GLM-5.1: Towards Long-Horizon Tasks
Highlights
- ▸GLM-5.1 is a 754B MIT-licensed open model — the scale at which open weights can exist without commercial restrictions keeps climbing
- ▸Z.ai is positioning explicitly around long-horizon agentic tasks — a bet that the next differentiating capability isn't raw reasoning, it's multi-step stamina
- ▸Available via OpenRouter means any developer can try it without downloading 1.51TB — the distribution channel is as important as the license
Original excerpt
Sponsored by: Honeycomb — AI agents behave unpredictably. Get the context you need to debug what actually happened. Read the blog
GLM-5.1: Towards Long-Horizon Tasks. Chinese AI lab Z.ai's latest model is a giant 754B parameter 1.51TB (on Hugging Face) MIT-licensed monster - the same size as their previous GLM-5 release, and sharing the same paper.
`` llm install llm-openrouter llm -m openrouter/z-ai/glm-5.1 'Generate an SVG of a pelican on a bicycle' ``
And something new happened... unprompted, the model decided to give me an HTML page that included both the SVG and a separate set of CSS animations!
I usually don't do follow-up prompts for the pelican test, but in this case I made an exception:
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