An AI assistant responds when you ask and leaves the decision with you. An AI agent gets a goal and carries out the steps by itself, using your systems. Choose an assistant when the work needs a person's judgement throughout. Choose an agent when the work repeats and the actions can be limited.
How do they compare?
The difference is who moves the work forward. IBM's comparison describes assistants as reactive: they need prompts and suggest actions for you to approve. Agents can keep working after one starting prompt and decide on tools and actions themselves.
| AI assistant | AI agent | |
|---|---|---|
| Starts when | You ask | A goal or an event arrives |
| Next step decided by | You | The agent, within limits |
| Typical output | Text, a summary, a suggestion | A finished action in a system |
| Access to your systems | Often read-only or none | Read and write, as permitted |
| When it's wrong | You notice before using it | You need logs and checks to notice |
What's a quick way to tell them apart?
Look at what happens when you close your laptop. If the work stops, you have an assistant. If it continues and something has changed in your CRM by morning, you have an agent. It's a simple test, and it cuts through most of the labels in product marketing.
When is an assistant the better choice?
When a person is doing thinking work and wants help with it. Drafting a proposal, summarising a long document, preparing for a meeting. The person stays in charge, and each result gets checked because it's being used straight away. It's also the cheaper place to learn. For many teams this is the right first step with AI, and no project is needed.
When is an agent the better choice?
When the same work keeps coming in and the person's main contribution is moving information between screens. Sorting requests, updating records, preparing a reply from three systems. The warning sign that you've outgrown an assistant: your team keeps copying its output into another tool by hand.
What changes when you move from one to the other?
The risk moves. With an assistant, a person reviews every result by nature. With an agent you have to build that review in. So you need things an assistant never asked for:
- Permissions per system and per action
- A log of what it did and why
- Approval moments for actions that matter
- Someone responsible when it fails
- Monitoring after launch
That's why an agent costs more than a subscription, and why it should replace work you've actually measured. Read more on human in the loop and on what agents cost. Our Business Agent includes controlled actions and approval moments for this reason.
Is the line always that clear?
No. Assistants are gaining tools and agents can be set to ask before every step. It's better to see it as a scale than as two boxes. Our guide on agentic AI vs AI agents sets out the levels. When you buy, don't ask what it's called. Ask what it can do without asking you.
