diff --git a/evoprompt/optimization.py b/evoprompt/optimization.py
index 81538709c460da09134e5fbe3841e1595105986b..095beaa78a663c0af56c2e8dfa15a89083175c6b 100644
--- a/evoprompt/optimization.py
+++ b/evoprompt/optimization.py
@@ -93,8 +93,8 @@ class ResponseEditor(App):
         return self.text_area.text
 
 
-@log_calls("Paraphrasing prompts")
-def paraphrase_prompts(
+@log_calls("Paraphrasing prompt")
+def paraphrase_prompt(
     model: LLMModel,
     prompt: str,
     n: int,
@@ -112,7 +112,8 @@ def paraphrase_prompts(
         num_tries += 1
         paraphrase, _, _, usage = model.create_completion(
             system_message=PARAPHRASE_PROMPT,
-            prompt=f"Instruction: {prompt}",
+            prompt=prompt,
+            enforce_randomness=True,
         )
         total_usage += usage
         if "<prompt>" in paraphrase:
@@ -200,7 +201,7 @@ class PromptOptimization:
         # fill up the rest with paraphrases of the top prompts
         promptindex_to_paraphrase = 0
         while len(initial_population) < num_initial_prompts:
-            paraphrases, paraphrase_usage = paraphrase_prompts(
+            paraphrases, paraphrase_usage = paraphrase_prompt(
                 self.evolution_model,
                 top_prompts[promptindex_to_paraphrase],
                 n=1,