PaperTrail

▎ PaperTrail is a provenance-grade verification platform for clinical-evidence claims. Given a claim like "lecanemab caused brain swelling in 21.3% of patients," it retrieves the primary source (PubMed / ClinicalTrials.gov), extracts the actual finding, recomputes the effect size deterministically, and flags exactly where the claim diverges — with a trust score and a citation trail where every flagged span maps to a verbatim substring of the cached source. ▎ ▎ The core design decision: deterministic math decides every verdict; Claude only writes grounded language and routing hints — it is never in the numeric or scoring path. The grounding guarantee is enforced as a code invariant (an audit ran 500k+ adversarial fuzz iterations and could not produce an unsourced span). ▎ ▎ Three named-user tools sit on top: Verify a claim, a Lab Notebook that turns dictated bench notes into a grounded, reproducible experiment record (nothing it can't quote is kept), and a Trial Matcher that assesses a de-identified patient against ClinicalTrials.gov criterion-by-criterion. A Mixture-of-Agents pipeline composes 20+ engines (MiniCheck, cross-source aggregation, PyMARE pooling, a discrepancy auditor, STORM debate) into one deterministic verdict. ▎ ▎ What I found (honest): on a single-source clinical benchmark the deterministic + audit path beats a plain Claude call 95% vs 90%; on contested multi-source claims it ties at 100% but stays 87% accurate when the API is down (Claude-alone: 0%). I then audited the entire statistical core (~18 modules — meta-analysis, GRADE, survival, network-meta, fragility, pharmacovigilance) against the biostatistics literature and fixed real correctness bugs: a confidence-interval false-positive on the verify path, a 2× trial-sequential error, a fragility-index bug that inverted "fragile" and "robust," and negation-parity bugs that flipped support↔refute. ▎ ▎ Why it matters: a translational researcher or medical-affairs reviewer must produce and defend numbers. A hallucinating LLM can't be trusted for that. PaperTrail's verdicts are deterministic and every claim traces back to its primary source — provenance, not opinion.