What I Got Wrong About "Just Give It a Better Model"

For the first few weeks I assumed the failures were the model's fault. It was the easy explanation and it also meant the fix was someone else's job.

Then I counted. About 18% of the failures I logged were actually model errors. The rest were state, permissions, and tasks whose finish condition was never written down.

The three model swaps I did anyway

To be fair to the instinct, I did swap models three times. Each swap did something real:

• The first one fixed a class of malformed tool arguments. Genuine improvement, visible in a week.
• The second fixed tone on writing tasks so the drafts stopped needing a rewrite. Worth it, but it also made me notice the writing tasks were the ones I should not have delegated in the first place.
• The third fixed nothing observable and cost more. I kept it for a month out of sunk-cost stubbornness before going back.

That is the shape of it: better models fix the failures that are actually the model's. They do not touch a wrong branch, a held port, or a task that ends whenever the agent feels it is done.

The trap in the framing

"Just use a better model" sounds like advice about tooling. In practice it is often advice about avoiding the boring part, which is describing the task and the state well enough that a cheap model could do it.

I have watched myself buy tokens to avoid writing five lines. It works, briefly, and then the same failure comes back at a higher price point.

What the better model is genuinely for

I am not arguing against it. When the remaining failures are concentrated in tool selection and multi-step reasoning, a better model moves the needle immediately, and the money is well spent.

The point is order. Pin the state, write the finish condition, define the permission edges, then upgrade the model if there is anything left to fix. Doing it in the other order means paying to run the same failures faster.

If you have done a swap recently, did it fix something you could point at afterwards? Mine did, twice out of three times, and the two that worked were the two where I already knew exactly which failure I was trying to kill.