Calibrated Abstention and Escalation in Foundation-Model Systems

This review examines calibrated abstention and escalation in foundation-model systems. The organizing question is when a model should answer, defer, request evidence, or transfer control to a person. Ten related scholarly sources are synthesized through a decision-centered framework spanning problem definition, mechanism, measurement, evaluation, implementation, and governance. The review does not invent experiments, pooled estimates, or unreported quantitative results. It instead evaluates the strength and transferability of the available evidence, with particular attention to treating a fluent refusal style as evidence of calibrated uncertainty. The resulting framework links technical or empirical performance to explicit use conditions and identifies tests that should precede wider adoption in high-consequence decision support with bounded model authority.

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