One-liner TTS that works like say: stream to speakers by default, list voices, or save audio files.

Homebrew (macOS):

brew install steipete/tap/sag  # auto-taps steipete/tap

Go toolchain:

go install ./cmd/sag

Requires Go 1.22+.

• ELEVENLABS_API_KEY (required)
• Optional defaults: ELEVENLABS_VOICE_ID or SAG_VOICE_ID

Features:

• macOS say-style default: sag "Hello" routes to speak automatically.
• Streaming playback to speakers with optional file output.
• Voice discovery via sag voices and -v ?.
• Speed/rate controls, latency tiers, and format inference from output extension.
• Model selection via --model-id (defaults to eleven_v3; use eleven_multilingual_v2 for a stable baseline).

Speak (streams audio):

sag speak -v Roger "Hello world"

Call it like macOS say: omitting the subcommand pipes text to speak by default.

sag "Hello world"

macOS say compatibility shortcuts (subcommand optional):

sag -v Roger -r 200 "Faster speech"
sag -o out.mp3 "Save to file"
sag -v ?      # list voices

More examples:

echo "piped input" | sag speak -v Roger
sag speak -v Roger --stream --latency-tier 3 "Faster start"
sag speak -v Roger --speed 1.2 "Talk a bit faster"
sag speak -v Roger --model-id eleven_multilingual_v2 "Use stable v2 baseline"
sag speak -v Roger --output out.wav --format pcm_44100 "Wave output"

Key flags (subset):

• -v, --voice voice name or ID (? to list)
• -r, --rate words per minute (maps to ElevenLabs speed; default 175)
• -f, --input-file read text from file (- for stdin)
• -o, --output write audio file; format inferred by extension (.wav -> PCM, .mp3 -> MP3)
• --speed explicit speed multiplier (0.5–2.0)
• --stability v3: 0|0.5|1 (Creative/Natural/Robust); v2/v2.5: 0..1 (higher = more consistent, less expressive)
• --similarity / --similarity-boost 0..1 (higher = closer to the reference voice)
• --style 0..1 (higher = more stylized delivery; model/voice dependent)
• --speaker-boost / --no-speaker-boost toggle clarity boost (model dependent)
• --seed 0..4294967295 best-effort repeatability across runs
• --normalize auto|on|off numbers/units/URLs normalization (when set)
• --lang en|de|fr|... 2-letter ISO 639-1 language code (when set)
• --stream/--no-stream stream while generating (default on)
• --latency-tier 0–4 lower latency tiers
• --play/--no-play control speaker playback
• --metrics print basic stats to stderr

Voices:

sag voices --search english --limit 20

Run:

sag prompting

Highlights:

• v2/v2.5: SSML pauses via <break time="1.5s" /> (v3 does not support SSML breaks).
• v3: use audio tags like [whispers] and pause tags like [short pause].
• Use the voice knobs: --stability, --similarity, --style, --speaker-boost, plus request controls --seed, --normalize, --lang.

sag supports any ElevenLabs model_id via --model-id (we pass it through). Practical defaults + common IDs:

Notes:

• SSML <break> works on v2/v2.5, not v3. Use pause tags on v3 instead.
• Input limits differ by engine (v3: 5,000 chars; v2: 10,000 chars; v2.5 Turbo/Flash: 40,000 chars). If you hit limits, chunk text and stitch audio.
• --normalize on may not be available for v2.5 Turbo/Flash (higher latency); prefer auto/off if it errors.
• Source of truth: ElevenLabs “Models” docs.

• With pnpm:
  • pnpm format
  • pnpm lint
  • pnpm test
  • pnpm build
  • pnpm sag -- --help (passes args to the Go binary)
• Direct Go:
  • Format: go fmt ./...
  • Lint: golangci-lint run
  • Tests: go test ./...
  • Build: go build ./cmd/sag

• ElevenLabs account and API key required.
• Voice defaults to first available if not provided.
• Non-mac platforms: playback still works via go-mp3 + oto, but device selection flags are no-ops.