Overview
LangREPL is an interactive terminal chat application built with LangChain, LangGraph, Prompt Toolkit and Rich. It enables fast experimentation and debugging of multi-tool, multi-model agents via a REPL or server mode with LangGraph Studio integration.
Key features
- Interactive REPL and server mode (LangGraph Studio support for visual debugging).
- Persistent conversation storage, todo/approval workflows, and subagent support for complex tasks.
- Extensible tool system and multi-provider LLM support for production-like experimentation.
Use cases
- Research agents that gather and synthesize information into structured outputs.
- Developer workflows for validating agent configurations, tools and model behavior.
- Automation pipelines where tasks are decomposed into tool-driven subtasks.
Technical highlights
- Native Python implementation with pip/poetry/uv packaging for easy integration.
- Modular architecture and example-driven configs facilitate extensibility and deployment.
- MIT licensed and community-maintained for reuse and contribution.