# Claude 2.1

> It doubled the window to two hundred thousand tokens, and within a fortnight someone had hidden a single sentence in the middle of one and published what came back. Anthropic replied with a post showing that adding one line — "Here is the most relevant sentence in the context:" — moved recall from 27% to 98%. The headline was the window; the durable lesson was about how you ask.

2023-11-21 — 2025-07-21 · lived 1 year, 7 months

This URL is the guided walk — the 3D cemetery, standing at this grave. The written record is at [Claude 2.1's epitaph](https://models.rip/claude-2.1/epitaph).

## Elsewhere

- [The whole cemetery](https://models.rip/)
- [The dataset](https://models.rip/graveyard.json)