ChatGPT: Memory Is a Cache, Custom Instructions Are Config (Where to Put Your Rules)
If you write software, you already know the difference between a config file and a cache. A config file is something you wrote, you can read it, and it behaves the same way every time. A cache is something the system fills in for itself, it changes as things change, and you should never trust it as your source of truth. That is the cleanest way I have found to explain ChatGPT custom instructions…
Custom instructions for ChatGPT act like configuration files in software development. They are direct guidance you provide, remain the same each time, and can be read directly in Settings under Personalization. Users on all plans can utilize this feature, with longer character limits available for Pro and higher tiers. Custom instructions should contain stable preferences like role, tone, and guidelines on avoiding certain mistakes.
Memory in ChatGPT functions more like a cache. When enabled, it recalls relevant data from past chats, saved memories, custom instructions, and connected apps (depending on plan and region). Memory does not retain every detail of every conversation but selects what seems pertinent, which may evolve over time. Users can review what ChatGPT remembers in Settings via Personalization and Memory. Turning off memory does not delete past chats.
For business purposes, custom instructions should handle stable rules, while memory serves as a helpful background context. Both can be viewed in chats, with Sources links indicating which contributed to the response. OpenAI notes that Sources might not account for all factors, so treat them as hints.
Certain sensitive information, such as prices, dates, client names, or policies, should not rely on memory to remain accurate. If a fact must be precise, paste it directly into the chat. Caches can become outdated, so if a specific detail is critical, it may be better to use a Project with its own set of project instructions. These project instructions only apply within that project and override global custom instructions.
Temporary chats allow users to disable existing memories and custom instructions, ensuring a fresh start without lingering data. However, even in temporary chats, OpenAI may use the conversation data to improve its models. Users can opt out of this practice in Data controls. Confidential information should still be avoided in these instructions, as OpenAI may use the content for model improvement.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
