cc-bgm

cc-bgm

Game-style background music & sound effects for Claude Code, reacting to what your coding agent is doing. Fantasy-RPG vibe: a calm village theme while you're idle, adventure music when Claude starts working, a quest-clear chime when it finishes. Windows-first.

Think of a coding session as a quest. You give Claude an order → the adventure music kicks in → tools run → "quest complete!" when the turn ends.

How it works

Claude Code fires hooks on events (session start, tool use, turn end, errors, permission prompts). cc-bgm installs tiny async hooks that call cc-bgm event, a thin Node dispatcher. It reads the hook JSON, decides what should play, and tells a background PowerShell audio daemon (WPF MediaPlayer) to crossfade BGM or fire a sound effect.

Claude Code hook ──> cc-bgm event ──> .cmd file ──> daemon.ps1 ──> 🔊
   (async, stdin JSON)   (thin CLI)   (watched folder)  (WPF, looping)

Key design points:

• BGM only switches on state transitions. Hooks fire on every tool call, but the dispatcher sends idempotent ensure <mode> commands and the daemon no-ops if it's already in that mode — so music never restarts mid-loop.
• SFX are restrained — only meaningful moments (quest clear, error, file save, permission request), with a per-sound cooldown to avoid bursts.
• Non-blocking. Every hook is async:true; Claude never waits on audio. If cc-bgm is missing or slow, your session is unaffected.
• Safe install. cc-bgm init only ever touches the hooks key in settings.json, backs it up first, tags its entries, and uninstall removes exactly those — your permissions and everything else are untouched.

Requirements

• Windows 10/11 (Phase 1 is Windows-only; installs inertly elsewhere)
• Windows PowerShell 5.1 (built in) — not PowerShell 7 (pwsh); WPF audio needs the .NET Framework runtime
• Node 18+

Install

Option A: npm

npm install -g cc-bgm
cc-bgm doctor     # verify the audio stack
cc-bgm init       # install the hooks into ~/.claude/settings.json

Start a new Claude Code session and code as usual.

Option B: GitHub Release (no npm publish required)

1. Download and extract the release zip.
2. Open PowerShell in the extracted folder.
3. Run:

.\install.ps1
cc-bgm doctor
cc-bgm init --abs

install.ps1 copies the package into %LOCALAPPDATA%\Programs\cc-bgm\, creates a cc-bgm.cmd shim, and adds that bin directory to your user PATH. --abs is recommended here so Claude hooks call the installed script by absolute path even if a future shell session does not pick up your PATH immediately.

To remove the release-based install later:

.\uninstall.ps1

Add -PurgeData if you also want to delete %LOCALAPPDATA%\cc-bgm\.

Commands

Command	What it does
cc-bgm init [--dry-run] [--abs]	Install hooks (backs up settings first)
cc-bgm uninstall [--purge]	Remove hooks (--purge also deletes the data dir)
cc-bgm doctor	Check Node / PowerShell / WPF / assets / hooks
cc-bgm status [--json]	Show enabled/volume/daemon/current mode
cc-bgm play <track>	Manually play village, quest, dungeon, credits
cc-bgm stop	Stop BGM
cc-bgm sfx <name>	Fire questclear, error, save, summon, fanfare_soft
cc-bgm volume <0-100>	Set master volume
cc-bgm off / cc-bgm on	Silence / re-enable without uninstalling
cc-bgm config list	Show all options and their values
cc-bgm config set <key> <val>	Change an option (validated, applied live)
cc-bgm config get <key>	Print one option
cc-bgm config reset [<key>]	Reset one option, or all, to defaults
cc-bgm fetch [pack]	Download a CC0 audio pack (default: starter)

To mute for one shell only: set CC_BGM_DISABLE=1.

Adjusting options

After install, all options live in %LOCALAPPDATA%\cc-bgm\config.json. The package code itself is read-only (and replaced on npm update), so nothing you change there is ever lost. The easiest way to change options is the CLI:

cc-bgm config list                 # see everything
cc-bgm config set crossfade 2500   # slower BGM transitions
cc-bgm config set duckLevel 0.2    # duck BGM more under SFX
cc-bgm config set volume 50
cc-bgm config reset                # back to defaults

Changes are validated and applied to the running daemon immediately. Options: volume, crossfade, duckLevel, battleIdleMs (auto work→idle delay), idleTimeoutMs (daemon self-shutdown), logLevel, plus enabled/mute.

Getting real music

The bundled audio is placeholder tones. Pull a real CC0 pack:

cc-bgm fetch starter   # Kenney CC0 jingles (BGM) + interface sounds (SFX)
cc-bgm fetch fantasy   # longer fantasy BGM only; keeps your current/default SFX
cc-bgm play quest      # hear it

Downloads land in %LOCALAPPDATA%\cc-bgm\assets\ and override the placeholders. Or drop your own files there by name — see below.

starter is the quick all-in-one pack. fantasy is a BGM-only override built from longer OpenGameArt CC0 tracks for village, quest, and dungeon, so you can layer it on top of starter if you want real music without changing SFX.

Trigger map (default)

Claude Code event	BGM	SFX
SessionStart	village	fanfare_soft
UserPromptSubmit	quest	—
PreToolUse (Bash/Edit/Write/mcp)	quest	—
PreToolUse (Read)	—	—
PostToolUse (Edit/Write)	—	save
PostToolUseFailure	—	error
Notification (permission)	—	summon
Notification (idle)	village	—
Stop	village	questclear
SessionEnd	stop	—

Edit %LOCALAPPDATA%\cc-bgm\triggermap.json to customize (created on init). Changes take effect on the next session — no need to re-run init.

Replacing the music

The bundled audio is placeholder sine tones — replace them. Drop your own files into %LOCALAPPDATA%\cc-bgm\assets\bgm\ and ...\sfx\ using the same names (village.mp3, quest.ogg, questclear.wav, …). Any of .ogg .mp3 .wav .m4a .flac works, and user files override the bundled defaults.

See assets/CREDITS.md for licensing and where to find CC0 fantasy-RPG music. Do not bundle copyrighted game audio.

Files & data

• Package (read-only at runtime): bin/, daemon/cc-bgm-daemon.ps1, assets/, config/triggermap.default.json
• User data (writable): %LOCALAPPDATA%\cc-bgm\ — config, command channel, asset overrides, logs (logs\daemon-*.log), daemon state

Troubleshooting

• cc-bgm doctor is the first stop.
• Set CC_BGM_DEBUG=1 before an action to capture the daemon's startup stderr to %LOCALAPPDATA%\cc-bgm\logs\spawn-stderr.txt.
• Daemon logs: %LOCALAPPDATA%\cc-bgm\logs\daemon-YYYYMMDD.log.
• The daemon shuts itself down after 30 min idle, and on SessionEnd.

License

MIT