AI 101

Context window

Sketch: a windshield shows instructions, a file and chat while other notes sit out of view; then input and output share one bar.

The context window is how much text, counted in tokens, a model can look at in one go, including your prompt and its answer.

Think of it like this: The context window is the windshield: everything the engine can see right now. What falls outside the frame is out of view unless the harness puts it back.

Source:

https://developers.openai.com/api/docs/concepts (checked Oct 15, 2026)
https://platform.claude.com/docs/en/build-with-claude/context-windows (checked Oct 15, 2026)

RelatedToken Memory PromptContext engineering

Used inContext engineering Financial research and earnings summary agent