RL environment with FHIR R4 state and dual-layer safety rubric exposes that frontier models fail multi-step workflows (Claude 1.0%, GPT-5.4 0.0%) despite partial single-step competence.
May 22, 2026
Summary
Static QA benchmarks miss failure modes that matter in production medical workflows—trajectory-level safety collapse and tool misuse under sustained pressure. Developers deploying clinical LLMs now have a measurement harness that catches what reaches real patients, not abstract accuracy.
Why it matters
Static QA benchmarks miss failure modes that matter in production medical workflows—trajectory-level safety collapse and tool misuse under sustained pressure. Developers deploying clinical LLMs now have a measurement harness that catches what reaches real patients, not abstract accuracy.
Implementation verdict
Replaces toy medical QA evals with realistic multi-step task chains (195 tasks, 2,255 binary criteria, 515 safety-critical). Requires FHIR R4 integration, MCP tool support (24 exposed), and deterministic LLM-judge overlay for evaluator noise control. Ready to pilot now—code, tasks, Docker bundle released under Apache 2.0—but training-reward signal is not production-safe yet per authors' own 0.929 prevalence gameability finding. Use for benchmarking before deployment; training ablations pending.
Sources
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