Problem definition. When generative AI produces expert artifacts clients cannot distinguish from a competent provider's, the classical cost-based quality signal collapses and only outcome-contingent commitments can separate types. Such a commitment certifies an endogenous, perishable asset: the human fallback capability a firm builds by keeping staff engaged with cases the AI handles, eroding otherwise. Prior work is silent on where that mechanism holds. We ask where, across occupations and liability institutions, it remains informative. Methodology/results. We introduce an institutional wedge between the liability cap a firm posts and the retained exposure that carries information, generated by four legal primitives: the cost rule, the enforceability of penalty clauses, the displacement of private liability by state liability or pooled indemnity, and mandatory limits on contractual liability. The wedge compresses the separating type space into a signaling window, bounded above by solvency and the penalty doctrine and below where standard-terms control voids caps beneath a threshold. We calibrate five occupations and seven jurisdictions on published evidence. In common-law agreed-damages channels the provability gross-up is unavailable whenever verifiability falls below 1/m, turning a contracting problem into an operational one. Verifiability investment widens the window where the ceiling binds but narrows it where the cap floor binds. In an agent-based market, within the tested policy class, every empty-window cell converges to zero engagement and skill collapse. Managerial implications. Liability institutions are a workforce-capability instrument, not merely a risk-allocation device. Firms should target the binding margin in each jurisdiction; cap floors and pooled indemnity each suppress the signal sustaining fallback capacity.
Firms that deploy improving but imperfect AI must decide how much to keep human workers engaged. Engagement lowers current output yet builds the fallback skill the firm needs when AI fails. We ask what that fallback skill signals to two audiences at once: mobile workers, who sort across firms on the skill trajectory a job builds, and clients, who cannot observe skill in a credence-good market and must infer competence. We embed the engagement-skill dynamics of Singh et al. (2026) in a signaling game and add a liability commitment. Because a more-skilled provider fails less often precisely in the states where AI is down, the expected cost of a liability pledge is decreasing in fallback skill. This restores Spence-Mirrlees single crossing on a type that is endogenous - built, not drawn - and yields a separating equilibrium in which liability certifies preserved human competence that no artifact can certify once AI writes as well as the expert. We characterize the least-cost separating pledge schedule, show that client stakes shift engagement toward or away from the least-skilled worker depending on the size of the pledge, and derive a stakes threshold above which building skill dominates free-riding on a rival's training - reversing the asymmetric-specialization result of the underlying labor model. Two boundaries close the market from both sides: small tickets cannot fund enforcement, and large tickets exceed the provider's solvency. An agent-based version of the market reproduces the analytical thresholds under noisy beliefs, learning-by-record and worker churn.
It is shown that provenance certification priced as a type-independent stamp (e.g., C2PA) cannot restore full separation, while a verified commitment to forgo the AI frontier re-imposes the pre-AI artifact cost function.