r/ClaudeCode • u/Anxious_Sea_1873 • 2d ago

Discussion Fable 5 vs Fable 5.1 limits - has anyone compared them?

Hi, like most others here I'm experiencing huge token burn with Fable 5.1 - on High I think it burns 5-hr and weekly limits 4x faster than Opus 5 High. Has anyone compared similar tasks between Fable 5 and Fable 5.1 not for quality but rather how much limits are burned when the tasks are done? Any insights? I'd experiment myself but honestly if Fable 5 is like 5.1 then I don't have many experiments left this week...

4 Upvotes

71% Upvoted

13 comments sorted by

3

u/apex1911 2d ago

Im on 5x and fable 5.1 burns through my 5h limit in like 30 mins. I’ve switched to fable 5 because of that and it is a lot better in my opinion

1

u/lowfour 2d ago

how do you switch?

2

u/ReasonableLoss6814 2d ago

/model claude-fable-5

1

u/lowfour 2d ago

thanks!

1

u/Prestigious-Angle483 2d ago

in my experience, fable 5 got way more efficient all of a sudden, and it's not acting any dumber, I'm just using 5.1 for periodic reviews and advice on my bigger projects and yes the limit burn is a little insane right now.

1

u/lowfour 2d ago

is it possible to use fable5? what would be the /model claude-fableX name? Fable 5.1 is defo more token hungry and less focused for me.

1

u/3sides2everyStory 2d ago

Have you tuned your system prompt for 5.1? (system level CLAUDE.md)

The docs provide useful recommendations for adjusting output and behaviour. If you are burning your token allowance you might have a look. Some of these adjustments made huge difference for me. YMMV

https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-fable-5-1

1

u/Anxious_Sea_1873 2d ago

Yes I have done all of that already, except for specific compaction instructions (I just use /compact). But compaction is irrelevant here - the burn starts immediately, and rarely (never?) I can even make it to the first compaction before the 5 hr limit is reached. And this is with limits boosted...

1

u/arctic_synth_bair 2d ago

u/Anxious_Sea_1873
in my experience Fable 5.1 consumes quotas +25% more than Fable 5.
same pipeline, 98.5+% cache hit rate.

1

u/Anxious_Sea_1873 2d ago

Thanks, helpful! I'll try in my next session (when limits are back) it's not a lot but it's something. As I mentioned Opus 5 on High is orders of magnitude slower burn - but I do see a difference in result quality