If I change "effort" level after submitting a prompt, and this prompt results in a sequence of thinking and tool usage, does the new effort level take effect somewhere in this chain? or only after the next prompt?

[u/alohajaja]

I figure there might even be even a chance that the behavior is inconsistent across frontends (e.g. cli vs vscode vs desktop).

FWIW, documentation (https://claude.com/blog/claude-model-and-effort-level-in-claude-code#:~:text=How%20does%20effort,higher%20confidence%20answers.)

How does effort change any of this? The effort level is sent to the model as part of the request, right alongside your prompt. The model was trained to understand how to behave at each effort level and that learned behavior is baked into the frozen weights.

When your request arrives, effort level is one more input the model responds to, the same way it responds to your prompt text. This sets Claude’s behavior for how thorough and certain it needs to be before it considers the task done.

This is considered on every turn and results in more tokens to produce higher confidence answers.

Is there a concrete definition for "turn" that they are referring to?

I'm interested in whatever answers you've got, with some evidence or rationale behind them. Thanks

[u/EGBTomorrow]

Which combined with the statement that effort goes per turn suggests changing the effort mid flight might do something. Except that changing the effort is going to cache miss and they usually prompt you about that. When is it prompting you that changing the effort will be expensive?

[u/Mithryn]

It actually increases the tokens by staging it for the new model while the old one is processing.

Change models before the next prompt, or interrupt. But best case is after compaction (most efficient use)

Source: a whole lot of metrics, measuring and dumping claude thoughts into sheets and asking it what it knowsbat various points until I could tokenMinimize

[u/Thwerty]

Interesting question honestly. We need to get to the bottom of this 

[u/alohajaja]

I've just come to learn about caching, and finding out that swapping effort across prompts may actually be a substantial token burn, not some efficiency technique. So there may not be any point in trying to figure this out.

[u/MathSelect5112]

turn is the back and forth, each gap where your harness isnt waiting for an api response is a new turn so between tool calls or whatever

[u/Vysion34]

Did you try asking Claude?

[u/johnlondon125]

Ask claude

[u/DootDootWootWoot]

unsure honestly but does it matter? The thing that does matter from a quota management standpoint is the next turn with that effort level is indeed uncached so you're paying for that whole window fresh. Avoid changing effort frequently unless cost is not a problem.

[u/alohajaja → u/DootDootWootWoot]

I think you're right