OpenAI introduces GPT-5.3-Codex-Spark, a smaller, ultra-fast version of Codex built for coding in real time. Can you imagine seeing changes in your code almost instantly while you edit in VS Code or the terminal? That’s exactly what Codex-Spark aims for: an interactive experience where latency matters as much as intelligence.
What is Codex-Spark
Codex-Spark is a model optimized for fast inference and interactive work. It’s a smaller variant of GPT-5.3-Codex designed for near-instant responses, able to generate more than 1000 tokens per second and with a context window of 128k tokens. For now it’s text-only, focused on directed editing, logic refinement, and quick changes in interfaces.
Who is it useful for? For developers who iterate in the moment: quick tests, guided refactoring, and real-time collaboration with an assistant that responds without long pauses.
Why it matters now
AI isn’t just for long background tasks anymore. What if you could interrupt, redirect, and iterate with the model in the same session, without waiting? Codex-Spark opens that path, combining two modes: long-term high-level work and instant collaboration for when you need results right now.
