eyal-tools — Claude Code plugin

Everything for the "plan on Fable, code on Opus" workflow, plus a few extra skills, in a single Claude Code plugin.

Built on the work of JeredBlu. The prd-creator, mcp-evaluator, and agent-skill-evaluator skills — and the foundation of frugal-fable — come from his jeredblu-marketplace and his YouTube channel. Huge thanks — please check out and support his work. See Credits below.

Install (one marketplace, one plugin)

claude plugin marketplace add menaker/eyal-fable-optimizer
claude plugin install eyal-tools@eyal-tools-marketplace

Then restart Claude Code. That's it — you now have everything below.

Replace menaker/eyal-fable-optimizer with the actual owner/repo if this was forked.

What you get

Component	What it does
frugal-fable skill	Keeps Fable on the judgment and delegates heavy work to cheaper models. Includes the opt-in Fable-plan / Opus-build mode and the full-loop Fable-plan / Opus-build / Fable-verify mode.
/fable-opus command	Toggle the modes: /fable-opus on (build mode), /fable-opus verify (verify mode), /fable-opus off, /fable-opus status, or /fable-opus <task>.
SessionStart hook	Automatically re-asserts whichever mode was on after a context auto-compaction or session resume.
prd-creator skill	Create comprehensive PRDs through conversational discovery. (by JeredBlu)
mcp-evaluator skill	Security & privacy evaluation for MCP servers. (by JeredBlu)
agent-skill-evaluator skill	Security & safety evaluation for agent skills. (by JeredBlu)

Using "plan on Fable, code on Opus"

1. Set your session model to Fable (/model → Fable) — the planning half needs it.
2. Run /fable-opus on (or /fable-opus <your task>), or just say "plan with Fable, code on Opus" in a message.
3. From then on: Fable plans, decomposes, coordinates, and reviews; every code-writing slice is delegated to Opus subagents. Non-code grunt work (scans, logs) may still go to cheaper models.
4. It stays on across auto-compaction/resume until you run /fable-opus off.

Using "plan on Fable, execute on Opus, verify on Fable"

The full-loop variant of the mode above, for when you want maximum assurance and are willing to spend Fable tokens on it:

1. Set your session model to Fable (/model → Fable).
2. Run /fable-opus verify (or /fable-opus verify <your task>), or just say "plan on Fable, execute on Opus, verify on Fable" in a message.
3. From then on, every task runs the full loop:
   • Plan (Fable): decompose, spec each slice, coordinate shared files.
   • Execute (Opus): every code-writing slice is delegated to Opus subagents.
   • Verify (Fable): Fable reviews the full diff against the spec, build + relevant tests actually run, and failures are sent back to Opus with a corrective spec (after 2 failed rounds, Fable fixes directly). Nothing is reported done until verification passes.
4. The two modes are mutually exclusive — /fable-opus on and /fable-opus verify switch between them; /fable-opus off turns everything off.

Verify mode is the most expensive of the two: Fable reviews every slice, not just high-stakes ones. Use build mode when the stakes-based gate is enough.

State is tracked per working directory in ~/.claude/fable-opus/ on your own machine — nothing about your projects is stored in this repo.

Credits

JeredBlu

The heart of this plugin is JeredBlu's work. The following skills are his, included here (with thanks) for convenience:

• prd-creator — conversational PRD discovery
• mcp-evaluator — MCP server security & privacy evaluation
• agent-skill-evaluator — agent skill security & safety evaluation

The frugal-fable skill is also based on his version (itself adapted from BuilderIO's efficient-fable).

• 🔗 Original marketplace: https://github.com/JeredBlu/jeredblu-marketplace
• 🎥 JeredBlu on YouTube — where these tools are shared and explained

Please go support his channel and repos. ❤️

This plugin's additions

On top of JeredBlu's frugal-fable, this repo adds the Fable-plan / Opus-build mode, the full-loop Fable-plan / Opus-build / Fable-verify mode, the /fable-opus toggle command, and the SessionStart re-assert hook — by Eyal Menaker.

If you'd rather get the JeredBlu skills from the original source, install them separately with:

claude plugin marketplace add JeredBlu/jeredblu-marketplace
claude plugin install jeredblu-tools@jeredblu-marketplace

(Do not install both eyal-tools and jeredblu-tools — they'd each provide a frugal-fable skill and collide.)