Trait ContextOverflowRecovery 

pub trait ContextOverflowRecovery: Send + Sync {
    // Required method
    fn recover<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        messages: Vec<AgentMessage>,
        cx: &'life1 TransformContext<'life2>,
    ) -> Pin<Box<dyn Future<Output = Vec<AgentMessage>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait;

    // Provided methods
    fn max_attempts(&self) -> u8 { ... }
    fn name(&self) -> &'static str { ... }
}

Recovers from a provider context-window rejection MID-RUN.

The token-estimate heuristics that drive ContextTransform are approximate, so a request can still exceed the model’s real window and come back as crate::StreamError::ContextOverflow. When one is installed, the loop hands this hook the current history, the impl returns a smaller one (typically an aggressive compaction), and the loop retries the SAME LLM call — bounded by max_attempts, and with the shrunk history persisted into the live transcript so later turns don’t immediately re-expand.

Distinct from ContextTransform on purpose: this fires ONLY on an overflow (never on every round), its result is written back to the caller’s transcript (not just the request clone), and returning an unshrunk history ends recovery rather than spinning.

Required Methods

fn recover<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, messages: Vec<AgentMessage>, cx: &'life1 TransformContext<'life2>, ) -> Pin<Box<dyn Future<Output = Vec<AgentMessage>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Produce a smaller history for the retried request. cx carries the same observables as a ContextTransform (cancellation signal, model id, iteration, last provider usage, estimator). Returning a history no shorter than the input signals “cannot shrink further” and the loop stops retrying.

Provided Methods

fn max_attempts(&self) -> u8

Maximum recovery attempts within a single run. Default 1.

fn name(&self) -> &'static str

Label for the AgentEvent::ContextTransformApplied diff event emitted after a successful shrink, so observers can attribute the history change.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors