Open Source Tax Engine outperforming gpt sol and Fable 5

Reddit r/ArtificialInteligence Tools

Summary

An open source tax engine achieved 96% on TaxCalcBench, surpassing previous models, and found inconsistencies in the benchmark itself. It provides a deterministic engine for AI models to use in tax research and preparation.

This is an open source tax engine which scored 96% on TaxCalcBench [highest ever recorded score till date] surpassing fable 5 and sol with just sonnet 5 (which was previously scoring an abysmal 6%). The only 2 cases where it missed, it found inconsistencies in the test cases in the benchmark ITSELF which the maintainers confirmed! Essentially it's a deterministic engine AI models can use for research and tax prep to remove a lot of guesswork and calculation mistakes that often happen. Claude Sonnet 5 was able to top the benchmark with this mcp.
Original Article

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