How to choose an AI brain tool: seven questions to demonstrate

A useful evaluation turns each buying criterion into something a vendor can show. Keep documented capabilities, observed behavior and unresolved requirements separate.

Bring a small test case, not a sensitive archive

Create two harmless documents for the evaluation: an ordinary project brief and a restricted test note containing the artificial phrase “cobalt orchard.” Give one test user access to both and another access only to the brief. Do not use actual confidential information to discover whether a boundary works.

This fixture will not prove the whole system secure. It gives you a repeatable way to compare the claimed access design with one observed result. Pair it with a representative task, such as asking for the current project milestone and its source.

1. Where is the access decision enforced?

Ask which identity the system uses, which source rules it applies and where it excludes material the requester may not receive. Check both the retrieved evidence and the visible answer where authorized diagnostics permit it.

Filtering only the final prose does not demonstrate that restricted text stayed out of model context. Other controls can still be useful as additional safeguards; the question is which boundary each control actually protects. Source permissions also need attention: a system may faithfully expose a document that was overshared at its origin. Microsoft discusses that issue in its Copilot readiness guidance.

2. Can you inspect the evidence behind the answer?

Follow the citation and compare the passage with the claim. A plausible link is insufficient if the linked text does not support the answer. If the link fails, investigate whether it is stale, malformed or inaccessible; do not declare a disclosure solely because a click failed.

For the project milestone question, require the current milestone and a passage establishing it. A response using an old date fails the task even if its citation opens successfully.

3. What does the audit record actually cover?

Ask which events are recorded, what identifiers connect them, who can read or modify the records and how long they remain. Distinguish administrative configuration events from retrieval events and external actions.

Inspect the record for the harmless test request. Does it show the tested identity and the expected outcome? A tamper-evident record can support integrity checks on captured events; it cannot establish that every relevant event was captured or that every access decision was correct.

4. How do source changes reach the answer?

Change a harmless fact in the project brief and repeat the query. Then change access to the test note and repeat under the appropriate identity. Record the observed behavior and timing separately from the vendor’s documented propagation target.

Do not assume a universal seconds-based deadline. Different connectors can use different indexing and synchronization paths. An observation for one source and configuration is not a service-level commitment for every integration.

5. Where are copies stored and processed?

Ask separately about source documents, indexes, prompts, saved conversations, logs and backups. Identify where inference happens as well as where storage sits. “Self-hosted” or “regional storage” does not answer every question about the complete data flow.

Get the relevant deployment description for the proposed configuration. A marketing page for a different hosting option is not evidence for the one being sold.

6. What changes when you choose another model?

Ask whether the product supports the model/provider combination you need, which features depend on it and how usage is billed. If customer-supplied keys are supported, examine the applicable provider terms and the intermediary’s behavior.

Bringing a key is not itself a guarantee about training, retention or every downstream service. Treat those as separate contractual and technical questions.

7. What is the total cost of the required setup?

Include licenses, model usage, storage, infrastructure, support and the plan needed for administration. Published pricing can make a shortlist easier, while a quote may be necessary for a particular configuration. Neither sales format proves product quality.

For named candidates, see the company AI-tool shortlist. Keep exact current offers in the procurement record rather than relying on old prices in an article.

Make the decision from the evidence gaps

A useful fictional evaluation conclusion is: “The milestone answer and citation passed. The restricted canary was withheld from the narrower test user. Revocation timing and retrieval-event coverage remain unverified; resolve those before expanding scope.” It records progress without claiming the system can never leak.

Use the same distinction for every criterion: documented, observed in this test, or unresolved. That makes a buying discussion much more concrete than seven green feature checkboxes.

About this article

Written by the HeyBrain Editorial Team with AI assistance. The examples are fictional and illustrate design choices; they are not customer stories, product demonstrations or measured test results. Primary sources are linked beside the claims they support.