long-context

A capability-by-capability tour of frontier LLMs in 2026 — which models are strong at reasoning, code, math, long-context, multilingual, multimodal, and tool use, with hedged comparisons instead of point-estimate benchmark wars.

What the context window actually is, why 1M-token marketing doesn't mean what you think, the cost and accuracy curves that bend as you stuff more in, and the strategies (compaction, caching, retrieval) that keep long-context apps sane.