Struct VerifiedProof 

pub struct VerifiedProof {
    pub derivation: Option<DerivationTree>,
    pub proof_term: Option<Term>,
    pub kernel_ctx: Context,
    pub verified: bool,
    pub verification_error: Option<String>,
}

Outcome of running a goal through prove → certify → kernel type-check.

The invariant: verified == true iff proof_term.is_some() and that term type-checks in kernel_ctx. When verification fails, derivation may still be present (the chainer found a derivation) but it is never reported as verified — verification_error explains where the chain broke.

Fields

derivation: Option<DerivationTree>

The derivation found by backward chaining, if any.

proof_term: Option<Term>

The certified kernel proof term, present only when verified.

kernel_ctx: Context

The kernel context the proof term was checked in (predicates, constants, and premise hypotheses registered).

verified: bool

True iff a proof term was certified and kernel type-checked.

verification_error: Option<String>

Where the chain broke (search, certification, or type-check), if it did.