Callback and tracing system

This module provides callbacks for observability, tracing, and monitoring.

Quick Start

use lc_callbacks::{CallbackManager, StdOutHandler, LangSmithHandler};
use std::sync::Arc;

// Create callback manager with handlers
let manager = CallbackManager::new()
    .add_handler(Arc::new(StdOutHandler::new()))
    .add_handler(Arc::new(LangSmithHandler::from_env()?));

// Use with LLM or Agent
let llm = OpenAIChat::new(config);
// llm.with_callbacks(Arc::new(manager));

Environment Variables for LangSmith

• LANGSMITH_API_KEY: API key (required, starts with "ls_")
• LANGSMITH_TRACING: Enable tracing (default: "true")
• LANGSMITH_PROJECT: Project name (default: "default")
• LANGSMITH_ENDPOINT: API endpoint (default: LangSmith official)
• LANGSMITH_WORKSPACE_ID: Workspace ID (required for org accounts)