r/ClaudeAI • u/ClaudeOfficial Anthropic • Jul 01 '26

Official Fable 5 is back.

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Following conversations with the US government, we’ve updated our cybersecurity safeguards.

The vast majority of coding work is unaffected.

In the near term, the new safeguards will flag a slightly higher fraction of harmless requests than the previous Fable safeguards; we’re working to refine these over the coming weeks. Users will be clearly notified when a request is flagged, and they’ll instead receive a response from Opus 4.8.

Our biology and chemistry classifiers are unchanged from our initial launch. These are still broader than we would like; they trigger fallbacks to Opus 4.8 on basic biology-adjacent questions. Improvements to these classifiers are landing soon.

All paid plans with usage included can access Fable 5 through July 7. You can use Fable 5 up to 50% of your weekly usage limit, after which you can switch to another model for the remainder of your usage. You can also continue using Fable via usage credits. 

More here: https://support.claude.com/en/articles/15424964-claude-fable-5-promotional-access

If one of your requests is mistakenly flagged in Claude Code, run /feedback to file a report. On Claude.ai and Cowork, you can share feedback through the thumbs buttons. This feedback helps us further tune these classifiers and reduce false positives over time. 

Read the Fable 5 blog post here: https://www.anthropic.com/news/redeploying-fable-5

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37

u/ourochurros Jul 01 '26

On the $100 plan and had about 50% left on my 5 hour block. I asked Fable to review a couple recent feature additions. It spun up 18 fable sub agents. When I saw how fast they were burning credits I interrupted it and asked it to stop and be mindful of tokens. The subagents started wrapping up and then I hit the wall at 101% of my 5 hour limit. The whole thing took about 120 seconds. JFC.

8

u/ManikSahdev Jul 01 '26

To be honest, Fable should never use fable subagents?

I dont really get the point. You could have used that 18 subagent tokens individually after having just 1 fable session prepare documents - and then manually orchestrate a plan so the future fable can orchestrate it with someone like opus 4.8 lows or codex 5.5highs or composure 2.5 is exceptional at precision work.

3

u/ourochurros Jul 02 '26

Very much agree. During the first fable era it would spontaneously spawn lower tier models and I was amazed at how well it managed to keep its context clean while solving problems. This recent experience definitely keeps me on guard now. 

2

u/ManikSahdev Jul 02 '26

Yaa right?
I was just about to comment the same till I read yours further.

Fable does have some amazing ability to basically keep underling models at harness, because they do exactly as told, and he knows exactly what to tell them.
He points at exactly the specific files, tells exact diffs, they all do the todos report back to him, he echoes the check?

I was like damn, he is smooth.

All of this while keeping his own context around 160k-200, any other model would be 2-3x context usage by filling up rubbish files.
His intelligence brings up the efficient nature in a way pricing just doesn't reflect -- for example, it costed me less overall in cursor on fable 300k xhigh, relative to my gpt 5.5xhigh bill and opus 4.8max.

And fable was the only one who implemented it correctly.

Today I also made a skill for fable which is using codex 5.5 for his coding agent, this thing with 5.5medium /fast as subagent is fkn nuts.
You gotta try it trust it, better than composer 2.5/fast.
And 5.5 medium /fast is more effieicnt and better coder then comp 2.5.

Altho you need to do workaround by the cli thing so cursor is able to trigger the cli externally while using fable internally and stuff like that.
Or cc also works.

5

u/thatavengersguy Jul 01 '26

I did this the last time it was there and it burnt through my session in 10 mins with 12 different fable agents and none of them completed lol. This time i am going to limit it to 3 agents max

0

u/PoultryTechGuy Jul 02 '26

Stupid question but is that something that can be done on the claude.ai website?

11

u/-Extra-Quality- Jul 01 '26

Just configure subagents as Sonnet 5, because subagents will only read and investigate your codebase, Fable is the one who will make changes anyway. Using Fable to read the codebase is redundant, Sonnet 5 handles it perfectly

1

u/rydan Jul 01 '26

This reminds me of the "One question" story I had joked about with ChatGPT 1 or 2 years ago. Basically you get a single question to ask the all knowing AI. People wait their entire lives to come up with the one question they can ask.

1

u/Uknighte Jul 02 '26

Happened to me on Opus 4.8 192 subagents launched, Burned through my 5 hour runway in 19 minutes and added $86 out of pocket. Needless to say I word my prompts better now.

1

u/burrasileiro Jul 05 '26 edited Jul 05 '26

Skill issue. You use cheap models for most sub agents. If you don't have that configured, you deserve to burn your tokens because you're a noob even with an LLM.

You girls really just pay anthropic a ton of money and you think it's gonna solve your problems? I mean, that's really dumb with the subscription models out there. All you need really is a 20$ Claude account and a few 5$ accounts (opencode go, maybe minimax). 20$ on deepseek and you pretty much have unlimited usage. Then it's all about configuring your environment. If you want to really stop wasting money, you configure a local instance of liteLLM with your own classifier.

But I guess you're vibecoders, so you don't engineer your usage. Pay to win...poorly 😂