ScientistOne applies Chain-of-Evidence to enforce traceability from every claim to its source during literature review, solution discovery and manuscript generation. arXiv:2605.26340 reports 0/337 hallucinated references, 12/12 score verification passes and 14/15 method-code alignment matches, exceeding five baseline systems on five frontier tasks. CoE Audit further shows baselines with hallucinated reference rates up to 21 percent and score verification as low as 42 percent. The framework generalizes to six additional domains including medical imaging and language modeling, attaining state-of-the-art on Parameter Golf and gold medals on MLE-Bench where prior agents fail entirely. arXiv:2203.02155 and arXiv:2305.11738 document similar verifiability gaps in ReAct-style and Auto-GPT pipelines, confirming the pattern of surface-level output without embedded evidence chains. ScientistOne therefore demonstrates replacement of complete knowledge-work pipelines rather than isolated chat interfaces.