/audio-direction — Define the Sonic Identity
Overview
Many indie games sound like one sound library used flat: the same generic "swoosh" for menu, jump, pickup and hit. This skill builds an audio bible that names the music style, the SFX vocabulary, the dynamic music plan, and the spatial / mix rules. Writes to .summer/audio-bible.md and configures the audio bus layout in the project so the rest of the work has a real foundation.
Core principle: SFX needs a vocabulary, not a library. Eight named SFX classes with consistent character beat 80 random library hits.
Steps
1. Open with three references
Ask exactly this:
Three reference tracks, games, or films for the music. What instruments matter? And what's the SFX vibe — chunky, clean, synthetic, or organic?
Three is the minimum. One or two collapses into a clone.
If they freeze, offer four axes (not titles):
Pick the closest: a) orchestral + cinematic (Hollow Knight, Journey), b) lo-fi electronic + ambient (Disco Elysium, Outer Wilds), c) chiptune / synth (Hyper Light Drifter, Celeste), d) acoustic / folk (Sable, A Short Hike).
2. Read the brief and art bible if they exist
Read .summer/GameSoul.md Read .summer/art-bible.md
Audio must rhyme with the visuals. Quote it back:
Art bible says "soft, hand-warmed, golden-hour, painterly". That rhymes with acoustic / folk / lo-fi over orchestral or aggressive synth. Confirming.
If the brief says "horror", that constrains the music style harder than the user's references will. Name the constraint.
3. Pin the music style
Force one primary style. Sub-styles can blend, but a primary is required.
| Style | Anchor instruments | Pairs with | Avoid |
|---|---|---|---|
| Orchestral cinematic | Strings, brass, choir | Story-led, fantasy | Casual / cozy |
| Acoustic / folk | Guitar, piano, hand percussion | Cozy, narrative | Action / horror |
| Lo-fi electronic | Vintage synth pad, tape sat, light beat | Atmospheric, indie | Combat-heavy |
| Chiptune / synthwave | 8-bit / 16-bit chips, FM synth | Retro, platformer | Realism |
| Industrial / metal | Distorted bass, percussion-led | Horror, action | Cozy |
| Ambient drone | Pads, no drums, slow movement | Walking sim, horror | Action |
| Jazz / fusion | Live instruments, improv | Stylish, narrative | Generic action |
| Tracker / hyperpop | Glitchy, dense, modern | Esoteric, indie | Mass appeal |
Ask:
One primary style. Which?
4. Define tempo + key range
Concrete numbers, not "varies".
Tempo range: 80–110 BPM (slow side; combat would push 120+) Key center: D minor (warm but melancholic) Modulation rule: combat tracks shift to D dorian, calm tracks to D natural minor Time signature: 4/4 default; 6/8 for emotional cues
5. Build the SFX vocabulary
Eight named classes. Each class has a character, not a single sound.
| Class | Character | Examples in this game | DON'T |
|---|---|---|---|
| UI | Soft, woody, short (60-100ms) | Menu hover, button click, tab switch | No bell tones, no synth blips |
| Pickup positive | Warm, ascending interval (major third), 200-400ms | Coin, key, heal | No pure sine "ding" |
| Pickup neutral | Brief tactile, no melodic component | Note, breadcrumb, lore item | No ascending pitch (reads as reward) |
| Negative / damage | Punchy low-mid, slight detune | Player hit, enemy hit, fall damage | No long reverb tail |
| Movement / footstep | Material-aware (wood / stone / grass) | Walk, run, jump, land | No same sample for all surfaces |
| Attack / action | Front-loaded transient, short body | Swing, parry, dash | No layered orchestral hit |
| Ambient layer | Continuous, low presence | Wind, room tone, distant waves | No looping melody |
| Stinger / event | Distinctive, rare, melodic | Boss intro, level clear, story beat | No reuse for normal events |
Ask:
Eight classes above. Adjust any character / examples / DON'Ts?
