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 skills add epicsagas/Velith --skill book-gamegit clone --depth 1 https://github.com/epicsagas/VelithWrote 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/epicsagas/velith/book-game)<a href="https://agentmods.dev/skills/epicsagas/velith/book-game"><img src="https://agentmods.dev/badge/skills/epicsagas/velith/book-game.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
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 5.1 | $0.00044 | $0.01028 |
| Opus 5 | $0.00022 | $0.00514 |
| Sonnet 5 | $0.00009 | $0.00206 |
| Haiku 4.5 | $0.00004 | $0.00103 |
Grade A, and why
book-game 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 2d 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.
How it starts
The opening of the file, as written. The whole thing — 75 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Game Narrative
The reader is a player. They act, and the story must answer. A game script that reads well but ignores the player's hands is a screenplay with buttons.
Architecture
- Critical path (60%): must work if the player does nothing optional. Every beat of the main story lands regardless of side content.
- Side content (30%): enriches, never gates. Side quests reward with understanding of the world or characters, not only items.
- Hidden (10%): for players who look. Rewards curiosity.
- Branch depth ≤ 4 before convergence. Convergence types: full (all paths merge), partial (state carries), butterfly (small early choice, large late consequence; use once or twice per game, telegraph nothing).
- Choice types: binary, multi-way, conditional (flag/item), timed. A choice with no consequence is a menu, not a choice. A choice where one option is obviously correct is not a choice.
- Endings: each ending is earned by a pattern of choices, not one final selection. The player should be able to explain why they got their ending.
Quest design
Per quest: ID, title, hook (why the player cares), prerequisites (flags, items, relationships), steps (3-7, each verifiable by the game), branch points, resolution, rewards, flags set. Quest chains: linear, hub, parallel.
The hook is narrative, not "collect five." The reward includes a change in the world the player can see.
Dialogue system
- Node: speaker, line, emotion tag, next-node links, conditions.
- Player responses ≤ 3 per node; each is a stance (investigate, push, withdraw), not a paraphrase of the same thing.
- NPC state (trust, fear, knowledge) affects available lines. Track in the bible.
- Barks and ambient lines carry world texture; write them with the same care as cutscene dialogue.
- Lines are short. Players skip. The most important line in a conversation is the one that changes state, and it should be unmissable.
- Localization: avoid idioms that do not travel; keep string lengths sane for UI.
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.
- 2d ago Changed · +50 lines · +18 tokens per session 3455e0537f5e
- 8d ago First seen · 25 lines · 26 tokens per session scan A 71d436b6ac61
book-game is a skill published in the GitHub repository epicsagas/Velith (33 stars, last pushed 2d ago), licensed Apache-2.0. It adds 44 tokens to every session and 1,028 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 2026-08-30.
Other skills, from other repositories
ai-native-software-dev
Use when the user asks to build, change, modernize, or reconstruct non-trivial software with an AI-native workflow, including greenfield development, work in an existing codebase, or authorized reference-based product reconstruction; also use when lifecycle planning, architecture, implementation, testing, review…
bforge
Build game-ready 3D assets with Blender — props, modular kits, terrain, characters with rigs and animation, materials, LODs, collision, glTF export. Use whenever the task involves making, fixing, inspecting or exporting a 3D model, texture, environment piece or character for a game, or when someone says "make a…
gsp-orchestrator
Use when a request needs routing across this Game Superpowers collection for build, audit, repair, or polish work.
gsp-project-audit
Use when running a top-level audit of an existing game project before repair or major changes.
gsp-spec-driven-planning
Use when the user wants a persistent requirements/spec/design/tasks workflow, asks for OpenSpec-style planning, or needs durable change artifacts in the target repo.
gsp-build-strategy
Use when deciding development mode, quality target, task granularity, or refactor policy for game work.