Qwen3.8 27B
A compact, deployment-friendly dense model: a native vision-language model that understands images and videos, with flexible thinking control, designed to carry complex, multi-step tasks through to completion with greater reliability.
Qwen’s own description of the model, from
Qwen3.8-27B model card . Served here as qwen/qwen3.8-27b.
What Qwen built it for
in the vendor’s words- “Comprehensive improvements across coding, professional work, research, and long-horizon agentic tasks.”
- “Stronger autonomous planning and better handling of environment feedback, leading to more reliable end-to-end task completion.”
- “Native support for image and video understanding, from STEM diagrams and documents to hour-scale videos.”
Quoted from Qwen3.8-27B model card, retrieved 23 Aug 2026. Thinking on by default, with a reasoning-depth dial. The card does not label its benchmark tables thinking or non-thinking, so no row here claims a mode the vendor did not state.
Published benchmarks
Qwen’s figures, not ours| Benchmark | What it measures | Score | How Qwen ran it |
|---|---|---|---|
| Terminal Bench 2.1 Terminus harness | Agentic terminal coding | 73.0 | The card names the Terminus harness for this row and states no further sampling detail. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| SWE-bench Pro | Agentic coding, real-world software engineering | 61.7 | Claude Code harness, temperature=1.0, top_p=0.95, 256K context window; "Problematic tasks were corrected, and all baseline models were re-evaluated on the refined benchmark". Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| LiveCodeBench v6 | Competitive coding | 90.3 | The card states no separate harness or sampling for this row. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| Agents' Last Exam | Frontier agentic tasks | 20.4 pass@1 / 42.9 score | The card reports this row as two figures, pass@1 and score. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| GPQA Diamond | Graduate-level science reasoning | 89.2 | The card states no separate harness or sampling for this row. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| HLE | Humanity's Last Exam, multidisciplinary reasoning | 30.8 | Judged by GPT-4o. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| MathVision | Visual maths problem solving | 90.0 without code interpreter / 94.6 with | Evaluated with the fixed prompt "Please reason step by step, and put your final answer within \boxed{}"; a small number of incorrect ground-truth annotations were corrected before scoring. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
| OSWorld-Verified | Computer use, from screenshots | 84.3 | The card states no separate harness or sampling for this row. Mode: not stated for this row; the card states the model operates in thinking mode by default. |
Every score above is Qwen’s own published result for this model, copied from Qwen3.8-27B model card on 23 Aug 2026 — we did not run these benchmarks and we do not restate them as our own. Each vendor ran its own harness with its own judge, so these tables are not a league table: scores from two different cards are not comparable, even where the benchmark name matches. Each model here shows only its own maker’s table, for that reason.
Recommended usage
what Qwen recommendsSampling
For thinking mode, Qwen recommends temperature=1.0, top_p=0.95, top_k=20, min_p=0.0, presence_penalty=0.0, repetition_penalty=1.0. That is what this
endpoint sends when your request omits them, so the default request shape
is the vendor’s recommendation rather than ours. An explicit value in
your request always wins.
Qwen publishes a second set for instruct (non-thinking) mode:
temperature=0.7, top_p=0.80, top_k=20, min_p=0.0, presence_penalty=1.5, repetition_penalty=1.0.
This endpoint carries one set of sampling defaults per model, not one per thinking mode, so a request that turns thinking off still gets the thinking arm's values unless it sets its own. If you turn thinking off, send these six parameters yourself to match Qwen's recommendation for that mode.
On repetition, Qwen notes: “you can adjust the presence_penalty parameter between 0 and 2 to reduce endless repetition. However, using a higher value may occasionally result in language mixing and a slight decrease in model performance.”
Thinking
Thinking is on by default and its depth is a dial: reasoning_effort takes xhigh (the vendor default, "for complex tasks demanding thorough analysis"), medium ("balancing accuracy and speed") and low ("efficient reasoning optimizing for speed and cost").
Qwen’s own caution: “In multi-turn agentic tasks, lower reasoning effort does not always reduce overall task completion time. Although it may produce faster per-turn responses, it can also lead to insufficient analysis, more failures, and repeated retries, which may increase total latency and token consumption.”
On this endpoint: Reasoning depth is a dial: reasoning_effort accepts low, medium, and xhigh (the vendor default), and "none" turns reasoning off entirely for latency-critical turns.
Context length
Qwen gives the native window as 262,144 tokens, which is what we serve — the full checkpoint window, with input and output sharing it. Beyond the native window the vendor points at YaRN RoPE scaling, to a ceiling of 1,000,000 tokens, and warns against leaving it on for ordinary traffic.
