Framework Level Tracing For Langchain And Llamaindex With Chain Agent Visibility

via “callback and event system for observability and monitoring”

Framework for building LLM applications with chains, agents, retrieval, and tool use.

Unique: Implements a callback system that emits events at each execution step (LLM calls, tool invocations, chain steps) with support for both sync and async handlers. Integrates with LangSmith for cloud observability and supports custom callback implementations for external monitoring systems.

vs others: More comprehensive than simple logging and more flexible than rigid monitoring frameworks because callbacks are composable and can be registered globally or per-component without modifying application code.