How to evaluate AI vendors when every deck looks the same

I’ve sat through enough enterprise AI sales calls now to write the deck from memory. Enterprise-grade security. Your data stays yours. SOC 2 Type II. Integrates with your stack. State-of-the-art models. A logo slide of firms that look suspiciously like yours. Every vendor says all of it, and most of them can even demo it, because the demos are built on the same handful of foundation models everyone else uses.

That’s the actual problem with AI procurement in 2026. It’s not that vendors lie. It’s that the claims have converged, so the claims carry no information. When every deck says the same six things, capability claims can’t differentiate the vendors. Your evaluation process has to do the differentiating instead, and most buyers don’t have one — they have a demo schedule and a feelings-based scoring meeting afterward. After three years shipping production AI at AnswerAI, the AI product company I run, here is the method I actually use.

Gates before scores

The first mistake is scoring everything on one weighted rubric, where a vendor can be weak on data handling but make it up with a slick interface. No. Some questions are pass/fail, and they get asked before any scoring begins.

Gate one: a contractual commitment that your data is not used to train their models. Contractual. Not a verbal assurance from the sales engineer, not a blog post, not “that’s our current policy.” A term in the agreement you sign. If you want to see what a real commitment looks like in writing, Anthropic publishes theirs plainly: what’s used, what isn’t, under which account types, in language a non-lawyer can parse. That’s the bar. A vendor who can’t produce the equivalent for their own product either doesn’t have the commitment or doesn’t understand their own data flows, and both answers end the conversation.

Gate two: SSO, audit logs, and admin controls, working today, not on the roadmap. This sounds like an IT checkbox until you look at the breach data. IBM’s 2025 Cost of a Data Breach report found that 13% of organizations had already reported breaches of AI models or applications, and 97% of those breached lacked proper AI access controls. The pattern is not exotic attacks. It’s tools deployed without the boring controls, and the boring controls are exactly what a young vendor cuts to ship faster.

And a rule that has saved me more than any checklist: if a vendor hedges on a gate question, the evaluation is over. “I’ll have to check with legal on the training clause” is an acceptable answer once. “It depends on the tier” delivered evasively, a redirect to the security page, an offer to set up a call with their CISO in three weeks — those are answers too, and the answer is no. Vendors who clear the gates say so immediately, in writing, because it’s a selling point. The hedge is the data.

Score your workflows, not their demo

Vendors who pass the gates get scored on weighted criteria. Here’s the part most evaluations get backwards: the criteria have to come from your workflows, not from the demo. A demo is a workflow the vendor chose because their product wins at it. Your job is to test the workflows your people are actually paid for.

For the professional-services firms I work with, three criteria carry most of the weight. First, long-document handling, because these firms live in 100-page files: agreements, workpapers, financial statements with stapled exhibits. Plenty of tools that dazzle on a two-paragraph prompt fall apart at page 60, and you will not discover that in a demo built on a two-paragraph prompt. Test with your longest ugly document, not their sample.

Second, integration with the systems where the work actually happens. If your firm runs on a practice-management tool and a document store, an AI tool that lives in a separate browser tab is asking every user to pay a context-switching tax on every use. The tax compounds into non-use.

Third, what I call the precedent-library test: can it draft from your best past work? Most firms’ real moat is twenty years of well-crafted deliverables. A tool that generates generic output from a generic model is replaceable by any other tool doing the same. A tool that drafts your engagement letter from your ten best prior engagement letters is doing something you’d miss. This single test separates vendors faster than anything else I run, and it’s the one no demo ever volunteers.

Weight these against your own volume and pain, put numbers in a matrix, and make the scorers defend their scores against the tests, not their impressions. The sample Vendor & Model Evaluation Brief shows the full scoring matrix for a composite client — more at /examples.

Price last

Price enters the evaluation last, and deliberately. Not because money doesn’t matter at a 50-to-500-person firm, but because an unused tool is expensive at any price, and price pressure is how unused tools get bought.

The competition your sanctioned tool actually faces is not the other vendor in the bake-off. It’s the free personal account your employees already have. Microsoft’s Work Trend Index found that 78% of AI users were bringing their own AI tools to work, and Cyberhaven’s 2026 AI Adoption & Risk report documents where that leads: corporate data flowing into AI tools through personal accounts, outside every control you negotiated in the gates above. If the tool you bought loses the daily head-to-head against a free consumer account — slower, clunkier, worse at the actual work — your people will quietly use the free one, your data will follow them, and you’ll have purchased shelfware plus a shadow-AI problem. The cheap tool nobody uses costs more than the expensive tool everyone uses. Evaluate for the version that wins the head-to-head, then negotiate price on that one.

One platform, narrow exceptions

At 50 to 500 people, I push clients toward one primary AI platform plus a short list of narrow exceptions, and away from best-of-breed sprawl. This is unfashionable advice. The best-of-breed argument sounds sophisticated: the best tool for legal drafting, the best for research, the best for meetings.

But every additional vendor is another governance surface — another training clause to verify, another admin console, another audit log nobody reviews, another security questionnaire at renewal. It’s another training track for staff who are already stretched learning one tool well. And it’s another place your precedent library fragments: the prompts, examples, and refined workflows your team builds up are an asset, and splitting that asset across four tools means owning four shallow ones. A mid-sized firm doesn’t have the operational surplus to govern five AI vendors properly. It barely has enough to govern one. The exceptions should be genuinely narrow: a vendor-reviewed point tool for a specific regulated workflow, not a second general assistant because one partner prefers the other interface.

Evaluation is a cadence, not an event

The last piece is the one nothing in traditional procurement prepares you for: the product you evaluated will not be the product you’re running in six months, even if you never touch a setting. Model providers ship updates on their schedule, not yours, and updates change behavior, not just capability.

I’ve watched a routine model update shift the tone of drafted client letters mid-quarter — same prompts, same workflow, noticeably different voice going out under the firm’s name. Nobody chose that. The fix was procedural, not technical: a house style guide pinning the drafting voice, and a lightweight re-test of the core workflows so a drift like that gets noticed in days instead of surfacing in a client’s raised eyebrow.

So the evaluation you ran before signing becomes a standing artifact, re-run on a cadence. Keep the test set: the long ugly document, the precedent-drafting test, the tone check. Re-run it quarterly and after any announced model change. Put a re-evaluation clause in the contract — notification of material model changes, the right to re-test, and exit terms that don’t trap you for a year with a product that drifted out from under its own demo. The vendors who pass the gates won’t fight this clause. They know their product changes monthly. The ones who fight it are telling you they’d rather you didn’t look, and by now you know what to do with that answer.