When to use it: Once, to set up ChatGPT (or Claude) so it works with you instead of forgetting you. About 15 minutes.
When to avoid it: Don’t over-tune. Set these once and move on. Adjusting settings isn’t the same as getting work done.
The five settings:
- Memory. Lets the model remember facts across chats. Useful for stable context like your role and your style. Turn it on, then glance at what it’s storing now and then; it sometimes saves the wrong thing.
- Custom instructions. The “always answer me like this” box. Set your role and how you want answers. Honest limit: custom instructions get ignored mid-chat more than you’d like, which is why I let my text-replacement tags (item 2) carry the real load.
- Projects. Free in ChatGPT and Claude. A workspace that holds your context profile and files. This is where I keep my own work-context profile (item 6).
- Temporary chat. A chat that doesn’t save to history or memory. Use it for anything you don’t want stored, or to test a prompt without filling your memory with clutter.
- File uploads. Drop a document in and ask about it instead of pasting from memory. Grounds the answer in the actual file. I lean on this for document work, then spot-check names, numbers, dates, and quotes against the original.
Exact steps: Open settings. Turn on Memory. Fill in Custom instructions (role plus answer style). Create one Project. Note where Temporary chat lives. Try one file upload.
Expected result: The model starts from “knows roughly who you are” instead of a blank slate, and you’ve got a safe space (temporary chat) and a grounded space (uploads and Projects).
Where it breaks: Custom instructions are the least reliable of the five; don’t lean on them for anything critical. Memory can store something wrong and apply it later without flagging it. Uploaded files get summarized, so the model can still misread a number inside one.
What to check before using it: What Memory currently holds (delete anything wrong), and that nothing sensitive sits in custom instructions or an uploaded file you wouldn’t want stored.