Definition
A24: “Let C be a family of pragmatic contexts, and let e_C denote the distribution of communicative judgments observed in context C. A translation τ induces a correspondence between contexts”. Fidelity is D(τ) = Σ_C w_C d(e_C^source, e_τ(C)^target): whether “the translation preserves the pattern of context-dependent communicative judgments, rather than … one canonical vector of meaning”. It is “a candidate objective function, not an established translation metric”.
What it is not
Not the whole of fidelity in the manuscript, where it is L_obs, one of three terms (§6). It does not say how the context correspondence is found; A24: “the correspondence between contexts cannot be assumed”. The dynamical requirement of TERM-007 is added to it, not substituted for it.