Per-turn model routing can cut coding-agent costs without changing the agent
entelligenceai17 · reddit · 2026-07-23
A team found that using frontier models like Claude Opus, GPT-5.5, or GLM-5.2 for every agent turn is overkill because most turns are routine file search, test reruns, and code edits.
Their approach
They built a per-turn router that:
- keeps cheap models on routine steps
- escalates only hard turns to stronger models
- leaves the agent architecture unchanged
What they measured
They benchmarked the router against direct Opus, Sonnet, and OpenRouter Auto on Terminal Bench, and published details on:
- routing logic
- cache behavior
- cost breakdowns
The main idea is that agent sessions do not need to be locked to one expensive model from start to finish; smarter turn-level routing can preserve quality while cutting spend.
Related event: Cursor Launches Router for Dynamic Model Selection(9 posts)→
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