Pro model · Anthropic · updated 2026-09-26

Claude Opus 5.5

Top-tier reasoning, coding, and long-context work. API id: anthropic/claude-opus-5.5

Anthropic's flagship for the hardest work: deep reasoning, big refactors, and long documents.

Best for

Multi-step builds, architecture reviews, debugging tangled code, and analysis over long pasted context. When the free pool feels shallow, this is the deep end.

Use it

Pick it in the Web Agent or Chat picker, or pass anthropic/claude-opus-5.5 to /api/agent.php. Needs Pro or your own key.