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AgentHooks

agent_sdk

Trait AgentHooks 

Source 
pub trait AgentHooks: Send + Sync {
    // Provided methods
    fn pre_tool_use<'life0, 'life1, 'async_trait>(
        &'life0 self,
        invocation: &'life1 ToolInvocation,
    ) -> Pin<Box<dyn Future<Output = ToolDecision> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
    fn post_tool_use<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        _tool_name: &'life1 str,
        _result: &'life2 ToolResult,
    ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait { ... }
    fn on_event<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _event: &'life1 AgentEvent,
    ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
    fn on_error<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _error: &'life1 Error,
    ) -> Pin<Box<dyn Future<Output = bool> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
    fn on_context_compact<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _messages: &'life1 [Message],
    ) -> Pin<Box<dyn Future<Output = Option<String>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
    fn pre_llm_request<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _request: &'life1 ChatRequest,
    ) -> Pin<Box<dyn Future<Output = RequestDecision> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
    fn on_llm_response<'life0, 'life1, 'async_trait>(
        &'life0 self,
        _response: &'life1 ChatResponse,
    ) -> Pin<Box<dyn Future<Output = ResponseDecision> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }
}
Expand description

Lifecycle hooks for the agent loop. Implement this trait to customize agent behavior.

Provided Methods§

Source

fn pre_tool_use<'life0, 'life1, 'async_trait>( &'life0 self, invocation: &'life1 ToolInvocation, ) -> Pin<Box<dyn Future<Output = ToolDecision> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Called before a tool is executed.

Receives a structured ToolInvocation that bundles tool identity, tier, requested input, effective input, and listen-context — everything a server-side policy engine needs for an allow / block / confirm decision.

Return ToolDecision::Allow to proceed, ToolDecision::Block to reject, or ToolDecision::RequiresConfirmation to yield for user approval.

Source

fn post_tool_use<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _tool_name: &'life1 str, _result: &'life2 ToolResult, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Called after a tool completes execution.

Source

fn on_event<'life0, 'life1, 'async_trait>( &'life0 self, _event: &'life1 AgentEvent, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Called when the agent emits an event. Can be used for logging, metrics, or custom handling.

Source

fn on_error<'life0, 'life1, 'async_trait>( &'life0 self, _error: &'life1 Error, ) -> Pin<Box<dyn Future<Output = bool> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Called when an error occurs. Return true to attempt recovery, false to abort.

Source

fn on_context_compact<'life0, 'life1, 'async_trait>( &'life0 self, _messages: &'life1 [Message], ) -> Pin<Box<dyn Future<Output = Option<String>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Called when context is about to be compacted due to length. Return a summary to use, or None to use default summarization.

Source

fn pre_llm_request<'life0, 'life1, 'async_trait>( &'life0 self, _request: &'life1 ChatRequest, ) -> Pin<Box<dyn Future<Output = RequestDecision> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Input guardrail: called with the outbound llm::ChatRequest before it is sent to the provider.

Return RequestDecision::Proceed to send it unchanged, RequestDecision::Modify to substitute a sanitized request, or RequestDecision::Block to refuse the call (e.g. prompt-injection or PII policy). The default proceeds unchanged.

Source

fn on_llm_response<'life0, 'life1, 'async_trait>( &'life0 self, _response: &'life1 ChatResponse, ) -> Pin<Box<dyn Future<Output = ResponseDecision> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Output guardrail: called with the provider’s llm::ChatResponse before it is persisted or surfaced.

Return ResponseDecision::Accept to keep it, ResponseDecision::Block to reject it, or ResponseDecision::RetryWithFeedback to reject it and steer a retry (e.g. output moderation or secret-leakage detection). The default accepts.

Dyn Compatibility§

This trait is dyn compatible.

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

Implementors§