Struct TelemetryMiddleware 

pub struct TelemetryMiddleware { /* private fields */ }

Auto-registered middleware that calls telemetry functions. Zero-overhead when tracing-support and metrics features are disabled (all telemetry functions compile to no-ops).

Automatically prepended to every LlmAgent’s middleware chain at build time, so all agents get observability by default.

Implementations

impl TelemetryMiddleware

pub fn new(agent_name: impl Into<String>) -> Self

Create a new telemetry middleware for the given agent.

pub fn agent_name(&self) -> &str

Returns the agent name this middleware is tracking.

Trait Implementations

impl Middleware for TelemetryMiddleware

fn name(&self) -> &str

Unique name for this middleware (used in logging/debugging).

fn before_agent<'life0, 'life1, 'async_trait>( &'life0 self, _ctx: &'life1 InvocationContext, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called before an agent begins execution.

fn after_agent<'life0, 'life1, 'async_trait>( &'life0 self, _ctx: &'life1 InvocationContext, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called after an agent completes execution.

fn before_tool<'life0, 'life1, 'async_trait>( &'life0 self, call: &'life1 FunctionCall, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called before a tool is invoked.

fn after_tool<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, call: &'life1 FunctionCall, _result: &'life2 Value, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called after a tool completes successfully.

fn on_tool_error<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, call: &'life1 FunctionCall, _err: &'life2 ToolError, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called when a tool execution fails.

fn on_error<'life0, 'life1, 'async_trait>( &'life0 self, err: &'life1 AgentError, ) -> Pin<Box<dyn Future<Output = Result<(), AgentError>> + Send + 'async_trait>>

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

Called when an agent error occurs.

fn before_model<'life0, 'life1, 'async_trait>( &'life0 self, _request: &'life1 LlmRequest, ) -> Pin<Box<dyn Future<Output = Result<Option<LlmResponse>, AgentError>> + Send + 'async_trait>>

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

Called before an LLM model call is made. Return Some(LlmResponse) to skip the LLM call and use the returned response instead (e.g., for caching, guardrails). Return None to proceed.

fn after_model<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _request: &'life1 LlmRequest, _response: &'life2 LlmResponse, ) -> Pin<Box<dyn Future<Output = Result<Option<LlmResponse>, AgentError>> + Send + 'async_trait>>

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

Called after an LLM model call completes. Return Some(LlmResponse) to replace the model’s response (e.g., for output filtering, safety). Return None to use the original response.

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

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

Called when an agent event is emitted.