The CO-STAR Framework — A Universal Prompt Structure That Survives Model Changes

A six-letter universal prompt structure (Context, Objective, Style, Tone, Audience, Response) that works unchanged across ChatGPT GPT-5.4, Claude Opus 4.7, and Gemini 3.1 Ultra — and keeps working when the next model ships. The closest thing to an industry-standard prompt structure for complex generative tasks like client emails, proposals, LinkedIn posts, cold outreach, and fundraising asks.