Research release

Cohere Labs releases Tiny Aya L2-Thinker for in-language reasoning across 60 languages

The 3.35B open-weight research model is trained to keep reasoning in the user’s language, combining English reasoning, translated multilingual reasoning and non-reasoning multilingual data.

Open Model Weights published7 Oct 2026
Primary sourceCohere Labs
Source published2026-10-06

Cohere Labs has released Tiny Aya L2-Thinker, a 3.35B open-weight research model designed to reason in the language of the user’s prompt instead of defaulting to English reasoning traces. The work builds on the Tiny Aya base model with a 32K context length and studies what Cohere calls L2, or in-language, reasoning across 60 languages. The publisher reports that the resulting model produces reasoning in the prompt language more than 93% of the time across its evaluation set while keeping most task accuracy close to an English-reasoning counterpart.

The central contribution is the data mixture rather than a language-specific architecture. Cohere Labs combines about 1.7 million English reasoning examples with multilingual reasoning examples translated into 44 languages and a third pool of multilingual question-and-answer data without reasoning traces. In the publisher’s ablations, the multilingual reasoning slice sharply raises the rate of in-language reasoning, while the non-reasoning multilingual data helps generalization to languages that do not have dedicated reasoning supervision. Cohere also calls out competition-level mathematics as a harder case where the accuracy trade-off is more visible.

Cohere Labs says it is releasing both the model weights and multilingual reasoning data on Hugging Face. For Open Model Weights, this is a model-release candidate as well as a training-method signal: the canonical record should separately verify the exact repository artifacts, license, context and lineage, while the reported multilingual benchmark and reasoning-rate results remain attributed research claims. The release is especially relevant to the evidence layer because the training recipe is described in enough detail to record source-backed methodology without turning benchmark comparisons into a universal quality ranking.

OMW REGISTRY WATCH

What this changes for the evidence layer

Open-weight multilingual reasoning candidate. Verify the exact Hugging Face repository, files, license and configuration before canonical ingestion. The reported in-language reasoning rates and comparisons are Cohere Labs research results and remain attributed.

PRIMARY SOURCE

Cohere Labs

This brief is based on the cited primary source. Performance, benchmark and comparative claims remain attributed unless Open Model Weights publishes an independent measurement.

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