The right owner of an AI evaluation depends on what happens when the output is wrong. A shared model team can provide expertise and consistent methods. The product team still has to explain the consequence in the workflow it owns.
Two uses of the same model can require different acceptance decisions. An internal drafting aid may leave every sentence open to review. A workflow that updates a record can turn a plausible answer into an external effect. Treating both as one model-quality problem removes the distinction that matters to the user.
Start at the point of use
For an illustrative support product, imagine a model that retrieves policy text and proposes a response. A support specialist reads the draft before sending it. The relevant evaluation is partly about the retrieved material and partly about the review process. A technically accurate draft can still be unfit if it leaves out the condition that determines whether the policy applies.
The support owner knows which conditions change the customer outcome. The central team may know how to construct consistent test runs, compare versions, and diagnose changes in model behavior. Neither view is sufficient alone.
NIST's MEASURE 2.3 calls for performance or assurance measures under conditions similar to deployment and recommends evaluating with people responsible for user interaction and experience. This supports bringing the review interface and use context into the assessment. It does not prescribe product-team ownership or establish that a particular reporting line produces better outcomes. The ownership division below is an application of that guidance to the support scenario.
A practical division starts with the product owner defining the decision the user needs to make. Domain specialists identify errors that could change it. The shared evaluation team helps turn those distinctions into reproducible tests. The release authority decides whether the remaining failures fit the permitted use.
This is a design proposal, not a claim that one organizational arrangement always performs better.
Share methods without flattening consequences
Common tooling can make results comparable and reduce repeated work. A common test format, version record, and route for inspecting failures can help teams challenge each other's evidence. These benefits do not depend on imposing one acceptance threshold on every product.
In the support example, a response that misstates an eligibility condition may require a hold even if most of its language is correct. In a separate internal search tool, a partial answer with clearly linked sources might still be useful. The difference comes from how the result will be used and checked.
The central team should be able to reject an unsound measurement method. The local owner should be able to reject a test set that misses a consequential domain condition. Disagreement should produce a sharper evaluation or an explicit limit on use, rather than a negotiation over whose dashboard is authoritative.
Keep the unresolved case visible. If no one can determine whether a certain error matters, the system may need a narrower permitted use until that question is answered.
Resolve the disputed case before the aggregate
Suppose the support owner classifies an omitted condition as a consequential failure while the central evaluator treats it as a minor completeness issue. Averaging the disagreement into a score would hide the question that needs a decision.
Construct a paired example. Keep the customer request and proposed answer the same, but change the condition that determines which policy applies. Have the domain owner explain the different next action in each case. The evaluator can then assess whether the expected distinction is observable and whether the test actually measures it.
If the difference cannot be established from the available material, retain an unresolved case. The product may need to ask for more context or prevent the response from being used without domain review. Uncertainty about the expected answer is itself relevant to the permitted behavior.
This exercise also clarifies the handoff when a product changes owners. The receiving team inherits the reason for the case, the current acceptance decision, and the condition that would require reevaluation. It should not inherit an unexplained score whose threshold was negotiated in a meeting no one can reconstruct.
Make that transfer part of the product's operating documentation. Shared tooling can preserve the mechanics, but continuity of judgment requires preserving the consequence and its owner. This is especially useful when the central team supports several products with similar interfaces and materially different definitions of a harmful error.
Avoid assigning the entire burden locally
Local ownership has limits. A product team may not be equipped to assess shared infrastructure failures or risks that affect other products. Letting every team invent its own method can also make results difficult to inspect. Common controls and independent expertise have value precisely because a local release creates incentives and blind spots.
The useful boundary is therefore specific. Central ownership can cover evaluation infrastructure, common failure categories, and minimum evidence quality. Product ownership covers the meaning of a successful user outcome and the behavior that is acceptable in that context. Some decisions require both.
For a new AI feature, write a short description of the user action that follows the model output. Name who understands that action and who can change it. Bring those people into the evaluation before the metric becomes a release target. A method designed around a benchmark is easy to run repeatedly. A method designed around the product consequence is easier to use when the result forces a difficult choice.