Definition. Finite feedback world [ftip-008C]
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    For the action and feedback sets of Definition [ftip-007Q], a finite feedback world \(w\) supplies, for each round \(0\leq n<N\), a probability kernel \(K_{n,w}\) from a generic action--feedback history \((a_0,f_0,\ldots ,a_n)\) ending in \(a_n\in \mathcal A_n\) to \(\mathcal F_n\). Thus, whenever \(a_j\in \mathcal A_j\) and \(f_j\in \mathcal F_j\),

    \[ K_{n,w}(\,\cdot \mid a_0,f_0,\ldots ,a_n) \in \Delta (\mathcal F_n). \]

    Two worlds may agree on every feedback kernel queried by a protocol while differing in latent utility, unrequested labels, or unobserved environment facts. Those latent fields are not feedback until a declared query exposes them.