Show HN: Beckon, distinct sounds for what your AI coding agent needs

Beckon, a new open-source tool by developer Isa1asN, assigns distinct sounds to an AI coding agent's lifecycle events so developers can know whether to look, unblock, wait, or read an error without watching the terminal. The tool, which requires Claude Code, binds to agent hooks and plays different tones for finished turns, blocked decisions, failures, and rate-limiting, with configurable packs and per-project sound variations. It is available via cargo install and on GitHub, with Linux fully verified and macOS/Windows builds tested in CI but audio unverified.

Distinct sounds for your AI coding agent, so you don't have to watch the terminal. beckon binds to your agent's lifecycle hooks and plays a different sound depending on what it needs: | Sound | Meaning | What to do | |---|---|---| | rising chime | finished its turn | go look | | insistent sting | blocked on your decision | go unblock it | | falling tone | it failed | go read the error | | slow pulse | rate-limited or throttled | wait | A single undifferentiated ding tells you something happened. It doesn't tell you whether to get up. cargo install beckon-cli the binary is called beckon beckon init binds the hooks — shows a diff and asks first beckon test hear the active pack Or from source: git clone https://github.com/Isa1asN/beckon && cd beckon && cargo install --path . init prints the exact change it will make to ~/.claude/settings.json , copies the file to settings.json.beckon-backup-<timestamp beside itself, and only then writes. beckon uninstall removes beckon's entries and leaves everything else alone. It refuses to touch a settings file it cannot round-trip: invalid JSON, invalid UTF-8, a non-object root, or an unfamiliar hooks shape. A file it does accept is re-serialised, so non-canonical formatting CRLF, tabs, duplicate keys is normalised. Content is preserved; the backup keeps the original bytes. | Builds | Test suite | Audio verified | | |---|---|---|---| | Linux x86-64 | yes | yes | yes | | macOS | yes | in CI | no | | Windows | yes | in CI | no | CI runs the full suite on all three. CI runners have no sound device, so playback there goes through the null backend — the macOS and Windows audio paths compile and are exercised structurally, but nobody has heard them. Reports welcome. Also built without the embedded-audio feature, which is the shape a fully static musl binary takes: no cpal, no libasound, falling back to a system player. Requires Claude Code. Other agents are planned; the adapter seam exists and is documented in docs/DESIGN.md /Isa1asN/beckon/blob/main/docs/DESIGN.md . beckon test play every sound in the active pack beckon packs list packs beckon use cipher switch pack beckon mute 30m quiet for a while 45s, 2h, … ; unmute ends it beckon doctor why is it quiet? every reason, listed beckon config set volume 0.4 beckon uninstall By default beckon: - says nothing when a turn finished in under 30 seconds — you were still watching - always plays a blocking alert, however fast it arrived, because a permission prompt stalls progress - doesn't repeat the same sound for the same session within 1.5 seconds - stays quiet for a tool failure, since a failing test is normal work beckon config set events.tool-failed true to change that - ignores a tool you interrupted yourself - caps concurrent sounds at 8 If it's quiet and you didn't ask it to be, beckon doctor says why. Each project gets a stable transposition from a consonant scale, so api-server and worktree-auth sound different with the same pack, and two sounding together harmonise rather than clash. Nothing to configure; disable with beckon config set identity.per project false . Rate limiting is scoped per session and per state. A machine-wide throttle would let one agent's completion chime swallow another's permission alert. Three ship inside the binary, all original, all CC0: aurora — calm starship computer. Soft triangle arpeggios, long reverb. cipher — stealth-game alert. Short, dry, cuts through. unit-7 — deadpan lab robot. Mechanical FM bleeps, no reverb. A pack is a TOML file, not a folder of audio. Sounds are synth recipes — oscillators, envelopes, filters — about a kilobyte of text: sounds.done type = "synth" reverb = { room = 0.55, mix = 0.34 } sounds.done.layer wave = "triangle" notes = "C5", "E5", "G5" step ms = 92 filter = { kind = "lowpass", cutoff hz = 3200 } So a pack is provably original, weighs nothing, and can be reviewed as a diff. Auditing a folder of binary blobs for licence provenance is what makes shared sound libraries impractical. To write one, drop a pack.toml in ~/.local/share/beckon/packs/<id / . It shadows a built-in of the same name, so you can fork aurora and keep the name. beckon test <id to hear it. You don't need to author a pack to use your own audio: beckon config set sounds.needs-you ~/sounds/alert.wav Anything you don't override falls through to the active pack, at every step of the fallback chain — replace failed and rate-limited follows it. wav, ogg, flac and mp3 are supported. The path is checked when you set it, so a typo fails immediately rather than becoming silence you notice days later. Or write the table directly: ~/.config/beckon/config.toml sounds needs-you = "~/sounds/alert.wav" done = "~/sounds/ding.wav" sounds is honoured only in your own config, never in a project's .beckon.toml . A repository you clone can change when beckon makes a noise; it cannot name files on your machine and have them opened by a media decoder. Sample files are bounded: regular files only, 10 MiB and 30 seconds maximum, and a pack's samples must resolve inside the pack after symlinks are followed. - No daemon. Nothing runs between hooks. Your agent invokes beckon, it decides in ~5ms, hands playback to a detached child, and exits. - No network at hook time. - No telemetry. - Packs are data, never executed. - Exits 0 unconditionally — bad config, no audio device, corrupt input, panic. beckon binds hooks that block the agent on a non-zero exit, so this is verified against the release binary, where panic = "abort" puts it beyond the reach of cargo test . - Publish to crates.io - Hear it on macOS and Windows CI builds and tests there already - beckon install github:user/repo — packs from git - A browsable community pack index - SSH: escape sequences so a remote agent alerts your local terminal - Adapters for Codex, Cursor, Gemini - npm and Homebrew distribution git clone https://github.com/Isa1asN/beckon && cd beckon ./scripts/install-hooks.sh pre-commit: fmt + clippy ./check.sh --release everything CI enforces main requires a pull request and signed commits . If you don't already sign, GitHub will reject the push without much explanation: git config --global gpg.format ssh git config --global user.signingkey ~/.ssh/id ed25519.pub git config --global commit.gpgsign true Then add the same key to GitHub under Settings → SSH and GPG keys with key type Signing Key — an authentication key does not count, and that catches most people out. CI runs fmt, clippy with -D warnings , the suite on Linux/macOS/Windows, a build with no audio backend, an MSRV check, the release-binary safety script, and crates.io packaging. ./check.sh --release covers everything except the other two platforms. New sound packs are welcome — a pack is a TOML file, so a pull request adding one is reviewable as a diff. Design notes: docs/DESIGN.md /Isa1asN/beckon/blob/main/docs/DESIGN.md . Code is MIT OR Apache-2.0. The built-in packs are CC0-1.0.