How to Evaluate an AI Agent: 8-Question Checklist (2026) | Viktor Blog
Key Takeaways
- Most AI agent demos lie by omission. They show the happy path with one perfectly worded prompt. The honest evaluation is what happens when the prompt is messy, the data is bad, or the action fails halfway.
- The eight questions below are the ones that separate real products from chat wrappers. If a vendor cannot answer them clearly, walk away.
- Security and audit matter more than features. A tool you cannot trust with your CRM is not actually a tool you can use, no matter how good its outputs look.
- Pricing models tell you what the vendor optimizes for. Per-seat pricing rewards inactive seats. Per-action pricing rewards your usage.
- The right answer for your team depends on what you do most. Writing-heavy teams need different things than ops teams or growth teams.
Why this checklist exists
Last year I sat through 11 AI agent demos in seven weeks. Every one of them went well. Every one of them looked like the answer. Three of them I bought. Two of them ended up shelfware within 90 days.
The pattern: I was asking the wrong questions in the demos. I was watching the output and thinking it was the product. The output is the easy part.
What separated the two products that worked from the three that did not was infrastructure I could not see during the demo: how they handled security, what happened when an action failed, how they integrated with our existing tools, what the audit log looked like, and what they did when they were wrong.
The buyer-side data backs this up. Stanford's 2024 AI Index reported a 32 percent year-over-year jump in publicly reported AI incidents, and Gartner's 2024 forecast projected that at least 30 percent of generative AI projects will be abandoned after proof of concept by end of 2025. Both lines point to the same thing: the demo is not the product, and most evaluations under-weight what happens after the demo ends.
This checklist is what I run through now before I sign any AI agent contract.
Question 1: Does it execute, or does it just draft?
The first thing to figure out is what category you are evaluating.
Some "AI agents" are essentially chat surfaces with better prompts. They write the email, they outline the report, they draft the campaign. You still have to go execute it.
Others are full execution agents. They draft, you approve, they execute. The difference is whether the work actually leaves the chat window and shows up in your CRM, your ad platform, your repo.
Ask in the demo: "Show me an action that touches a real third-party tool and changes its state." If the demo cannot do this, it is a writing assistant, not an agent.
This is not a disqualifier. Writing assistants are useful. But know what you are buying.
Question 2: How does it handle authentication to my tools?
Every AI agent that touches your stack needs credentials. The question is how it stores them and what it can do with them.
Acceptable answers:
- OAuth where the tool supports it (HubSpot, Slack, Google, GitHub, Notion all support this)
- Encrypted API keys with scoped permissions (most other tools)
- A clear scoped-down permission set per integration (read-only where possible, write only where needed)
Unacceptable answers:
- "We use the same credentials as our admin user."
- "You give us your password."
- Vague answers about encryption without specifics on key management.
Ask: "What happens if I disconnect a single integration? Does the rest still work?" The answer should be yes.
Question 3: Does it review before it acts?
This is the single most important behavioral question.
A good agent shows you what it will do before it does it. You see the draft email, the proposed campaign change, the new GitHub branch, before any of those things go live. You approve, edit, or reject.
A bad agent fires actions and then asks for forgiveness. This sounds aggressive in the demo. It is a nightmare in production.
Ask: "Show me what a customer reply looks like before it goes out." The answer should be a draft you can approve. If the answer is "it just sends," walk away unless you only plan to use it for low-stakes notifications.
Question 4: What does the audit log actually show?
Every action an agent takes should be logged. Not just "agent ran" but specifically:
- What action was taken
- Which integration was touched
- What the input was
- What the output was
- Who approved it (if approval was required)
- Timestamp
Without this, you cannot answer the question "did the agent do that or did a person do that?" When something breaks, you need to know. When compliance asks, you need to show.
Ask in the demo: "Show me the audit log for the last 10 actions." If the answer is fuzzy, the audit infrastructure does not exist yet, and you should not put it near anything important.
Question 5: How many integrations does it actually have, and how deep are they?
Vendors love big integration numbers. The numbers are often misleading.
The right way to evaluate: pick the three tools you actually need to connect, and ask the vendor to do a specific workflow in each one. The cleanest way is to write the prompt as you would in production.
If the vendor cannot run a request that touches three tools and creates one new artifact, the integrations are likely surface-level: read-only data exports, not real action surfaces.
Question 6: How does pricing work, and what is the worst case?
Pricing models tell you what the vendor optimizes for.
Per-seat pricing. You pay per user, regardless of usage. Predictable. Tends to lead to "wait, are we using this?" conversations after 6 months.
Per-action or credit-based pricing. You pay for what gets used. The vendor wins when you use it more, which is theoretically aligned with your interest if the agent is creating real value.
Hybrid. Some flat fee plus usage. Common for enterprise.
For each model, ask: "What is the worst-case bill if my team really leans into this?" If the vendor cannot give you a confident answer, that is a signal to be cautious.
Question 7: How does it fail, and how does it tell me when it failed?
Every agent fails sometimes. The model is wrong. The integration is down. The data is unexpected. The right question is what happens then.
Acceptable failure modes:
- The agent surfaces the failure in the channel where the work was requested
- It does not retry destructive actions silently
- It logs the failure with enough detail that a human can debug
- It pings the human who approved the action, not just into the void
Unacceptable failure modes:
- Silent failure, where you only find out a week later when something downstream breaks
- Auto-retry on destructive actions
- Generic "something went wrong" messages with no detail
Ask in the demo: "What happens if the integration times out halfway through this action?" Watch how concrete the answer is.
Question 8: Where does it live in our team's day?
This is the cultural question. It is the one that determines whether your team will actually use it.
If the agent lives in a separate web app you have to remember to open, adoption will be poor. People will use it for the first week and then forget.
If the agent lives in Slack or Microsoft Teams (where conversations are already happening), it gets used. People @mention it the way they would @mention a colleague.
What good answers look like, summarized
| Question | Good answer | Walk-away signal |
|---|---|---|
| Does it execute? | Demos a real action against a real tool | Only shows drafts in chat |
| Authentication? | OAuth, scoped, per-integration | Password sharing, vague encryption claims |
| Review-first? | Draft → approve → execute | Fires actions silently |
| Audit log? | Detailed log of every action | "We have logs" with no specifics |
| Integration depth? | Demonstrates granular write actions | Read-only or surface-level |
| Pricing? | Clear worst-case math | Cannot give a worst-case |
| Failure handling? | Surfaces failures, no silent retries | Generic error messages |
| Surface? | Lives where work happens | Yet another tab |
What about ROI calculations?
Run your own. Pick five workflows your team actually does every week. For each one, write down the average time it takes today and the average time it would take if the agent did the work and a human reviewed it. Multiply by frequency and your blended hourly cost.
If the answer is more than 5x the agent's price, it is probably worth piloting. If the answer is less, you are paying for the wrong workflows.
Frequently Asked Questions
Should I run a pilot before signing an annual contract?
Yes. A 30-day pilot with one team and three workflows tells you more than three vendor demos. Most credible vendors will offer one.
How do I know if the agent is actually saving us time?
Track time-to-completion on the workflows you piloted. Compare before and after. The honest answer is sometimes "it is the same, but the work is more consistent." That is still worth something, but it is a different sale.
Do I need a technical person on the evaluation?
For the security, integration, and audit questions, yes. For the workflow and ROI questions, the operator who feels the pain should drive.
What if my team uses Microsoft Teams and not Slack?
The same questions apply. Make sure the vendor supports your surface natively.