Short answerAnswers differ because the model, the way files are searched, the settings and the available tools all change. You can get close by tuning instructions and testing, but identical behavior is not a realistic promise.
What changes
| Factor | Why it matters |
|---|---|
| Model | Different models write, reason and refuse differently |
| Retrieval | Each platform searches files differently |
| Settings | Temperature, length limits and capability settings may not transfer (OpenAI lists the selected model and capability settings as not carrying over) |
| Tools | No browsing, images or Actions unless rebuilt |
What to do
- Decide which differences matter to your users.
- Tune instructions for those.
- Accept small wording differences that do not change facts.
- Document known limits for your users.
See what transfers and testing.
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