Managed Agents vs. cron agents: when to use which
Two agent architectures I’ve actually built, one triggered by a user and one running on a schedule. How to tell which one your problem needs before you build the wrong one.
Most people who say “I want an AI agent” actually mean one of two very different things. Picking the wrong one is half the reason agent projects stall, because the architecture decides the plumbing, the cost and the experience. I have built both kinds and shipped them, so here is the practical split.
The cron agent
A cron agent runs on a schedule, with no user waiting for it. My SEO agent is this kind. It wakes up on a daily, weekly and monthly cadence, inspects a site, decides what to fix and reports back on its own. Nobody clicks a button and nobody watches it work.
This shape fits monitoring, audits, and any repetitive task that should simply happen on its own, whether or not anyone is thinking about it. The value is that it never forgets and never gets bored, so problems get caught the week they appear rather than the quarter someone finally looks.
The managed, on-demand agent
The other kind is triggered by a person and streams a result back while they wait. My Prospect Analyzer is this kind. It runs as a Managed Agent on Anthropic’s API. Someone drops in a brand, the agent crawls the site and streams a readiness report as it works. It turned a task that took me over twenty minutes by hand into under three.
This shape fits interactive analysis, where a human wants an answer now and wants to see progress rather than stare at a spinner. The streaming is not a nice-to-have here, it is the product, because watching the work build trust in the result.
How to tell which one you need
| Cron agent | Managed / on-demand | |
|---|---|---|
| Who triggers it | A schedule | A person |
| Latency | Does not matter | Answer now, show progress |
| Best for | Monitoring, audits, upkeep | Interactive analysis on demand |
| Output goes to | A report or a pull request | The screen, streamed live |
| Cost shape | Predictable, on a cadence | Per request, spikes with use |
Why it matters
The two need different plumbing under the hood. A cron agent needs a scheduler, durable runs that survive restarts, and reporting nobody has to watch live. A managed agent needs streaming, a responsive interface and a cost model that can absorb spikes when several people trigger it at once.
Build a cron agent where the problem wanted an on-demand one and it feels sluggish and pointless. Build it the other way around and you are paying for interactivity nobody uses. Neither mistake is about the model, and neither shows up in a demo.
So before anyone writes a line of code, the real question is not “which model” but “who triggers this, and does anyone wait for it”. Get that answer right and the rest of the design follows from it. If you are not sure which one your problem is, that is a good thing to work out together.
Frequently asked questions
Can one agent be both?
Rarely well. A scheduled job and an interactive tool pull the design in opposite directions, so you usually pick one. If you genuinely need both, run two.
Which one is cheaper to run?
The cron agent is more predictable, because it runs on a cadence you control. The on-demand agent costs per request and spikes with use, so its cost tracks how much people actually use it.
I have an idea but I am not sure which it is. Where do I start?
Answer one question first: who triggers this, and does anyone wait for it. That single answer decides the architecture, and the rest of the design follows from it.