kpab/claude-fable-5-skills

# GitHub Repository: kpab/claude-fable-5-skills

**URL:** https://github.com/kpab/claude-fable-5-skills
**Author:** kpab
**Description:** 10 Fable 5-native agent skills — Works with Claude Code, Cursor, Copilot
**Homepage:** 
**Language:** 

## Stats
- Stars: 17
- Forks: 3
- Open Issues: 0
- Commits: 37
- Created: 2026-06-11T07:13:28Z
- Updated: 2026-09-03T01:43:03Z
- Pushed: 2026-09-02T04:37:17Z

## README
# claude-fable-5-skills

**10 battle-ready Agent Skills for Claude Fable 5 and 5.1** — the first skill collection designed around how Claude Fable 5 actually behaves, not how older models needed to be babysat.

[日本語版 README はこちら →](README.ja.md)

> Anthropic's own guidance for Fable 5 notes that skills written for prior models are often too prescriptive for it and can *degrade* output quality. Old skills micromanage; Fable 5 needs intent, boundaries, and verification hooks instead. Every skill here is written Fable 5-first.

Works with **Claude Code, Claude Cowork, Cursor, Copilot, Gemini CLI**, and any harness that reads `SKILL.md` files (agentskills.io-style: YAML frontmatter + Markdown body).

## The 10 skills

| # | Skill | What it fixes |
|---|-------|---------------|
| 1 | [`skill-refactorer`](skills/skill-refactorer/SKILL.md) | **The meta-skill.** Audits your pre-Fable-5 skills/prompts (and Fable 5 skills now running on 5.1), deletes capability-compensation scaffolding, keeps real guardrails. |
| 2 | [`act-when-ready`](skills/act-when-ready/SKILL.md) | Over-planning at high effort: re-deriving settled facts, surveying options it won't pursue. |
| 3 | [`effort-calibrator`](skills/effort-calibrator/SKILL.md) | Picking the right `effort` level per workload; Fable 5 at lower effort often beats older models at `xhigh`, and 5.1 needs its own sweep plus per-message effort changes. |
| 4 | [`no-gold-plating`](skills/no-gold-plating/SKILL.md) | Diffs bigger than the ask: unrequested refactors, speculative abstractions, impossible-state error handling, and (on 5.1) test files out of proportion to the change — Anthropic reports the scoping instruction cuts extras substantially with no change in task success. |
| 5 | [`grounded-progress`](skills/grounded-progress/SKILL.md) | Status reports on long runs must point at tool-result evidence — no more "tests passing" that never ran. Includes the harness setting that makes 5.1 progress updates visible. |
| 6 | [`scope-guard`](skills/scope-guard/SKILL.md) | "Diagnose" ≠ "fix". No unrequested actions, no state changes on pattern-matched evidence. |
| 7 | [`subagent-orchestration`](skills/subagent-orchestration/SKILL.md) | Parallel delegation, long-lived workers, fresh-context verifier subagents that out-perform self-critique, and the per-turn nudge that keeps 5.1 batching tool calls. |
| 8 | [`markdown-memory`](skills/markdown-memory/SKILL.md) | A file-based lesson memory Fable 5 exploits unusually well — with the maintenance discipline that keeps it useful. |
| 9 | [`autonomous-continuation`](skills/autonomous-continuation/SKILL.md) | Unattended runs that stall on "I'll now run X" or mid-run permission questions, or quietly shrink a partly blocked task. Includes the context-budget composure pattern. |
| 10 | [`regrounding-summary`](skills/regrounding-summary/SKILL.md) | Final reports readable by someone who saw none of the work — no arrow chains, no invented abbreviations, no unmarked quotations, no dense unbroken paragraphs. |

## Install

**Claude Code (recommended)** — install as a plugin, get updates automatically:

```
/plugin marketplace add kpab/claude-fable-5-skills
/plugin install fable5-skills@claude-fable-5-skills
```

**Manual** — copy any skill folder into your skills directory:

```bash
git clone https://github.com/kpab/claude-fable-5-skills
cp -r claude-fable-5-skills/skills/act-when-ready ~/.claude/skills/
```

Or cherry-pick per project by placing folders under `.claude/skills/` in the repo. Other harnesses: point your skill loader at the `skills/` directory; each skill is a self-contained folder with one `SKILL.md`.

## How the skills activate

Four skills are task-shaped and trigger automatically when a matching request appears: `skill-refactorer`, `effort-calibrator`, `subagent-orchestration`, `markdown-memory`.

The other six are standing behavioral rules. A model that is mid-over-planning won't reliably decide to invoke `act-when-ready` on its own, so don't count on auto-triggering for these. Two reliable paths:

- **Interactive sessions** — invoke explicitly (e.g. `/act-when-ready`) at the start of the session, or the moment the symptom shows up.
- **Unattended pipelines and always-on use** — copy the skill body into your system prompt or `CLAUDE.md`; this is how Anthropic's own Fable 5 guide ships these patterns. `autonomous-continuation` is written for exactly this.

## Design principles

1. **Intent over procedure.** Fable 5 follows instructions strictly; we state outcomes and boundaries, not step-by-step recipes.
2. **Short by construction.** Every skill fits on one screen. If a line doesn't change behavior, it's deleted.
3. **Verification hooks, not vibes.** Where correctness matters, the skill defines a *check* (evidence rule, turn-ending check, diff self-check), not an exhortation to "be careful".
4. **Original text.** Patterns are informed by Anthropic's public [Prompting Claude Fable 5](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-fable-5) and [Prompting Claude Fable 5.1](https://platform.claude.com/docs/en/build-with-claude/prompt-engineering/prompting-claude-fable-5-1) guides and our own testing; all instruction text here is written from scratch.

## Status & disclaimer

Fable 5 shipped on **2026-06-09**; Fable 5.1 shipped on **2026-09-01** and is now the current Fable, with Fable 5 listed as a legacy model. Anthropic states that existing Fable 5 prompts perform well on 5.1 without changes, and documents a handful of behavior differences; these skills fold those in (effort sweeps, test bloat, fewer progress updates, denser prose, one-call-per-turn loops). Expect further refinements as the community learns the model. Issues and PRs with reproducible before/after examples are very welcome.

This is an unofficial community project, not affiliated with or endorsed by Anthropic. Verify current API parameters against the [official docs](https://platform.claude.com/docs) before production use. Fable 5.1 also carries API-level breaking changes outside the scope of these skills — forced `tool_choice` (`any` / `tool`) returns a 400, earlier models cannot read 5.1 thinking blocks, and editing earlier turns invalidates later thinking blocks — see [What's new in Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1).

## License

MIT — see [LICENSE](LICENSE).