AI & models
Context window
How much the model can hold in mind at once — your question, the files it's looking at, and everything said so far — measured in
tokens. Think of it as the model's desk space. When it fills up, the oldest things start to slide off the edge. Why it matters
Part of Context and the context window → If a long Claude session starts forgetting earlier details, you've probably filled the context window. /clear or /compact gives it a clean desk.