# Claude Fable 5 Consult

> Use when Codex should ask Claude Fable 5 for a second opinion, strategy review, implementation review, risk review, launch review, or high-stakes reasoning pass through the user's own Claude Code CLI. Provides token-conscious prompt packing, reliable prompt-file invocation, model-name normalization, UTF-8 handling, cost caps, saved outputs, and read-only safety defaults for Fable consultations.

- **Type:** Skill
- **Install:** `agentstack add skill-kei99-web3-codex-claude-fable-5-consult-skill-codex-claude-fable-5-consult-skill`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [kei99-web3](https://agentstack.voostack.com/s/kei99-web3)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [kei99-web3](https://github.com/kei99-web3)
- **Source:** https://github.com/kei99-web3/codex-claude-fable-5-consult-skill

## Install

```sh
agentstack add skill-kei99-web3-codex-claude-fable-5-consult-skill-codex-claude-fable-5-consult-skill
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Claude Fable 5 Consult

Use this skill when a user asks Codex to ask Claude Fable 5, Fable, or another Claude frontier model for a second opinion, review, or recommendation.

## Core Rules

- Use the full model name `claude-fable-5`. Short aliases such as `fable` or `fable-5` may fail in Claude Code CLI.
- Prefer prompt files over direct command arguments. This avoids shell quoting, long prompt, and Japanese/Unicode encoding failures.
- Set a cost cap for every real call with `--max-budget-usd`.
- Use `--no-execute` for smoke tests. Tiny paid Fable calls can still create Claude Code prompt/cache overhead before visible output.
- Use the prompt packer when context is large; Fable should receive a compact decision packet, not an unbounded workspace dump.
- Keep Fable read-only unless the user explicitly asks otherwise. Codex should own file edits, implementation, tests, commits, and final judgment.
- Do not send `.env` files, API keys, tokens, private keys, credentials, or other secrets.
- For production systems, separate `review/recommendation` from `runtime change`; do not change live systems without the user's approval boundary.
- This skill invokes the user's local `claude` CLI and account. It does not use the skill author's API key, subscription, server, or billing.

## Standard Workflow

1. Create a compact UTF-8 prompt file with:
   - objective and decision needed
   - compressed facts, metrics, and relevant file paths
   - safety and approval boundaries
   - exact output format requested
2. Run the bundled script.
3. Read the saved response and let Codex verify it against local evidence.
4. Treat Fable output as a strong external review, not as automatic authority.
5. Implement only recommendations that pass local checks and the user's approval boundary.

## Recommended Invocation

Cross-platform Python:

```bash
python scripts/invoke_fable5_consult.py \
  --prompt-file ./prompt.txt \
  --out-file ./fable_response.json \
  --max-budget-usd 0.75
```

Windows PowerShell wrapper:

```powershell
powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\invoke-fable5-consult.ps1 `
  -PromptFile .\prompt.txt `
  -OutFile .\fable_response.json `
  -MaxBudgetUsd 0.75
```

No-cost preflight:

```bash
python scripts/invoke_fable5_consult.py \
  --prompt-file ./prompt.txt \
  --out-file ./fable_response.json \
  --no-execute
```

File-aware read-only review:

```bash
python scripts/invoke_fable5_consult.py \
  --prompt-file ./prompt.txt \
  --out-file ./fable_response.json \
  --add-dir /path/to/project \
  --allowed-tools Read \
  --max-budget-usd 1.00
```

Prefer compressed-context prompts over broad file access unless Fable truly needs source files.

## Token-Conscious Prompt Pack

When the user asks to save tokens or when the context has multiple files, build a compact prompt first:

```bash
python scripts/build_fable_prompt_pack.py \
  --goal "Review this plan and recommend the next best action." \
  --context-file ./README.md \
  --context-file ./SKILL.md \
  --out-file ./prompt_pack.txt \
  --max-chars-total 12000 \
  --max-chars-per-file 4000
```

Then invoke Fable with `--prompt-file ./prompt_pack.txt`.

The packer strips excess whitespace, caps each file, marks truncation, and blocks obvious secret-like content. Codex still needs to choose the smallest useful file set.

## Prompt Pattern

```text
You are a senior reviewer for [domain].

Objective:
- [decision needed]

Context:
- [compressed facts, metrics, constraints]

Safety/approval boundaries:
- [what must not be changed automatically]

Ask:
- Provide [N] prioritized recommendations.
- For each: goal, why now, implementation/validation, promotion condition, kill condition.
- Name the one action you would choose this week.

Output:
- [language and format]
- Be concrete and falsifiable.
- Do not invent unavailable data.
```

## Failure Handling

- If a model error mentions `fable` or `fable-5`, rerun with `claude-fable-5`.
- If the shell reports missing input, use `--prompt-file` instead of inline prompt arguments.
- If the command returns no visible text, use JSON output and inspect the saved `.json` plus generated `.md` sidecar.
- If `error_max_budget_usd` appears on a tiny prompt, it may be Claude Code prompt/cache overhead. Use `--no-execute` for checks and a realistic budget for actual work.
- If Fable gives a plausible but unverified recommendation, turn it into a local hypothesis and test it before acting.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [kei99-web3](https://github.com/kei99-web3)
- **Source:** [kei99-web3/codex-claude-fable-5-consult-skill](https://github.com/kei99-web3/codex-claude-fable-5-consult-skill)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** yes
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-kei99-web3-codex-claude-fable-5-consult-skill-codex-claude-fable-5-consult-skill
- Seller: https://agentstack.voostack.com/s/kei99-web3
- Browse the marketplace: https://agentstack.voostack.com/browse

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