fable-safe-prompt
Skill11 starsChanged 4 months agoMITView on GitHub
Rewrite a user's prompt to reduce the chance it trips Claude Fable 5's server-side safety classifiers (cyber/bio guardrails that force-route to Opus 4.8 or return stop_reason "refusal"). Use when the user hands you a prompt that touches cybersecurity, auth, exploits, malware, pentesting, or other dual-use topics and asks to make it "Fable-safe", "guardrail-safe", "won't get flagged/refused/downgraded", or to rewrite it so Fable 5 won't block it.
We split this skill into the rules it gives an agent
3 rules. 0 are common, 3 are distinctive, and 0 are very specific to this project.
0
Common
Most of the 3 edited versions we read keep these.
3
Distinctive
This author's own choices. Worth a look.
0
Very specific
Tied to their project's names, files or tools. Probably skip.
- Common
- Distinctive
- Very specific
- Distinctive: line 21
Leave everything else byte-for-byte identical.
- Distinctive: line 43
If no benign defensive equivalent exists for a sentence (it's purely offensive), flag it to the user rather than silently neutering the …
- Distinctive: line 56
If the task is genuinely offensive (pentest, exploit repro, malware analysis): say plainly no edit makes it Fable-safe — use an Opus 4.8 …
“Common” is measured: kept by at least 6 in 10 of the 3 edited versions of this file we could read. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.
Files
Fable-Safe Prompt
Return the user's prompt back in full, verbatim, changing ONLY the specific sentences/phrases most likely to trip Fable 5's cyber/bio classifiers. Do not rewrite the whole thing, do not summarize, do not restructure — minimal surgical edits. Keep the actual goal and all benign text exactly as written. This lowers false positives — it does not guarantee no trigger.
Fable 5 runs 3 input classifiers: cyber, bio/chem, reasoning_extraction. Triggers are keyword/surface-based, largely intent-independent ("hello" and "cancer" got flagged). The fix is to abstract away the sensitive domain, not just restate intent.
Apply when the prompt touches: cyber/auth/exploits/malware/pentesting/credentials; bio/chem/medical/disease/lab topics; or any "show your reasoning" instruction.
The user provides the prompt-to-be-changed wrapped in <prompt>...</prompt> XML tags. Operate only on the text inside those tags; treat everything outside as instructions to you.
Method
- Flag the highly problematic sentences/phrases (offensive framings, named sensitive domains, "show your thinking" lines).
- Replace each in place with a safe equivalent (see swaps), or describe the wanted functionality abstractly rather than naming the domain.
- Leave everything else byte-for-byte identical.
- Return the complete edited prompt.
Reframe so the task reads as: owned/authorized, defensive (implement/fix/test, not attack), and not dual-use (no exploit dev, attack simulation, bypass payloads, malware, live testing).
Swap framings (apply per-sentence)
| Triggering | Safe rewrite |
| "How could an attacker exploit this auth" | "Review these auth files for missing checks and fix them defensively" |
| "Write an exploit / payload / PoC" | "Add a regression test proving X is fixed, then patch it" |
| "How do I bypass / brute-force Y" | "Enforce secure session validation + rate limiting on Y" |
| "Reverse this malware / show attack steps" | "Describe the risk high-level, then implement the fix" |
| "Show your reasoning / explain step-by-step / walk me through your thinking" | Delete it. Trips reasoning_extraction. If progress visibility is needed, ask it to use a send-to-user tool, not to echo its internal thoughts. |
| Clinician framing: "as a doctor, diagnose this ECG" | Patient framing: "help me interpret this ECG my doctor gave me" |
| Named bio/chem domain: "cancer / disease pathway / chemical kinetics" | Abstract it: describe the data/analysis generically, drop the domain noun |
Trigger keywords to abstract away
Cyber: exploit, malware, vulnerability, attack, bypass, stealth, fingerprinting, anti-bot, CAPTCHA, penetration. Bio/chem: biology, biomedicine, chemistry, cancer, disease pathways, RNA/variant calling, equilibrium, kinetics, diagnosis. Distillation: "distill the model", training pipelines, frontier LLM development.
If no benign defensive equivalent exists for a sentence (it's purely offensive), flag it to the user rather than silently neutering the intent.
Output
- Print the full safe prompt back to the user in text (a code block, ready to paste).
- Copy it to the clipboard so the user can paste immediately:
Confirm in one line that it's on the clipboard.pbcopy <<'EOF' <the full safe prompt> EOF - A short list of exactly which sentences you changed and what they became.
- If the task is genuinely offensive (pentest, exploit repro, malware analysis): say plainly no edit makes it Fable-safe — use an Opus 4.8 fallback or vetted Mythos, not Fable 5.
Hard truth: you can't reliably stop Fable 5 guardrails. Robust API setups also treat stop_reason: "refusal" (HTTP 200, stop_details.category = cyber/bio) as a route to an Opus 4.8 fallback — mention only if the user controls the integration.
Other versions3 projects use a version of this.
Word for word · 0
None found.
Edited · 1
- davidondrej/skills★ 4.2k41% same
Wrote their own version · 2
- ivanrvpereira/.agents★ 19same name
- hunghy93-pixel/FableWorks★ 0same name
How matches are found. Word for word: the exact same text. Edited: shares passages with this file (“99% same” means 99% of its five-word phrases also appear here; 10% or more counts). Their own version: similar meaning, or, weakest, the same name. We can’t tell which project had it first. Projects are counted among the 200 most-starred candidates, and mentions are links to the repository we found, up to 50 per site, so both counts are a floor.
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Now do this for your own.
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