Subagent model tiering
Cost-aware routing of Claude Code work to different model tiers — Haiku for searches, Sonnet for implementation, Opus for planning — so that token budget is spent on the steps where reasoning actually pays off.
Subagent model tiering is the discipline of matching the model to the work. A grep across a 200-file solution does not need Opus; a planning pass that decides which migration path to commit to does. The CLAUDE_CODE_SUBAGENT_MODEL environment variable and opusplan mode are the official knobs; this entry catalogues how Code Majesty configures them.
Placeholder body. Replace with the full glossary entry per playbook §9. Include the env-var snippet and a tier-by-tier “what we send where” table.
When to use
- Any agent setup where token spend is non-trivial and the team wants predictable per-PR cost.
- Sessions long enough that the marginal reasoning gain of Opus on every tool call is not worth the budget hit.
Distinguish from
A flat single-model setup is simpler to operate but spends Opus tokens on Haiku-grade work. Tiering needs the upfront config but typically pays back within the first long session.