From the article:

Today, Fulcrum is releasing Echo, the best writing model at style imitation. Echo beats frontier models at writing tasks ranging from fiction to technical explanations, despite costing less than $5K to train.

You can try it for free: contact us to scale your usage. We plan on open-sourcing the model soon.

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Echo can do any writing task, from literary fiction to casual chatting, in whatever style you choose.

There are no good canonical metrics for writing quality, and making good metrics for writing is difficult. However, we can measure how good models are at style imitation by using standard stylometric attribution techniques. We computed a number of well-known stylometric features¹ and used them to compute a style Elo².

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We train Echo on top of Kimi K3.

We believe our training gains come from elicitation: teaching the model to activate and use its suppressed knowledge of author style. This is why training Echo is so cheap: the amount of training we do is negligible relative to the amount of data the model is pre-trained on.

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In controlled experiments, we found a surprising degree of learning transfer between authors, i.e., training on author B helps with author A. This supports our hypothesis that the training is eliciting the model’s latent imitation ability.