OpenRouter users are loving Anthropic's Opus 5.5
It is the #1 model in share of spending across the platform and has led a rebound for Anthropic in the competition with OpenAI
Sonnet 5.5 and Haiku 5.5 have also seen strong launch periods
Spend share on a multi-model router is a revealed-preference signal for which models practitioners actually pay for, useful when picking a default model for AI agentAn AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.Full definition → workloads.
Terms in this piece · Glossary
AI agent — An AI system that doesn't just answer once but works toward a goal in a loop — taking actions, reading the results, and deciding what to do next.
