Anthropic’s configurable reasoning budget hierarchy for Claude models. Controls how many reasoning tokens the model allocates per turn.
Hierarchy
none → low → medium → high → max → X high (Opus 4.7 exclusive)
Key points
- Effort levels control thinking depth, not model weights [010]
- Opus 4.6 was silently set to “medium” default on 2026-02-09 via adaptive thinking parameter changes — not a model weight change. This caused the widespread reports of Opus 4.6 degradation [010]
- “X high” is exclusive to Opus 4.7 — Anthropic’s stated maximum reasoning allocation [010]
- Higher effort = more thinking tokens = more expensive. The “ultra think” keyword in Claude Code allocates maximum thinking budget (~32K tokens) before responding [011]
- Community guidance: use “X high” / “ultra think” for architecture decisions and hard debugging; use lower effort for routine tasks to preserve quota [011]
Related entities
- Claude Opus 4 7 — introduces X high level
- Anthropic — defines and controls the effort hierarchy
Related concepts
- Adaptive Thinking — mechanism that selects effort level per turn
- Token Economics — effort level is the primary lever on reasoning token spend
Source references
- [010] Nate Herk — Cloud agents & model releases cluster (2026-04-14 to 2026-04-17)
- [011] Nate Herk — Claude Code power features cluster (2026-04-20 to 2026-04-27)