Fundamentals
Context window
The maximum number of tokens a model can consider at once, counting both the input you send and the output it generates. Go over it and the model forgets or refuses.
In practice
A 200K context window fits a few long documents plus the conversation. A 1M window can hold an entire codebase.
Related terms
See what your tokens really cost
Track usage and spend across every model and platform, free.
Image: Google DeepMind on Pexels. Definition free to reuse under CC BY 4.0.