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 ouzlifaneyassine1-dot/onyx-engine --skill sound-effectgit clone --depth 1 https://github.com/ouzlifaneyassine1-dot/onyx-engineWrote 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/ouzlifaneyassine1-dot/onyx-engine/sound-effect)<a href="https://agentmods.dev/skills/ouzlifaneyassine1-dot/onyx-engine/sound-effect"><img src="https://agentmods.dev/badge/skills/ouzlifaneyassine1-dot/onyx-engine/sound-effect/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/ouzlifaneyassine1-dot/onyx-engine/sound-effect"><img src="https://agentmods.dev/badge/skills/ouzlifaneyassine1-dot/onyx-engine/sound-effect.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00086 | $0.02853 |
| Opus 5 | $0.00043 | $0.01426 |
| Sonnet 5 | $0.00017 | $0.00571 |
| Haiku 4.5 | $0.00009 | $0.00285 |
Grade A, and why
sound-effect 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 11d 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.
This is a copy
86% identical to sound-effect — 47 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 238 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/sound-effect — Generate a Short SFX One-Shot and Wire It
Overview
This skill produces one named SFX clip aligned with the audio bible's vocabulary, then wires it into the scene as an AudioStreamPlayer that plays once and frees its parent (or stops cleanly if it's a looped texture). The shape of the prompt is what makes the difference between "metal sword swing whoosh, dry, sharp, 250ms" returning the right clip on the first try and "epic battle sound" returning twenty seconds of musical noise.
ElevenLabs SFX (the sound_effects capability of onyx_generate_audio) is literal. It treats the prompt as a description of a real sound, not as a vibe. Concrete material + action + intensity beats adjectives every time.
When to use
- One-shot SFX: footstep, swing, click, hit, impact, pickup, jump, land, door, breath.
- Short loops < 2s: hum, drone snippet, rain texture (for very short looping ambients prefer
audio/ambient-bed). - Replacing a placeholder beep with something on-bible.
When NOT to use
- Music or musical stings →
audio/music-track. - Long location ambience (>5s) →
audio/ambient-bed. - Voice / dialogue →
audio/voice-line. - Defining the vocabulary of SFX — that's
audio/audio-direction. This skill executes against an existing bible.
Steps
1. Read the audio bible
Read .onyx/audio-bible.md
If it doesn't exist, ask:
No audio bible at
.onyx/audio-bible.md. Want to run/audio-directionfirst to define the SFX vocabulary, or shall I just one-shot this with sensible defaults?
The bible defines an SFX class (UI, Pickup positive, Damage, Footstep, Attack, Stinger, Ambient layer, Pickup neutral). Map the user's request to a class. Quote the class's character and DON'Ts back so the prompt obeys them.
2. Search for an existing clip first
Generation is metered. Reuse beats regenerate.
onyx_search_assets(query="<class> <subject>", filter={ kind: "audio" })
If something fits, ask:
Found
audio/sfx/sword_swing_01.wav. Use this, or generate fresh?
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.
- 11d ago First seen · 238 lines · 86 tokens per session scan A 4c0ad2f5a96b
sound-effect is a skill published in the GitHub repository ouzlifaneyassine1-dot/onyx-engine (0 stars, last pushed 3mo ago), licensed MIT. It adds 86 tokens to every session and 2,853 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. It is 86% identical to sound-effect, differing in 47 lines, and is treated as a copy.
Other skills, from other repositories
metasounds
Create and modify MetaSound Source assets — add/connect nodes, wire pins, set input defaults, and play procedurally (MetaSoundService). Use when the user asks to create a MetaSound, build or edit a MetaSound graph, add operator/input/output nodes, or generate procedural audio.
adaptive-music
Use when wiring music stems to game state — combat / explore / boss / tension crossfades on a shared bus. Pairs generated stems with a state machine and AudioBus structure. Trigger on "adaptive music", "dynamic music", "music changes when combat starts", "layered music", "vertical music", "wire stems".
voice-line
Use when generating TTS voice lines — NPC barks, narrator, dialogue. Covers where voice ids come from, a character-to-voice decision tree, stability/style/similarity guidance, and the multi-line dialogue case via texttodialogue. Trigger on "make a voice line", "narrator", "NPC says", "voice for the merchant", "TTS…
ambient-bed
Use when generating a long looping location ambience — forest at dawn, dungeon air, city street, spaceship hum, cave drip. Non-melodic, low-energy, never draws attention. Wires as a looping AudioStreamPlayer on the Ambient bus with a marked seamless loop. Trigger on "ambient bed", "room tone", "background ambience"…
audio-direction
Use when defining the sonic identity — music style, instruments, SFX vocabulary, dynamic music plan. Outputs an audio bible at .summer/audio-bible.md. Trigger on "audio direction", "audio bible", "music style", "sound design", "what should it sound like", "dynamic music".
music-track
Use when generating a looped or cinematic music track. Loops are authored at >=30s with a marked loop point; cinematic tracks at >=60s linear. Trigger on "generate music", "make a calm track", "boss music", "title screen music", "main theme", "exploration loop", "combat track".