Struct DecideEnv 

pub struct DecideEnv<'a> {
    pub calibrated: bool,
    pub plan_label: Option<&'a str>,
    pub tool_descriptions: &'a BTreeMap<String, String>,
}

What the scheduler may ask a decision backend, as FROZEN in the run manifest (docs/decision-model-proposal.md C1/C2). Pure data: the scheduler never calls a backend — it emits a decision EFFECT the driver answers and journals, the same shape every other effect has.

Fields

calibrated: bool

The pinned backend’s calibrated(). The scheduler’s two uses of a decision both OMIT something (tools from an offer, entries from a prompt), and rule 2 of the proposal is that an uncalibrated backend may reorder but never omit — so with false nothing is asked at all.

plan_label: Option<&'a str>

The plan’s human label (name, and its goal/description when it has one) — narrowing context (C1).

tool_descriptions: &'a BTreeMap<String, String>

Pinned tool name → its one-line description — narrowing context (C1). A pure function of the manifest’s pinned Definitions (immutable by hash), so live and verify build the same table.