@levie: At Box, we’ve been testing Fable 5.1 in early release against our complex enterprise work eval. Fable 5.1 delivers a hu…
Summary
Box tested Fable 5.1, which delivered a 7 percentage point improvement over Fable 5 in complex enterprise tasks, with notable gains in financial services, technology, and public sector, and it will be available in Box AI Studio alongside new models Claude Fable 5.1 and Claude Mythos 5.1.
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At Box, we’ve been testing Fable 5.1 in early release against our complex enterprise work eval. Fable 5.1 delivers a huge 7 percentage point jump over Fable 5 for unstructured data tasks in the enterprise.
On this updated test, we use the Box Agent with Fable 5.1 to work through a wide range of real world enterprise scenarios with documents in financial services, life sciences, the public sector, and more industries. All of these tasks require a high degree of analytical, math, logic, and domain knowledge to perform successfully.
Here are a few examples of wins:
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Financial Services (+17% improvement): on a tax-adjusted profit projection, Fable 5.1 correctly applies capital allowances before computing tax liability; this is a subtle ordering that Fable 5 misses, producing wrong figures all the way through retained earnings.
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Technology (+37% improvement): on a cost-optimization analysis where a key metric’s normalization is ambiguous, Fable 5.1 recognized the ambiguity, computed both forms, and presented the correct one, where Fable 5 committed to the wrong normalization.
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Public Sector (+16% improvement): on an educational data analysis task, Fable 5.1 works through the full weighted-mean methodology and produces correct rankings, while Fable 5 miscategorizes one item and cascades errors through the whole sheet.
These are just a few of the wins we saw. Overall major jump in capability for long running agentic workflows in the enterprise.
Fable 5.1 will be available shortly in the Box AI Studio for building custom AI agents with enterprise content.
Claude (@claudeai): We’re introducing Claude Fable 5.1 and Claude Mythos 5.1.
They’re the world’s most advanced models for coding and knowledge work.
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