Qwen’s caution on extending it: “All the notable open-source frameworks implement static YaRN, which means the scaling factor remains constant regardless of input length, potentially impacting performance on shorter texts.” We serve the native window and do not enable static RoPE scaling, so ordinary-length requests are not paying that cost.
What to point it at
Qwen names these workloads for this model:
- “coding, professional work, research, and long-horizon agentic tasks”
- “from STEM diagrams and documents to hour-scale videos”
Output length
“To optimize performance on agentic tasks, we recommend allocating sufficient output length to allow the model to generate detailed and comprehensive responses.” For agentic work the vendor asks for room to think: a 262,144-token cap on reasoning content and a 131,072-token cap on the final response.
Output here is not capped below the context window, so there is room to follow that advice.
Recommendations on this page are Qwen’s, from Qwen3.8-27B model card, retrieved 23 Aug 2026. We default to them rather than to a house preference; where our default would differ, this page says so.
What it does on this endpoint
our measurements · not vendor figures
These three are ours, measured on the live endpoint — observations, not service
guarantees, and not to be confused with the vendor scores above. The protocol,
the vantages, the build each figure is pinned to and how to check it against the
system_fingerprint in your own response are all on
the measurements page. Run your own and use
those instead.
Price
per million tokens · no request fee · no subscription| Input | Cached input | Output |
|---|---|---|
| $0.40 | $0.10 | $2.03 |
One price, no tiers. Cache hits are applied automatically and reported per
response as cached_tokens. Full price sheet
and worked examples.
Capabilities
qwen/qwen3.8-27bThree API formats, one base URL
OpenAI Chat Completions, OpenAI Responses, and Anthropic Messages — all
served from https://api.tiyuvta.ai/v1. Point an existing client at
it and set the model id; there is no product-specific SDK.
Tools and structured output
tools and tool_choice, JSON mode, and JSON
schema via response_format. The tool-call round trip is
part of the release gate on every deploy.
Vision and video
Images go in as image_url content parts and bill as ordinary
input tokens — vision costs nothing extra.
Video goes in as video_url content parts; sampled frames bill as input tokens.
Reasoning: an effort dial
Reasoning depth is a dial: reasoning_effort accepts low, medium, and xhigh (the vendor default), and "none" turns reasoning off entirely for latency-critical turns.
Prompt caching
Continuing a conversation reuses its prefix and bills the cached rate for what actually hit — reported per response, priced per token, no hit-rate promises.
Exactness-gated serving
Speculative decoding is verified byte-identical to plain decode on the serving configuration before a build takes traffic — speed never changes the output. The correctness gates.
Where it fits best
use it for- Work where the reasoning-effort dial earns its cost — hard analysis, long plans, tricky code
- Products serving EU users: it serves from Germany as well as the US, routed by geography
- Video input — the only model here that accepts video
- A second opinion next to Ornith-1.5, on the same key and the same balance
For most workloads, start with the flagship: Ornith-1.5 35B-A3B — faster and cheaper, on the same key.
First request
qwen/qwen3.8-27bcurl https://api.tiyuvta.ai/v1/chat/completions \
-H "Authorization: Bearer $TIYUVTA_KEY" \
-H "Content-Type: application/json" \
-d '{"model": "qwen/qwen3.8-27b",
"messages": [{"role": "user", "content": "Hello"}]}' The default request reasons before it answers, at Qwen’s recommended sampling — best quality for hard problems.
curl https://api.tiyuvta.ai/v1/chat/completions \
-H "Authorization: Bearer $TIYUVTA_KEY" \
-H "Content-Type: application/json" \
-d '{"model": "qwen/qwen3.8-27b",
"reasoning_effort": "none",
"messages": [{"role": "user", "content": "Hello"}]}' reasoning_effort: "none" makes the first streamed
token the answer itself — the measured 185 ms first-token
figure above is this request shape.
- Weights and vendor sources
- huggingface.co/Qwen/Qwen3.8-27B, Apache-2.0. Qwen trained this model; we serve it at its full native context in NVFP4 4-bit weights. Benchmark scores and usage recommendations on this page come from Qwen3.8-27B model card , retrieved 23 Aug 2026.
- Machine-readable metadata
-
GET https://api.tiyuvta.ai/v1/modelsfor supported parameters, and the provider feed atGET https://api.tiyuvta.ai/models?schema=openrouter. - Rate limits
- Per account, for abuse control, raised on request — capacity scales with demand rather than sitting behind a published ceiling.