Models & effort levels

Two dials control how much brain Claude brings: which model, and how much reasoning effort it spends. Set both from `/model`. Today's lineup is Opus 4.5 (deepest), Sonnet 4.5 (the daily driver), and Haiku 4.5 (fast and cheap).

/model              # pick model + effort level
claude --model opus  # one-off session

• ✓Opus 4.5 — hardest reasoning, highest cost
• ✓Sonnet 4.5 — best default for everyday coding
• ✓Haiku 4.5 — fast, cheap, great for small mechanical edits
• ✓Effort level is a setting now, not a magic prompt word