it seems to have changed a ton in recent versions too — I would love more details on what exactly

I find it doing what I in the past had to interrupt and tell it to do fairly frequently now

For one thing it seems to splitting up the work and making some determination of complexity, then allocating it out to a model based on that complexity to save resources. When I run Claude with Opus 4.5 and run /cost I see tokens for Opus 4.5, but also a lot in Sonnet and Haiku, with the majority of tokens actually being used by Haiku.

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nyellin a day ago | parent [-]

Haiku is called often, but not always the way you think. E.g. every time you write something CC invokes Haiku multiple times to generate the 'delightful 1-2 word phrase used to indicate progress to the user' (Doing Stuff, Wizarding, etc)

	▲	dkdcio a day ago \| parent [-]
		it’s also used in the Explore agent and for other things too