What happened

The Wall Street Journal describes how businesses use software around AI models to supply context, manage tasks and choose which model handles a request. Moody’s has built this layer for its own tools.

Why it matters

Control over this software can help a company protect workflows and change providers. Routing tasks between models also gives it a way to manage spending.

There is a trade-off between building this layer internally and using one supplied by a vendor. An internal system can keep more control within the business, but a vendor’s system can spare the team from rebuilding common infrastructure.

The article presents both approaches. It describes Moody’s ability to change the underlying model and Bristol-Myers Squibb’s decision to use Claude as its shared foundation.

What this does not tell us

These are reported company choices and explanations, not a controlled comparison of costs or reliability.

FOR PEOPLE

Benefits reported

In-house harnesses let teams direct models, protect workflows, switch providers and reduce dependence and token costs.

FOR AI AND ITS OPERATORS

Benefits and downsides

Harnesses give agents memory, business context, code execution and workflow reach; routers and controls limit which models act and how much they spend.

These are two separate readings of what the sources describe. Reported claims and risks do not by themselves establish a real-world effect.

Original sources · 1
  1. Introducing the AI Model ‘Harness’ ↗WSJ · 2026-08-24

Reporting discovered in United States. Discovery market does not mean the event happened there.