Custom Instructions
Custom Instructions are persistent configuration settings in ChatGPT that allow users to specify how the AI should behave across all conversations. Rather than repeating context, preferences, or role information with each new chat, users define these details once in their account settings, and ChatGPT applies them automatically to subsequent interactions. This reduces redundancy and helps maintain consistent behavior and response style throughout multiple conversations.
Configuration
Users configure Custom Instructions through their ChatGPT account settings by providing two main inputs: information about themselves and how they want ChatGPT to respond. The first section allows users to share relevant context such as their role, expertise level, or organizational affiliation. The second section specifies preferences for tone, format, length, and other behavioral guidelines. ChatGPT incorporates these instructions into its system prompt for all new conversations initiated by that user.
Practical Use Cases
Custom Instructions are useful for professionals who interact with ChatGPT regularly in consistent contexts. A software developer might specify they want code examples in a particular language with detailed explanations, while a content writer might request responses in a specific tone and structure. Students can indicate their educational level to receive appropriately pitched explanations, and researchers can provide domain-specific context to improve the relevance of responses. The instructions persist across separate conversations, eliminating the need to restate preferences and context repeatedly.
Source Notes
- 2026-04-07: How to Set Up ChatGPT, Claude & Gemini for Legal Work
- 2026-04-22: AI Agent Skills · ▶ source
- 2026-04-28: ChatGPT · ▶ source
- 2026-04-29: Hermes · ▶ source
- 2026-05-01: Modern AI Agentic Harness: Architecture, Components, and Framework Differences · ▶ source