Nathaniel Whittemore

Is it benchmark maxed?

Yes, 100%.

But so is every other model.

Is it frontier leader in any single category?

No.

Is it better than I expected?

Yes.

I look forward to the eventual open source version.

Feels like they're coming back to life.

Never fade Zuck.

Now, speaking of open source, another model that we got this week that got completely overshadowed by the Mythos announcement was z.ai's GLM 5.1.

And at least on the benchmarks, it's the first open source model to overtake leading Western models on coding benchmarks.

The new Frontier model, which like I said is called GLM 5.1, achieved a 58.4 on SweeBench Pro, beating GPT 5.4 and Opus 4.6, who scored 57.7 and 57.3 respectively.

Z.ai also provided a mixed benchmark that included Terminal Bench 2.0 and NL2 repo as well, which had GLM 5.1 slightly behind the two US leaders but ahead of Gemini 3.1 Pro.

Still, if those benchmarks hold, it puts GLM 5.1 in the top echelon of frontier models with a clear separation from QEN 3.6 Plus and KimiKey 2.5.

And indeed, what most people are clinging onto is the fact that this is a full open source release with commercial licensing.

It's a gigantic 754 billion parameter model, so you're not going to be running it locally on a Mac Mini.

Still, it gives developers the opportunity to build on top of current generation state-of-the-art models for kind of the first time.

We've been tracking the apparent shift in Chinese lab strategy away from open source recently, but this release suggests that leading Chinese labs are at least still somewhat willing to give away their best performing models.

In terms of performance, ZAI provided a few impressive examples in agents and coding.