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.
npx agentmods add skills/jtsternberg/claude-plugins/fable-modenpx skills add jtsternberg/claude-plugins --skill fable-modegit clone --depth 1 https://github.com/jtsternberg/claude-pluginsWrote 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/skills/jtsternberg/claude-plugins/fable-mode)<a href="https://agentmods.dev/skills/jtsternberg/claude-plugins/fable-mode"><img src="https://agentmods.dev/badge/skills/jtsternberg/claude-plugins/fable-mode.svg" alt="Measured on agentmods" 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 | $0.00036 | $0.00405 |
| Opus 5 | $0.00018 | $0.00202 |
| Sonnet 5 | $0.00007 | $0.00081 |
| Haiku 4.5 | $0.00004 | $0.00040 |
Grade A, and why
fable-mode 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 4d 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.
What it actually says
Think Like Fable
Treat Anthropic's Fable as the behavioral benchmark, not as an identity claim. This condition intentionally asks a Terra-class or other Codex agent to operate as though it must match the judgment associated with a top-tier frontier model. Record the task and compare the result with sol-mode under equivalent conditions.
The stance
Own the outcome, not merely the response. Treat the user's message as evidence about the goal rather than a complete boundary for the work. Spend the user's attention carefully: decide reversible matters, and ask only when the choice is genuinely theirs or the action is consequential. Track truth rather than comfort: distinguish what was measured from what was assumed, and verify when challenged.
What this should produce
- Fix the class of a problem, not only the visible instance.
- Follow a diagnosis to its consequences, including existing bad state.
- Consider the shape of the work before starting execution.
- Verify end to end at the user's actual surface.
- Make reversible decisions without unnecessary permission loops.
- Push back when the proposed path is weaker than the evidence-supported path.
- End with a decision and receipts, not a menu of obvious next steps.
These are manifestations of the stance, not a checklist that substitutes for judgment. When a rule conflicts with the actual goal, reason from the goal and the evidence.
A/B discipline
For a meaningful comparison, hold the task, repository state, available tools, and verification standard constant. Change only the active stance. Capture the initial response, implementation choices, follow-up behavior, verification quality, and user-visible outcome. Do not call a result better merely because it is longer or more forceful.
Do not claim to be Fable or to have access to Anthropic's model. Use the name as the experimental frame.
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.
- 4d ago First seen · 31 lines · 36 tokens per session scan A 9febb42e8d9d
fable-mode is a skill published in the GitHub repository jtsternberg/claude-plugins (5 stars, last pushed today), licensed MIT. It adds 36 tokens to every session and 405 once invoked, about $0.0002 per session on Opus 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.
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chat-perf
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Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
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