claude-opus-5-fast

Anthropic · Claude Opus

Anthropic's flagship frontier model. The strongest in the Claude family for complex reasoning, long-context analysis, and nuanced writing. Opus models sit at the top of most benchmark leaderboards but command premium pricing.

pros

• best-in-class reasoning and instruction following
• excellent at long-context tasks (100K+ tokens)
• strong creative and analytical writing
• high safety and refusal calibration

cons

• most expensive tier per token
• can be overly cautious on edge-case prompts
• slower than smaller models

use this model on surp.ivc.lol

Reference this model in a custom combo to always get the cheapest price for it:

curl -X POST https://surp.ivc.lol/api/combos/custom \
  -H "Content-Type: application/json" \
  -d '{"name":"my combo","models":["claude-opus-5-fast"]}'

Or compare it against alternatives: compare claude-opus-5-fast »