What is the difference between checkpointing and durable execution?

Checkpointing records the state of a run at a specific point. Durable execution is the larger operating model that uses persisted state, workflow history, recovery semantics, and orchestration rules to continue work after failure. A checkpoint might tell you where an agent was; durable execution helps the system decide how to resume safely. In AI agent workflows, that distinction matters because retries can repeat tool calls, LLM output can differ across runs, and external side effects may already have happened. Diagrid's framing treats checkpointing as useful, while Catalyst addresses the broader durable execution layer.