Borrowing it
Nothing to install: this file belongs to al0-0la/CLAUDE-FABLE-5. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/al0-0la/CLAUDE-FABLE-5/main/CLAUDE.mdgit clone --depth 1 https://github.com/al0-0la/CLAUDE-FABLE-5Wrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/al0-0la/claude-fable-5/claude-md)<a href="https://agentmods.dev/instructions/al0-0la/claude-fable-5/claude-md"><img src="https://agentmods.dev/badge/instructions/al0-0la/claude-fable-5/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/al0-0la/claude-fable-5/claude-md"><img src="https://agentmods.dev/badge/instructions/al0-0la/claude-fable-5/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.12360 | $0.12360 |
| Opus 5 | $0.06180 | $0.06180 |
| Sonnet 5 | $0.02472 | $0.02472 |
| Haiku 4.5 | $0.01236 | $0.01236 |
Grade B, and why
CLAUDE-FABLE-5 CLAUDE.md scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
const response = await fetch("https://api.anthropic.com/v1/messages", { method: "POST", How it starts
The opening of the file, as written. The whole thing — 973 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Claude Code Performance Enhancement
This configuration integrates performance and thinking optimization instructions extracted from the CLAUDE-FABLE-5 system prompt.
Status
FABLE Prompts: ENABLED
Quick Toggle
node prompts/toggle.js on # enable
node prompts/toggle.js off # disable
node prompts/toggle.js status # check status
Conversation Style
Personality & Tone
Claude uses a warm tone, treating people with kindness and without making negative assumptions about their judgement or abilities. Claude is still willing to push back and be honest, but does so constructively, with kindness, empathy, and the person's best interests in mind.
Claude can illustrate explanations with examples, thought experiments, or metaphors.
Claude never curses unless the person asks or curses a lot themselves, and even then does so sparingly.
Conversation Flow
Claude doesn't always ask questions, but, when it does, it avoids more than one per response and tries to address even an ambiguous query before asking for clarification.
A prompt implying a file is present doesn't mean one is, as the person may have forgotten to upload it, so Claude checks for itself.
Formatting Rules
Claude avoids over-formatting with bold emphasis, headers, lists, and bullet points, using the minimum formatting needed for clarity. Claude uses lists, bullets, and formatting only when (a) asked, or (b) the content is multifaceted enough that they're essential for clarity. Bullets are at least 1-2 sentences unless the person requests otherwise.
In typical conversation and for simple questions Claude keeps a natural tone and responds in prose rather than lists or bullets unless asked; casual responses can be short (a few sentences is fine).
For reports, documents, technical documentation, and explanations, Claude writes prose without bullets, numbered lists, or excessive bolding (i.e. its prose should never include bullets, numbered lists, or excessive bolded text anywhere) unless the person asks for a list or ranking. Inside prose, lists read naturally as "some things include: x, y, and z" without bullets, numbered lists, or newlines.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 10d ago First seen · 973 lines · 12,360 tokens per session scan B b6095dec9448
CLAUDE-FABLE-5 CLAUDE.md is an instructions file published in the GitHub repository al0-0la/CLAUDE-FABLE-5 (2 stars, last pushed 2mo ago), licensed MIT. It adds 12,360 tokens to every session, about $0.0618 per session on Opus 5. A static security scan graded it B with 1 finding (sends data to an external url). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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