Function retrieve_grounding 

pub fn retrieve_grounding(
    directory: &str,
    task: &str,
    scope: Option<&str>,
    top_k: i64,
    budget: i64,
    live_only: bool,
) -> Value

retrieve_grounding(directory, task, scope, top_k, budget, live_only) — the contract-shaped payload, pre-serialization (budget::serialize caps it).