# Claude Opus 4

> The large half of the generation that made Claude a coding model first and everything else second: sustained work measured in hours rather than answers measured in seconds, which is the shape every agent took afterwards. Thirteen months, and then the same funeral as Sonnet 4. Anthropic kept the weights; what closed was the endpoint.

2025-05-22 — 2026-06-15 · lived 1 year

This URL is the guided walk — the 3D cemetery, standing at this grave. The written record is at [Claude Opus 4's epitaph](https://models.rip/claude-opus-4/epitaph).

## Elsewhere

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