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Model-Agnostic Architecture Is a Scalability Decision, Not Just a Flexibility One

September 2026 · 7 min read

Written by Husain Amjherwala

Model-agnostic AI: workflow layer, interchangeable model slot and governance layer

When we talk about being tied to a single LLM provider, the conversation usually starts with vendor risk. That makes sense, but I think it misses the bigger issue: being too dependent on one model can also make AI harder to scale.

As AI moves deeper into clinical research workflows, the model underneath an application starts affecting much more than the quality of its answers. It can affect cost, speed, capacity, availability, and how much work is involved when something changes.

And something will change. Pricing changes. Models improve. Older models get retired. New capabilities appear. (Anyone who has worked with enterprise technology for long enough has seen this before.)

So the question for clinical innovation and technology leaders isn't simply whether we can switch models. It's how much of the application we would actually have to change if we needed to.

That's really what model-agnostic architecture is about.

Cost

Pricing shifts change the economics of every high-volume task.

Capacity

Throughput and rate limits shape what the workflow can absorb.

Availability

Models get retired, deprecated or repositioned without your input.

Change cost

How much of the application has to be rewritten when any of it moves.

Think of the model as part of the system, not the system itself

One approach we often see is to connect an application to several AI providers and assume that creates flexibility. Technically, it helps. In practice, an application can still become heavily dependent on one provider because of how prompts are written, how outputs are structured, how tools are used, or how the model behaves.

Think about changing the engine in a car. It's one thing if the engine is a component designed to be replaced. It's another if the transmission, electronics, dashboard, and controls have all been designed specifically around that engine.

AI systems can end up in the same position.

The goal is to separate the business workflow from the particular model doing the work. A clinical research application, for example, might need to review a monitoring report and identify potential follow-up actions. That's the job. Whether one model or another performs it should ideally be a technology decision underneath the workflow.

We've found it useful to think about this in simple terms: the application should define what it needs, what an acceptable answer looks like, and what the AI is allowed to do. The model performs the task within those boundaries.

That last part matters. An AI system might search documents, retrieve study information, or suggest creating a task. But the model shouldn't have unlimited control simply because it can request an action. (There is a big difference between suggesting what should happen and holding the keys.)

The application defines the job, the boundaries and what a good answer looks like. The model is what happens to be performing it today.

Being able to switch models doesn't mean they're interchangeable

This is where the idea gets more interesting.

Different AI models don't behave in exactly the same way. A set of instructions that works beautifully with one model may produce a different result with another. Models can vary in how they interpret instructions, handle long documents, use tools, and produce consistent outputs.

So simply connecting to another model isn't enough. We also need to know whether that model can actually do the job.

Evaluate against the real workflow

  • Representative documents from the real workflow
  • Unusual and edge-case records
  • Ambiguous or incomplete information
  • Known failure scenarios
  • Examples where a good result is already defined

I think this changes the question in a useful way. Instead of asking, “Which AI model is best?” we can ask, “Is this model good enough for this particular job?”

That's closer to how we make decisions elsewhere in a business. We don't assign the most senior, expensive expert to every routine task simply because they're capable of doing it. A straightforward, high-volume task may work well with a smaller or less expensive model. A complicated task may need something more capable.

(Headline AI benchmarks are interesting. Your actual workflow is what matters.)

Once an organization understands which models work for which jobs, model choice becomes something it can actively manage rather than a technology decision made once at the beginning of an AI initiative.

There is an important catch

In clinical research, flexibility still needs governance

Changing an AI model isn't only a question of performance and cost, particularly when AI is being used in sensitive or regulated clinical workflows. Suppose we've evaluated another model and it performs the task just as well. Can we simply switch?

Not necessarily.

We still need to understand how data will be processed, what may be logged or retained, whether the model is appropriate for the intended use, whether existing controls remain suitable, and whether anything needs to be reassessed or revalidated. (Being technically able to make a change and being ready to make that change are two very different things.)

Data handling

How data is processed, logged and retained by the new model.

Intended use

Whether the model is appropriate for this specific clinical use.

Controls

Whether existing controls remain suitable, or need reassessment.

Evidence

What supports the decision, and what limitations are known.

This is why I don't think model flexibility and AI governance should be treated as separate conversations. Organizations need to know which models have been reviewed for which uses, what evidence supports those decisions, what limitations are known, and what controls need to remain in place.

That doesn't mean building an enormous governance process around every experiment. The level of control should reflect the use case and its risk. But as AI moves into real operational workflows, the organization needs a disciplined way to introduce change without starting from scratch each time.

Scalability means preserving the ability to choose

There is a reasonable objection to all of this: flexibility creates complexity. For a small application performing one stable task, designing an elaborate system that can work with numerous models may not make sense. We don't need to make everything portable simply because we can.

A better principle is to preserve flexibility where being inflexible later could become expensive or disruptive.

Think about renovating a house. You don't design every wall so it can be moved tomorrow. That would be expensive and unnecessary. But you probably don't want critical plumbing somewhere that requires demolishing half the house to reach it either. The same principle applies to AI.

The AI market is changing too quickly for organizations to assume that today's preferred model will always be tomorrow's preferred model. We don't need to predict exactly what will happen. We need to avoid designing ourselves into a corner.

For CROs and site networks moving AI from pilots into real operational use, model-agnostic architecture is therefore less about avoiding commitment and more about preserving the ability to make a better commitment later.

If your primary AI provider changed its pricing, limits, capabilities, or model portfolio tomorrow, how much of your clinical AI environment would you actually have to rebuild?

The model is a component, not the architecture. Build the application around your workflow, not your vendor.