diff --git a/lib/ruby_llm/providers/openai/capabilities.rb b/lib/ruby_llm/providers/openai/capabilities.rb
index 37c320da8..317c24ea2 100644
--- a/lib/ruby_llm/providers/openai/capabilities.rb
+++ b/lib/ruby_llm/providers/openai/capabilities.rb
@@ -224,12 +224,12 @@ def special_prefix_format(prefix)
         end
 
         def self.normalize_temperature(temperature, model_id)
-          if model_id.match?(/^(o\d|gpt-5)/)
-            RubyLLM.logger.debug "Model #{model_id} requires temperature=1.0, ignoring provided value"
-            1.0
-          elsif model_id.match?(/-search/)
+          if model_id.match?(/-search/)
             RubyLLM.logger.debug "Model #{model_id} does not accept temperature parameter, removing"
             nil
+          elsif model_id.match?(/^(o\d|gpt-5)/)
+            RubyLLM.logger.debug "Model #{model_id} requires temperature=1.0, ignoring provided value"
+            1.0
           else
             temperature
           end
diff --git a/spec/ruby_llm/providers/open_ai/capabilities_spec.rb b/spec/ruby_llm/providers/open_ai/capabilities_spec.rb
index 2eede6708..5c00bee29 100644
--- a/spec/ruby_llm/providers/open_ai/capabilities_spec.rb
+++ b/spec/ruby_llm/providers/open_ai/capabilities_spec.rb
@@ -10,8 +10,14 @@
       end
     end
 
+    it 'forces temperature to 1.0 for GPT-5 models' do
+      %w[gpt-5 gpt-5-mini gpt-5-nano].each do |model|
+        expect(described_class.normalize_temperature(0.7, model)).to eq(1.0)
+      end
+    end
+
     it 'returns nil for search preview models' do
-      %w[gpt-4o-search-preview gpt-4o-mini-search-preview].each do |model|
+      %w[gpt-4o-search-preview gpt-4o-mini-search-preview gpt-5-search-api].each do |model|
         expect(described_class.normalize_temperature(0.7, model)).to be_nil
       end
     end