OpenAI has recently published a detailed architecture description of the Codex App Server, a bidirectional protocol that decouples the Codex coding agent's core logic from its various client surfaces.

OpenAI has launched GPT-5.3 Codex offering a 25% speed increase over GPT-5.2 Codex, helping developers ship code faster.

Brian Beers is a digital editor, writer, Emmy-nominated producer, and content expert with 15+ years of experience writing about corporate finance & accounting, fundamental analysis, and investing.

Think of a REST API like a waiter in a restaurant. You (an app) tell the waiter what you want (your request), and the waiter goes to the kitchen (the server) to get it for you. REST is just a set of ...