be able to distinguish between changes in choice options and outcomes that comply with the *reference independence* property and those that do not. For example, in a consultation scenario, a consulted agent may want to check if the consulting agent is providing a proposal that is *seemingly* barely adding new choice options, but covertly also altering the preferences over existing choice options. Such a scenario is presented in greater detail in Section \[dialoges\].

Abstract Argumentation {#argumentation}
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To allow for a concise overview of the relevant foundations of abstract argumentation, we introduce a formal definition of the basic structure of an argumentation framework (AF), provide the definitions of well-established argumentation semantics, and explain the notion of argumentation expansions and principles.

 [@dung1995acceptability]\[arg-f\] An argumentation framework is a pair $AF := (AR, Attacks)$, where *AR* is a finite set of arguments, and $Attacks$ is a binary relation on *AR*, *i.e.* $Attacks \subseteq AR \times AR$.

In the context of an argumentation framework, *a attacks b* means that\
$attacks(a,b)$ holds. Similarly, *a set $S$ attacks $b$* if $b$ is attacked by an argument in $S$, and *$c$ defends $b$* if $a$ attacks $b$ and $c$ attacks $a$.\
To select coherent sets of arguments 