Cmd. /effort
Set or inspect model-specific reasoning effort.
Key takeaways
- Set or inspect model-specific reasoning effort.
- Check the input surface and availability before using the examples below.
Purpose
Set or inspect model-specific reasoning effort.
/effort [level|auto|status]Availability
| Field | Value |
|---|---|
| Input surface | Running CLI prompt |
| Kind | Built-in |
| Status | Current reference |
| Aliases | — |
| Documented minimum | Not specified |
| Reviewed against | 2026-09-22 · Claude Code 2.1.278 |
Use a level supported by the model. In -p on v2.1.205+, changes are session-scoped; Fable 5, Opus 4.8, and Opus 4.7 retain their defaults for this slash change, so use --effort.
Examples
/effort statusEffects and persistence
Adjusts reasoning effort for the active model. Session-only values and saved defaults depend on the model, level, and input surface.
Inspecting or resetting effort
Use /effort status to inspect the active level. /effort auto returns to the model default. Supported levels differ by model; check the model configuration reference before selecting one.
Cautions
max and ultracode can be session-only selections; explicitly configured ultracode has different persistence. Check the model-specific rules.