What is the difference between custom instructions and project instructions?
Custom (or global) instructions apply to all your AI conversations — your general preferences. Project instructions apply only within a specific project or workspace, giving focused context for one body of work.
Custom / global instructions
Standing preferences that shape every conversation — tone, role, defaults. Set them once; they apply broadly.
Project instructions
Context scoped to a single project: the background, goals, and constraints for that specific work, kept separate from everything else.
Using both well
Global instructions carry your general style; project instructions carry the specifics. Together they reduce how much you re-explain each time.
Knowing where instructions apply prevents both repetition and the wrong context bleeding into unrelated work.
Global instructions are like your standing preferences with an assistant; project instructions are the brief for one specific assignment.
- Putting project-specific detail in global settings can pollute unrelated chats.
- Sensitive project data in global instructions is a privacy risk.
- Stale instructions can quietly misdirect output.
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Last reviewed 2026-06-25. This topic can change over time; always confirm current specifics from primary sources.