FG—01AI Design Field Guide

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PTN—13

Model management

Frame model choice as a tradeoff people can reason about — fast versus thorough — not a benchmark menu.

Model pickers are where products quietly leak their org chart. A dropdown of version numbers and codenames — each one a benchmark bragging right — asks users to make an engineering decision with marketing information. Nobody outside the vendor knows what separates one alphanumeric soup from another. What people can reason about is a tradeoff: fast and cheap versus slow and thorough. Model management is the discipline of translating the roster into that language.

The translation is task-shaped, not spec-shaped. “Best for quick answers” and “takes longer, reasons deeper, costs more” are decisions a person can make in two seconds; context-window sizes and eval scores are not. And because most people should not have to decide at all, a recommended default — visibly marked — carries the load: choosing becomes optional, an escalation for the requests that deserve it rather than a toll on every message.

The choice must then stay legible. A model selected three messages ago is invisible state, and invisible state is how someone burns premium credits on small talk or trusts a fast model with a hard problem. Show the active model persistently during the conversation, not just in the picker. And when someone switches mid-task, say what carries over — the conversation history travels, but the new model has none of its predecessor’s in-flight reasoning, and pretending otherwise sets up a betrayal.

The pattern’s trajectory points toward its own disappearance: automatic routing that picks the engine per request, with manual choice as the override. That makes the honest framing more important, not less — a router is a recommendation the system makes silently, and users will only trust it if the manual picker taught them the tradeoff space first.

Anatomy

Fig. 01Model managementLive specimen

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A model picker framed as tradeoffs, with a marked default and the active choice visible in the conversation.

  1. 1Task-language tradeoffs. Each option states speed, depth, and cost in plain terms — model names alone decide nothing.
  2. 2Recommended default. One option is visibly marked as the default, so choosing is an override, not a prerequisite.
  3. 3Persistent active choice. The current model stays visible during the conversation, not just inside the picker.
  4. 4Switch carry-over notice. Switching mid-task states what travels — history carries, in-flight reasoning does not.

When to use

Design considerations

Pitfalls

In the wild

Claude
The model picker pairs each option with a one-line purpose — fast for everyday tasks, more capable for complex work — instead of specs alone.
Cursor
An Auto mode routes requests to an appropriate model by default, with the manual picker as the power-user override.
v0
Model tiers are framed by size and cost tradeoff, and the active tier is visible where generation happens.

Principles served