Struct TracingHandler 

pub struct TracingHandler { /* private fields */ }

Bridges CallbackHandler events to one or more TraceExporters.

Implementations

impl TracingHandler

pub fn builder() -> TracingHandlerBuilder

Start a new builder.

pub fn record_score(&self, score: ScoreRecord)

Submit an out-of-band evaluation score for an existing run_id.

pub fn stats(&self, exporter_name: &str) -> Option<(usize, usize, usize)>

Stats per exporter (sent, dropped, failed).

pub async fn shutdown(self)

Graceful shutdown: drain batchers, then call each exporter’s shutdown(). Must be awaited.

Trait Implementations

impl CallbackHandler for TracingHandler

fn name(&self) -> &str

Friendly name for diagnostics.

fn on_chain_start(&self, runnable: &str, input: &Value, run_id: Uuid)

A Runnable (chain / graph) started.

fn on_chain_end(&self, _runnable: &str, output: &Value, run_id: Uuid)

A Runnable finished successfully.

fn on_chain_error(&self, _runnable: &str, error: &str, run_id: Uuid)

A Runnable errored.

fn on_tool_start(&self, tool: &str, args: &Value, run_id: Uuid)

Tool execution started.

fn on_tool_end(&self, _tool: &str, result: &Value, run_id: Uuid)

Tool execution finished.

fn on_tool_error(&self, _tool: &str, error: &str, run_id: Uuid)

Tool errored.

fn on_node_start(&self, node: &str, _step: u64, run_id: Uuid)

Graph node started.

fn on_node_end(&self, _node: &str, _step: u64, output: &Value, run_id: Uuid)

Graph node finished.

fn on_checkpoint(&self, _step: u64, _run_id: Uuid)

Graph engine persisted a checkpoint.

fn on_custom(&self, kind: &str, payload: &Value, run_id: Uuid)

Custom node-emitted event.

fn on_llm_start(&self, model: &str, prompt: &Value, run_id: Uuid)

LLM / chat-model invocation started.

fn on_llm_token(&self, _token: &str, _run_id: Uuid)

LLM emitted a streamed token.

fn on_llm_end(&self, model: &str, output: &Value, run_id: Uuid)

LLM finished a generation.

fn on_llm_error(&self, _model: &str, error: &str, run_id: Uuid)

LLM errored.