6. Define the dynamic music plan
Static music = one track loops forever in a level. Boring. Dynamic music = layers swell with player state. Pick a model.
| Model | How it works | Cost | Best for |
|---|---|---|---|
| Layered stems | One bar / multiple instrument layers; combat adds drum stem, calm removes it | Medium (need stems authored) | Most games |
| Vertical re-orchestration | Same melody, different instrumentation per state | High (composer-led) | Story-led / boss-heavy |
| Horizontal sequencing | Different tracks for different states, crossfade | Low (just author 3-5 full tracks) | Vertical slice scope |
| Procedural / generative | Generate from rules in real-time | High dev cost | Special-case |
Pick one. State the state machine:
States: CALM — exploration, low intensity TENSION — enemies aware but not engaged COMBAT — engaged VICTORY — encounter cleared (4-second sting → return to CALM) Transitions: CALM → TENSION when an enemy detects the player (2s crossfade) TENSION → COMBAT when first damage exchanged (instant drum stem) COMBAT → VICTORY when last enemy dies (drum stem cuts, brass swell) VICTORY → CALM after 4s Rules: No state stays > 90s without variation (loop with bar-1 randomization) Volume ducking: dialogue active → music -6dB Boss music is its own track; ignores normal state machine
7. Define the spatial + mix rules
| Rule | Value |
|---|---|
| 3D attenuation curve | Inverse-square (default), max distance 25m |
| Reverb buses | 1 small (interior), 1 large (cave / hall), 1 outdoor |
| HRTF for player | ON (headphone-friendly directional cues) |
| Master ceiling | -1 dBTP (true peak, no clipping on consoles) |
| Music vs SFX vs UI mix | -8 dB / 0 dB / -3 dB (SFX is loudest) |
| Footstep rolloff | Cuts at 4m for player; cuts at 10m for NPC (player needs them, distant NPCs are noise) |
| Compression | Light bus compression on master (2:1, slow attack, 100ms release) |
8. Configure the audio bus layout
Real audio in Summer Engine needs a bus layout. A new project starts with only the Master bus, so configure the remaining buses now.
Preferred (Summer MCP): Buses are typically in default_bus_layout.tres. Modify project setting:
summer_project_setting(key="audio/buses/default_bus_layout", value="res://audio/default_bus_layout.tres")
Ask the user:
May I create
audio/default_bus_layout.treswith these buses: Master / Music / SFX / UI / Voice / Ambient / Reverb_Small / Reverb_Large / Reverb_Outdoor?
On yes, write the .tres directly via Write (it is the engine's plain-text
resource format):
Write audio/default_bus_layout.tres
Fallback (no MCP): Print the .tres for the user to paste, plus the project.godot line.
9. Save the audio bible
Always write the bible. Path: .summer/audio-bible.md.
markdown# Audio Bible — <Game Name> **References:** <3 specific tracks / games / films> **Style:** <one of the 8 above> **Tempo / key:** 80–110 BPM, D minor, 4/4 ## SFX Vocabulary | Class | Character | Examples | DON'T | |---|---|---|---| | UI | Soft, woody, 60-100ms | hover, click | bell tones | | Pickup positive | Warm major-third, 200-400ms | coin, heal | pure sine | | ... | ... | ... | ... | ## Dynamic Music Plan **Model:** Layered stems **States:** CALM / TENSION / COMBAT / VICTORY **Transitions:** ... **Rules:** ... ## Spatial + Mix - 3D attenuation: inverse-square, 25m - Reverb buses: small / large / outdoor - HRTF: ON - Master ceiling: -1 dBTP - Mix bus: Music -8 dB, SFX 0 dB, UI -3 dB - Footstep rolloff: 4m player / 10m NPC ## Bus Layout Master → Music, SFX (→ Reverb_Small / Large / Outdoor), UI, Voice, Ambient
Ask:
May I create
.summer/audio-bible.mdwith this bible?
