Qwen3.8-Flash: Million-Token Intelligence, Built for Agentic Work
RouterHub Team · Updated 2026-08-27

Qwen3.8-Flash is now available on RouterHub as qwen/qwen3.8-flash. The model combines a 1-million-token context window, text, image, and video input, up to 128K output tokens, and built-in tool support. Its published evaluation profile is strongest across coding, agentic workflows, professional knowledge work, and general reasoning.
Qwen3.8-Flash at a Glance
| Item | Published specification |
|---|---|
| Provider | Qwen, Alibaba Group |
| RouterHub model ID | qwen/qwen3.8-flash |
| Input | Text, image, and video |
| Output | Text |
| Context window | 1 million tokens |
| Maximum output | 128K tokens |
| Published base architecture | 125B-parameter main model, plus 51B N-gram embedding parameters |
| Activated parameters | 6B per token |
| Production features | Built-in tools and API compatibility for OpenAI- and Anthropic-style integrations |
Qwen describes Qwen3.8-Flash as the production version built on Qwen3.8-Flash-Next. The production model extends the underlying release with a 1-million-token context window by default and official built-in tools.
Published Coding and Agentic Results
Qwen’s published evaluations for Qwen3.8-Flash-Next, the model underlying Qwen3.8-Flash, show a broad performance profile across repository-level engineering, tool use, and long-horizon tasks.
| Benchmark | Published result | What it evaluates |
|---|---|---|
| DeepSWE 1.1 | 58.7 | Agentic software engineering |
| SWE-bench Pro | 62.5 | Difficult repository-level software engineering |
| SWE-bench Multilingual | 81.0 | Multilingual software engineering |
| NL2Repo-Bench | 48.1 | Repository-level code generation |
| CoWorkBench | 73.9 | Long-horizon office and professional work |
| JobBench | 55.7 | Professional job tasks |
| Toolathlon Verified | 73.5 | Real-world tool use |
The results point to a model designed for more than short code completion. Qwen3.8-Flash is positioned for tasks that require reading a large working set, acting through tools, and sustaining progress across multiple steps.
Published Reasoning and Instruction-Following Results
| Benchmark | Published result | What it evaluates |
|---|---|---|
| IFBench | 81.3 | Instruction following |
| GPQA Diamond | 91.7 | Graduate-level scientific reasoning |
| HLE | 35.9 | Difficult multidisciplinary reasoning |
| LiveCodeBench v6 | 91.9 | Competitive coding |
These benchmarks use different task sets, scales, and evaluation harnesses. The results were published by Qwen and have not been independently reproduced by RouterHub.
Long-Context Efficiency
Qwen3.8-Flash-Next uses a hybrid Gated DeltaNet and Qwen Sparse Attention design. At a 1-million-token context length, Qwen reports that the sparse-attention kernel reached up to 7.6× faster prefill and 4.9× faster decode in its experiments. In an online-serving setup with a 90% prefix-cache hit rate, Qwen also reports 8.6× the prefill throughput of Qwen3.7-Plus.

Those figures matter most for applications that work with large repositories, long documents, extended conversations, or repeated shared context. They indicate that the model’s long-context capability is paired with an architecture designed to retrieve relevant information without applying full attention to every token at every layer.
Where the Performance Profile Stands Out
Qwen3.8-Flash is a strong candidate for evaluation when a workload combines several of the following requirements:
- repository-scale coding and debugging;
- long-horizon agentic execution;
- tool use across multi-step workflows;
- professional document and office tasks;
- multimodal analysis across text, images, or video;
- long-context reasoning with large working sets.
The published results provide a useful starting point, but production evaluation should still use representative prompts, tools, context sizes, and success criteria from the intended application.