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GLM-5.3

Z.ai · #1 in our ranking · Best overall

GLM-5.3 is an open-weight mixture-of-experts model from Z.ai, released Aug 2026, with 753B parameters, a 1M-token context window, and the GLM-5.3 License.

GLM-5.3 keeps the GLM-5.2 base model and puts every gain into post-training. Z.ai reports open-source state of the art on Terminal Bench 3.0 and Agents' Last Exam, and a 50% gain over GLM-5.2 on its in-house code benchmark.

GLM-5.3 specs

Context1M tokens
Parameters753B
Provider
Z.ai
Architecture
Mixture-of-experts
Parameters
753B total
Context
1M tokens | 786K words
License
GLM-5.3 License
Input
Text
Released
Aug 2026

Sourced from the model card on Hugging Face. Last checked 2026-10-01.

Highlights

  • 1M-token context
  • Top open-weight scores on agentic benchmarks
  • Built for long, multi-step tool use

Where it fits for payment teams

  • Payment reconciliation

    #2 pick. Top open-weight agentic scores, so it reliably chains ledger queries, processor APIs, and file parsing across a long run.

  • Chargebacks and disputes

    #3 pick. Strong at long, multi-tool runs that pull from the processor, shipping data, and the help desk.

  • Merchant underwriting

    #1 pick. The strongest open-weight model for long agentic runs that chain KYB, sanctions, and internal data.

  • AML and compliance investigations

    #2 pick. Reliable over long investigations that touch many data sources.

Harnesses in Runtime

Run GLM-5.3 through any of these harnesses on Runtime.

Claude CodeOpenCodeCline

Provider-reported benchmarks

Terminal Bench 2.188.2
Toolathlon Verified73.0
CyberGym84.5

Benchmark scores are reported by each model provider on its Hugging Face model card. They are not independently verified by Runtime.

How to run GLM-5.3

01

Download the weights

Pull zai-org/GLM-5.3 from Hugging Face. Check the GLM-5.3 License before you deploy.

02

Serve it in your cloud

Run it with vLLM or SGLang on your own GPUs, or use a managed provider that hosts the model.

03

Put it to work in Runtime

Point an agent or a single skill at the model through OpenCode, then compare it to your current model with evals.

GLM-5.3 FAQ

What is the context window of GLM-5.3?

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GLM-5.3 supports a 1M-token context window (1,048,576 tokens), roughly 786K words of English text.

How many parameters does GLM-5.3 have?

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GLM-5.3 is a mixture-of-experts model with 753B total parameters.

Is GLM-5.3 free for commercial use?

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GLM-5.3 is released under the GLM-5.3 License, a custom license. Commercial use may come with conditions, so read the license on Hugging Face before you deploy or fine-tune it.

What can GLM-5.3 take as input?

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GLM-5.3 accepts text input and generates text.

Is GLM-5.3 good for payment reconciliation?

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Yes. GLM-5.3 is our #2 pick for payment reconciliation. Top open-weight agentic scores, so it reliably chains ledger queries, processor APIs, and file parsing across a long run.

Is GLM-5.3 good for chargebacks and disputes?

+

Yes. GLM-5.3 is our #3 pick for chargebacks and disputes. Strong at long, multi-tool runs that pull from the processor, shipping data, and the help desk.

Is GLM-5.3 good for merchant underwriting?

+

Yes. GLM-5.3 is our #1 pick for merchant underwriting. The strongest open-weight model for long agentic runs that chain KYB, sanctions, and internal data.

Is GLM-5.3 good for AML and compliance investigations?

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Yes. GLM-5.3 is our #2 pick for AML and compliance investigations. Reliable over long investigations that touch many data sources.

Can I run GLM-5.3 in my own cloud with Runtime?

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Yes. Download the weights from Hugging Face (zai-org/GLM-5.3) and serve them with vLLM or SGLang in your cloud, or use a managed provider that hosts the model. Runtime agents can then use GLM-5.3 through a harness like OpenCode, with your data staying in your environment.