10. Optional — generate first SFX seeds
If the user wants to start generating, propose 3-5 SFX seeds aligned with the vocabulary. These are starting points, not finals. Generate them with the sound-effect skill: the first sound effect in a chat starts with its question (three versions from three models, picked by ear in Summer Studio), and its prompt shape is the one that tested well.
assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a fingertip taps a small wooden button, soft woody click, no tail, close-mic, dry, no reverb, no music, no voices.", durationSeconds: 0.5 }) assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a small gold coin drops onto a wooden table, bright metallic ting with a short ring, close-mic, dry, no music, no voices.", durationSeconds: 0.5 }) assets.generate_audio({ capability: "sound_effects", text: "Foley one-shot: a fist hits a padded leather vest, low-mid thump, no tail, close-mic, dry, no reverb, no music, no voices.", durationSeconds: 0.5 })
capability is required; sound_effects reads from text (not prompt), and the length argument is durationSeconds (not duration) with a floor of 0.5 s (1 s for Stable Audio 3 SFX). Leave out modelId so the person's approved default model runs. Ask for the character you want inside the text and let the player only use the front of the clip — you cannot request 80 ms.
Ask first:
May I generate first-pass SFX seeds for UI, pickup, and damage classes? They're starting points, not finals.
11. Route to the next step
End with:
Bible saved. Next:
/design-mechanicto wire SFX cues into specific mechanics./game-feelif you haven't paired audio with visual effect cues yet.- Author or generate the calm music track first; it's the longest-running and sets the room tone.
Common mistakes
| Mistake | Fix |
|---|---|
| Single reference for music | Three minimum. Listen for the common element across them. |
| "Library" instead of "vocabulary" | A bag of free SFX with no shared character feels random. Eight named classes with character notes. |
| Same SFX for all events | If pickup-coin and pickup-key sound identical, the player learns nothing from audio. |
| No dynamic music plan | Static loops bore in 90s. Pick a model (layered / vertical / horizontal / procedural). |
| Music louder than SFX | Players need SFX for gameplay; music is mood. Default mix is -8 dB music vs 0 dB SFX. |
| No reverb buses | "Send" architecture (rooms route to a small/large/outdoor reverb bus) is mandatory or your mix sounds dry-then-wet inconsistently. |
| Pure sine "ding" for pickup | Reads as cheap mobile game. Use a major-third interval with character. |
| Same footstep sample for all surfaces | Players hear footsteps constantly; material-aware steps carry much of the perceived audio quality. |
| No master ceiling / true peak | Audio clips on console builds without -1 dBTP ceiling. Always set it. |
| Assuming SetResourceProperty fails silently on inline sub_resources | It does not — inline targets work, and the structural failures (node not found, property is not a resource, resource is null) are explicit errors. What is silent on current engines is a bad value shape: a JSON object instead of an engine literal string, a misspelled subProperty, or a wrong-typed value returns ok:true yet no-ops or coerces destructively. Pass class names and literal strings, and confirm in the saved .tres/.tscn, never from ok alone. See summer_docs_read id reference/mcp-tools-reference. |
Collaborative protocol
This skill writes one bible (.summer/audio-bible.md), creates a bus layout (audio/default_bus_layout.tres), modifies project.godot, and may generate audio (metered). Always ask before writing or generating. See summer_docs_read id reference/collaborative-protocol.
Want a working starter?
No template — this is a workflow that produces the bible the rest of the project obeys. After the bible exists, the bus layout is set up and any subsequent audio work (footstep system, dynamic music) reads from it.
See also
summer_docs_readidreference/collaborative-protocolsummer_docs_readidreference/godot-version— Summer compatibility and version-sensitive audio API notessummer_docs_readidreference/mcp-tools-referencebrainstorm-game— produces the brief that anchors the bibleart-direction— the visual counterpart; audio must rhyme with itadaptive-music— implements the dynamic music plansound-effect,music-track,ambient-bed,voice-line— generate the audio the bible describes
From a shell
No Summer MCP tools in this session? Run each one as a command; when summer --version is missing or below 4.0, use npx -y summer-engine@latest in place of summer. Fields are flags in kebab-case (--scene-path res://main.tscn) or one --input '<json>', and summer ops describe <op> prints the exact input. The summer-cli skill has the rest.
| In this skill | Command |
|---|---|
summer_assets_generate_audio | summer assets generate-audio |
summer_docs_read | summer docs read |
summer_add_node | summer engine add-node |
summer_get_project_context | summer engine get-project-context |
summer_get_scene_tree | summer engine get-scene-tree |
summer_inspect_node | summer engine inspect-node |
summer_project_setting | summer engine project-setting |
