Typo (openai#1243)

Author: royziv11

examples/Developing_hallucination_guardrails.ipynb

@@ -607,7 +607,7 @@
     "- It is important to keep relevant terms such as knowledge base articles, assistants, and users consistent across the prompt\n",
     "- If we begin to use phrases such as assistant vs agent, the model could get confused\n",
     "3. Start with the most advanced model\n",
-    "- There is a cost vs quality trade-off when using the most advanced models. Although GPT-4o may be a more expensive to start, but it important to start with the most advanced so we can ensure a high degree of accuracy\n",
+    "- There is a cost vs quality trade-off when using the most advanced models. Although GPT-4o may be more expensive, it is important to start with the most advanced model so we can ensure a high degree of accuracy\n",
     "- Once we have thoroughly tested out the guardrail and are confident in its performance, we can look to reducing cost by tuning it down to gpt-3.5-turbo\n",
     "4. Evaluate each sentence independently and the entire response as a whole\n",
     "- If the agent returns a long response, it can be useful to break down the response to individual sentences and evaluate them independently\n",