11,9 +11,9 @@
 
   let(:required) { %i[n] }
 
-  describe '#prepare' do
+  describe '#serialize' do
     it 'converts the parameters to a hash' do
-      expect(parameters.prepare).to eq({
+      expect(parameters.serialize).to eq({
         type: 'object',
         properties: {
           n: { type: 'integer', description: 'The nth number to calculate.' },
diff --git a/spec/omniai/tool/property_spec.rb b/spec/omniai/tool/property_spec.rb
index b640821..617f171 100644
--- a/spec/omniai/tool/property_spec.rb
+++ b/spec/omniai/tool/property_spec.rb
@@ -31,9 +31,9 @@
     it { expect(property.type).to eq('number') }
   end
 
-  describe '#prepare' do
+  describe '#serialize' do
     it 'converts the property to a hash' do
-      expect(property.prepare).to eq({
+      expect(property.serialize).to eq({
         type: 'string',
         description: 'The unit (e.g. "fahrenheit" or "celsius")',
         enum: %w[fahrenheit celsius],