Long-Running Agent

Simple Definition

A Long-Running Agent is an AI agent designed to keep working toward a goal over an extended period, minutes, hours, or longer, while preserving its progress and state along the way, rather than completing a single short task and stopping.

What Long-Running Agents Require

Persistent state, so progress survives interruptions instead of resetting
Checkpoints, saved points the agent can resume from
Budget limits, caps on time, cost, or steps so the agent doesn’t run indefinitely
Progress logs, a record of what’s been done and what’s left
Retries, a defined way to recover from a failed step without losing everything before it
Stop conditions, clear rules for when the agent is actually done or should give up
Resumable sessions, the ability to pause and pick back up later
Durable files, work saved somewhere that outlives any single execution
Human escalation, a path to hand off when the agent gets stuck
Verification, checking that long stretches of unsupervised work are actually correct, not just completed

Why It Matters

A short task that goes wrong wastes a few minutes. A long-running agent that goes wrong without checkpoints, budgets, or verification can waste hours of compute, drift far off course before anyone notices, or take a large number of small wrong actions that compound into a serious problem. The infrastructure listed above exists specifically to catch that early instead of after the fact.

Example

A long-running agent tasked with migrating a large codebase might checkpoint its progress after each module, log what it changed and why, stop and ask for review if test failures exceed a threshold, and resume from the last checkpoint rather than starting over if the session is interrupted.

Task Budget, the limit that keeps a long-running agent from running away
Agent Sandbox, the boundary a long session should still respect throughout
Human-in-the-Loop, the escalation path when the agent gets stuck
Agent Swarm, multiple long-running agents working in parallel
AI Loop, the repeating structure that keeps a long-running agent moving
Verification Gate, the check that should apply throughout, not only at the end
Persistent Agent State, the specific information that gets checkpointed and resumed
Event-Driven Agent, an agent that idles between triggers rather than running continuously