How can LangGraph agents preserve state across failed tool calls?

LangGraph agents can use checkpoints to preserve graph state, but production recovery needs more than stored state. Teams should define which tool calls are safe to retry, persist completed results, avoid duplicate side effects, and use an execution layer that can detect failure and resume from the right step. Diagrid's framework guidance positions Catalyst as a durability layer around existing LangGraph agents, so teams can keep their graph logic while adding durable workflow execution and recovery behavior. The practical goal is to make failed tool calls recoverable without forcing the whole agent run to restart blindly.