ChatGPT logo, a keyboard, and a robotic hand in this illustration taken June 5, 2026. REUTERS/Dado Ruvic/Illustration Purchase Licensing Rights, opens new tabSept 16 (Reuters) - OpenAI said on Wednesday it has introduced AI-powered tools for advertisers and begun testing business-sponsored agents for users to chat with, stepping ​up its push into the increasingly ‌competitive market for AI-driven marketing.Here are more details: Sign up here.The Sponsored Agents feature will let users start con...