OpenAI describes how ChatGPT's ad stack works

OpenAI published a post, summarized by @OpenAIDevs on X on October 21, on how ChatGPT's advertising system is built. OpenAI says it is designed to respond to the evolving conversation while keeping answers independent of ads.

As OpenAI describes it:

• An LLM orchestrator turns a conversation into multiple intents by exploring the user's possible needs.
• Embedding-based search finds candidate ads, then eligibility and relevance checks narrow the pool.
• An auction tool handles the final selection and pricing.
• The ChatGPT frontend shows eligible ads below the answer, labeled as sponsored.
• If an ad arrives after the answer is fully generated, it is not shown for that turn. OpenAI says the answer does not wait for ads.