Struct TreeMeta 

struct TreeMeta {
    description: String,
    control_only: bool,
    call_signatures: HashSet<String>,
    steps: Vec<TreeStep>,
}

Metadata for one in-flight RTDL tree in the forest. Trees are keyed by pilot-assigned plan_id; this carries what the supervisor and the LLM need to reason about a running tree (and, later, what the chat UI renders).

Fields

description: String

LLM-supplied rtdl_description (sub-task label).

control_only: bool

True when this tree is purely control ops (only cancel_plan / cancel_all_plans). Such trees are NOT advertised to the LLM as cancellable in-flight work — a cancel is not itself a task tree, and listing it makes the model cancel its own cancels in a loop.

call_signatures: HashSet<String>

Canonical provider/contract/args signatures for calls in this tree. The harness rejects a second tree containing an identical call while the first is still in flight; execution latency must not duplicate a physical or external command.

steps: Vec<TreeStep>

Ordered executable leaves from the original RTDL graph. Keeping these visible lets the model target any semantic boundary in one control call instead of querying live state first or guessing what “current” means.