AI Systems Atlas

X-05Context Overflow

/context/context-overflow

The window fills mid-task; without a plan, the harness truncates — usually the oldest, often the most important.

Key insight

Overflow behavior is an architectural decision that most systems make by accident. Decide it before you need it: what gets evicted, what is untouchable.

Failure mode

Oldest-first truncation: the system prompt and the user’s constraints are, by definition, the oldest things in the window.

Further reading
RelatedContext compactionContext budget

Elsewhere in the atlas

Harnesses →Security →Evals →Coding Agents →