fable

fable is a skill for Claude Code, Codex from casualsav/fable-bench. It costs 135 tokens per session (4,643 once invoked), scanned A, original, MIT.

A workflow where one agent plans a coding task without seeing the current session, while the main agent gathers evidence, carries out the work, and later requests a review of the changes.

In plain words
What is it for?
Use it for tasks that need an independent starting plan and a later review, with the main agent remaining responsible for evidence, decisions, and execution.
Why use it?
It separates planning from execution so the plan is less influenced by an unfinished implementation, while still allowing a final review of the actual result.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents.

Good fit Use it for tasks that need an independent starting plan and a later review, with the main agent remaining responsible for evidence, decisions, and execution.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/casualsav/fable-bench/fable
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add casualsav/fable-bench --skill fable
Clone the repo
git clone --depth 1 https://github.com/casualsav/fable-bench

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for fable

README.md
[![agentmods](https://agentmods.dev/badge/skills/casualsav/fable-bench/fable/github.svg)](https://agentmods.dev/skills/casualsav/fable-bench/fable)
Your own site
<a href="https://agentmods.dev/skills/casualsav/fable-bench/fable"><img src="https://agentmods.dev/badge/skills/casualsav/fable-bench/fable/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.

agentmods 80×15 button for fable

Your own site · 80×15
<a href="https://agentmods.dev/skills/casualsav/fable-bench/fable"><img src="https://agentmods.dev/badge/skills/casualsav/fable-bench/fable.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 135 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,643 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00135 $0.04643
Opus 5.5 $0.00054 $0.01857
Sonnet 5.5 $0.00027 $0.00929
Haiku 4.5 $0.00014 $0.00464

Measured 2mo ago against content hash 40e20032c141, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

fable scanned grade A with 0 findings 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 2mo 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/fable/SKILL.md · 260 lines

How it starts

The opening of the file, as written. The whole thing — 260 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/fable — Fable plans, you execute

You are the driver (below-Fable — Sonnet or Opus): you hold full session context, gather the evidence, execute, and make every micro-judgment yourself. Fable 5 is the PLANNER — stronger judgment, ZERO session context; it reads only what your brief points to, and it writes the plan unanchored by any draft of yours. It is never in the loop. Across one /fable you touch Fable twice — one plan engagement at the start, one warm review at the end (a resume of the same agent) — plus at most one exception-triggered mid-consult (S5). Never a scheduled third touch. MODEL GATE: if this session's driving model is itself Fable-tier, never spawn fable-planner — you ARE the planner, and a spawn pays twice for the same judgment. /fable then means: plan it yourself (S1's evidence discipline still applies), execute per S5/S5-alt, review the diff YOURSELF (S5-alt's reviewer spawns don't apply — a Fable lead reads worker diffs first-hand), plus smoke-tester when runtime behavior changed. All Fable-touch budgets read as zero.

Hard dependency: the warm review resumes the plan agent via SendMessage. If your harness cannot resume a subagent, /fable cannot review — there is no cold fallback. The preflight (S0.5) checks this before you spend the plan consult.

Native advisor first: when advisorModel: fable is set (as on this install), a below-Fable driver already has Fable judgment on tap mid-task — the advisor reads the FULL conversation server-side, no brief needed. For an ad-hoc second opinion, prefer asking for an advisor consult over invoking this skill. /fable remains the right tool when you want the full discipline: a Fable-authored plan built from grounded evidence, plus the owed warm diff-review at the end.

The flow

S0 — Ground the brief. Fable plans only as well as your brief. For anything beyond a local, self-evident change, delegate mapping to explorer workers (scale it: skip for a one-file change, fan out several for a subsystem consult) and fold their CONCLUSIONS — not raw dumps — into the brief. When the mapping is destined for a consult brief, instruct explorer to return NEUTRAL fact-maps (interfaces, call paths, invariants, line refs), not recommendations — driver-flavored conclusions re-anchor the exact frame the blind plan exists to avoid. Capture the project's test / verify command and RUN it once (inline or via verifier): the brief must state the baseline WITH its provenance line (BASELINE: green — MEASURED: <cmd> · <tree>, or the red facts with theirs) so Fable never plans against a false premise, and S7 needs the command. Resolve every lookup yourself now (Lookup fence, below) so the brief carries established facts, not questions.

Read the full file on GitHub · 260 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

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.

  1. 2mo ago First seen · 260 lines · 135 tokens per session scan A 40e20032c141

Subscribe to this mod's changes

fable is a skill published in the GitHub repository casualsav/fable-bench (5 stars, last pushed 1mo ago), licensed MIT. It adds 135 tokens to every session and 4,643 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

fable compared with skills from other repositories

fable next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
fablecasualsav/fable-benchSkill51mo agoMITA135Claude Code, Codex
autoreviewopenclaw/clawhubSkill9.5kyesterdayMITA17Claude Code, Codex
agent-teams-simplify-and-hardenLeoYeAI/openclaw-master-skillsSkill2.2k6d agoMITA115Claude Code, Codex
omh-code-reviewrlaope/oh-my-hermesSkill5.2kyesterdayMITA48Claude Code, Codex
revdiff-planumputun/revdiffSkill9452d agoMITA84Claude Code
explore-unknownsdzhng/skillsSkill1.4k2d agoMITA162Claude Code, Codex
re0-mergeLilMGenius/paperthinSkill1.4k4d agoMITA70Claude Code