Reflection AI 发布开源模型 Beam-1.0-501B-A23B，跻身 Agent Arena 榜单前列
Reflection AI 放了个 501B 的全开源模型，Agent Arena 上是美国开源模型里最强的，Code Arena 前二十几个开源模型里唯一的非中国选手，Apache 2.0 随便用。
Reflection AI 的 Beam-1.0-501B-A23B 已上线 Agent Arena，总排名 #13，在 US 实验室中排 #6。该模型以 Apache 2.0 协议完全开源，在开源权重模型中 Agent Arena 排 #12（Net Improvement -3.67%），领先 Hy3、MiMo V2.5 Pro 和 MiniMax M3。在 Code Arena: WebDev 上它以 1438 分排开源模型 #22，是榜单前 25 名开源模型中唯一来自中国实验室之外（美国）的模型，排在 Kimi K2.5 Thinking 和 GLM-5 之前。不过其 Net Improvement 误差范围为 ±3.84%，与榜单上方的两个 Qwen3.8 模型在统计上差距不大。
Beam-1.0-501B-A23B just landed in the Agent Arena. With this release, @Reflection_AI is now in the Agent Arena top 15 labs! Among US labs, Beam-1.0-501B-A23B is #6 , and overall is #13 . Congrats to the team at @Reflection_AI on this contribution to the open-source ecosystem! Arena.ai @arena Exciting news: Beam-1.0-501B-A23B by @Reflection_AI just landed #12 among open weight models in Agent Arena with -3.67% Net Improvement, and #22 among open in Code Arena: WebDev with 1438 pts. It’s also fully open under Apache 2.0. On the Agent Arena leaderboard, Beam 1.0 is the top-ranked US model among open models, landing at #12 . That puts it ahead of Hy3, MiMo V2.5 Pro and MiniMax M3. Its margin of error is wide (±3.84% on Net Improvement), so it’s statistically closer to the two Qwen3.8 models just above it than its rank suggests. On Code Arena: WebDev, 24 of the top 25 open models come from Chinese labs. The one exception is Reflection’s Beam 1.0 (Apache 2.0). It ranks #22 among open models, which makes it the top US open model on the board, just ahead of Kimi K2.5 Thinking and GLM-5. Congrats to the @Reflection_AI team on this solid open weights release! 🔗 View Quoted Tweet 💬 7 🔄 1 ❤️ 27 👀 3635 📊 7 ⚡
