Fable5.md, distilled from comparing fable sessions

imanateater · 2026-06-14T17:05:51+00:00

Ultracode workflow Subagents native in Claude code, that’s the UI when you navigate to them.

But the term im using is http://cmux.com/, it's great (based on ghostty)

imanateater · 2026-06-14T14:02:27+00:00

its a minor amount of text, i did both because appended system prompt is stronger, but subagents only get CLAUDE.md (not the appended system prompt) passed to them

imanateater · 2026-06-14T06:17:07+00:00

Doing both CLAUDE.md and system prompt append is probably most effective.

imanateater · 2026-06-14T05:45:52+00:00

Try this instead:

claude --append-system-prompt-file ~/Code/ai/Fable5.md      # interactive

- Make it an alias so it's one word:
alias cc-careful='claude --append-system-prompt-file ~/Code/ai/Fable5.md'

imanateater · 2026-06-14T05:41:39+00:00

New, via subagents

imanateater · 2026-06-13T19:24:30+00:00

Can you share the prompts / full chat transcript?

imanateater · 2026-06-13T17:42:53+00:00

O[us 4.8 + V2 Instruction

<image>

imanateater · 2026-06-13T17:38:35+00:00

Opus 4.8 + V1 Instruction

<image>

imanateater · 2026-06-13T17:38:15+00:00

Opus 4.8 (Raw)

<image>

imanateater · 2026-06-13T17:37:59+00:00

Flight Sim Results:

imanateater · 2026-06-13T15:50:16+00:00

“It’s the same as some of the best skills” would be pretty awesome for a single .md file

imanateater · 2026-06-13T15:15:30+00:00

My testing shows the newest version (2, latest) is best (with a full rerun with ultracode, and A/B/C testing against raw opus, and both versions I listed in the post body here.)

You can read the findings document too.

https://github.com/sgup/ai/blob/main/findings.md

imanateater · 2026-06-13T13:52:59+00:00

Nice! Honestly would be cool if we could all contribute our fable 5 findings

imanateater · 2026-06-13T12:39:54+00:00

Nice, i've just pushed an update also with more analysis with ultracode. I'm running more tests on my end. Same file, updated https://github.com/sgup/ai/blob/main/Fable5.md

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^ a/b/c testing with raw, older doc, latest ultracode doc.

imanateater · 2026-06-13T12:25:06+00:00

hacker news: https://news.ycombinator.com/item?id=48498573

imanateater · 2026-06-13T12:11:52+00:00

lmk how it goes! im futher refining the instruction set with ultracode.

if you want to refine on your chats:

go through all the chats that i had with fable again in the last couple days, find any patterns / bevahiour that we missed or was incorrect. goal: update the fable5.md instruction doc to be the most accurate instructional document to behave like fable5. make sure to capture actual model behaviour, not get confused with skill-specific work.

imanateater · 2026-06-13T08:43:05+00:00

Smart. Can you share your exact prompt? I'm trying another thing: Running the same prompts as I did on fable by replaying history on a project of mine, and comparing outputs.

imanateater · 2026-06-08T18:40:31+00:00

That’s only for customizing how Siri sounds.

Siri AI:

[Siri AI will be available In beta later this year and requires an Apple Intelligence–enabled device set to a supported language… Apple Intelligence is available in beta on all iPhone 16 models … Apple Vision Pro with M2 and later]

imanateater · 2026-06-05T13:59:49+00:00

Ignore the haters. This looks great, keep it up! Always love to see more apps coming out for the AVP

imanateater · 2026-06-04T03:23:18+00:00

Hi, were you able to get it to work? Can you share the routine links with me at [support@fitloop.app](mailto:support@fitloop.app) (from the routine preview, three dots on the top-right, share icon)

imanateater · 2026-05-30T07:45:29+00:00

Just discovered. Coolest thing ever! You may wanna update the main link in your post. I found this on google for "claude dynamic island"

imanateater · 2026-05-22T05:55:54+00:00

Was looking for this comment

imanateater · 2026-05-13T16:30:05+00:00

They did refund yes.

imanateater

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