Enum StopCause 

pub enum StopCause {
    Completed,
    MaxTurns,
    OutputTokenBudget,
    CostBudget,
    Interrupted,
    Loop,
    NoOutput,
}

Why the loop stopped. Completed is the model deciding it was done; everything else is the harness cutting it short.

Variants

Completed

MaxTurns

OutputTokenBudget

CostBudget

Interrupted

Someone cancelled it — a user pressing Ctrl-C, a shutdown, a timeout.

Loop

The model repeated an identical tool call, with an identical result, right after a compaction — the sign that compaction did not carry the task and the run is stuck re-living it. Distinct from MaxTurns on purpose: “hit the turn limit” reads as the task being too big, when a stuck run is a different problem with a different fix.

NoOutput

The model returned turns with no content at all — no text, no tool calls — and did not recover when asked to answer. A thinking model does this when the whole per-turn budget goes to reasoning and the answer never starts; the provider reports max_tokens, or even stop, with an empty message.

Distinct from Completed for the reason Loop is distinct from MaxTurns: this used to report success. A run that produced nothing returned StopCause::Completed with exhausted: false, so it was indistinguishable from a model that finished and had nothing to say — which is how it went unnoticed until it accounted for 15 of 28 Terminal-Bench trials, every one of them scored as an ordinary failure.

Implementations

impl StopCause

pub fn is_early(self) -> bool

True when the harness cut the run short, so the answer may be partial.

pub fn describe(self) -> &'static str

Trait Implementations

impl Clone for StopCause

fn clone(&self) -> StopCause

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for StopCause

impl Debug for StopCause

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for StopCause

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for StopCause

impl PartialEq for StopCause

fn eq(&self, other: &StopCause) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for StopCause

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for StopCause