defaultModelForTier function

String defaultModelForTier(
  1. AgentTier tier
)

The model tier rides when the station arms none — the ASSET rung, the bottom of the model ladder.

ALWAYS an explicit model id, never null: an unpinned claude resolved to opus and then SILENTLY fell back to fable once the weekly limit blew (2026-07-11), so no rung of this ladder is allowed to return nothing.

Implementation

String defaultModelForTier(AgentTier tier) => switch (tier) {
  AgentTier.cheap => kCheapModelDefault,
  AgentTier.mid => kMidModelDefault,
  AgentTier.frontier => kFrontierModelDefault,
};