Claude Fable 5.1: Max effort wins

5 reasoning levels; max produced the most detailed SVG pelican

Proof	In Simon Willison’s SVG test, max used 65,927 output tokens including reasoning and took 13 minutes 54 seconds.
Best for	Coding, knowledge work, and long-running problem-solving tasks
Available via	Anthropic API
Try it	Ask for an SVG of a pelican riding a bicycle at 'max' reasoning effort

Key takeaways

Why it matters: In this single SVG test, higher reasoning effort produced more detail but used more tokens and took longer.
Before you switch: For the same SVG prompt, low and medium showed no reasoning text and finished in about 23 seconds; results may differ on other tasks.