voicegw.yaml reference

The voicegw.yaml file is the central configuration for VoiceGateway. It is validated at startup using a Pydantic schema with extra="forbid", which means any typo or unknown key produces a clear error message before your gateway starts.

VoiceGateway searches for the config file in this order:

1. ./voicegw.yaml (current directory)
2. ~/.config/voicegateway/voicegw.yaml
3. /etc/voicegateway/voicegw.yaml

You can override this with the VOICEGW_CONFIG environment variable. See Environment variables.

Top-level sections

The config file has ten top-level sections. All are optional.

providers

Configure credentials and settings for each provider. Keys are provider names matching VoiceGateway's built-in provider identifiers.

providers:
  deepgram:
    api_key: ${DEEPGRAM_API_KEY}
  openai:
    api_key: ${OPENAI_API_KEY}
  anthropic:
    api_key: ${ANTHROPIC_API_KEY}
  groq:
    api_key: ${GROQ_API_KEY}
  cartesia:
    api_key: ${CARTESIA_API_KEY}
  elevenlabs:
    api_key: ${ELEVENLABS_API_KEY}
  assemblyai:
    api_key: ${ASSEMBLYAI_API_KEY}
  ollama:
    base_url: http://localhost:11434
  whisper:
    enabled: true
  kokoro:
    enabled: true
  piper:
    enabled: true

Each provider supports at minimum:

• api_key (string): API key, typically via ${ENV_VAR} substitution.
• base_url (string): override the default API endpoint.
• enabled (bool, default true): disable a provider without removing its config.

See Providers for per-provider details.

models

Register custom model aliases organised by modality. Each entry maps an alias to a provider and model name, with optional defaults.

models:
  stt:
    fast-transcription:
      provider: deepgram
      model: nova-3
    offline-transcription:
      provider: whisper
      model: large-v3
  llm:
    reasoning:
      provider: anthropic
      model: claude-sonnet-4-5
  tts:
    narrator:
      provider: cartesia
      model: sonic-3
      default_voice: narrator-male

See Models.

stacks

Named bundles that map to one STT, one LLM, and one TTS model. Use stacks to define preset quality / cost tiers.

stacks:
  premium:
    stt: deepgram/nova-3
    llm: anthropic/claude-sonnet-4-5
    tts: cartesia/sonic-3
  budget:
    stt: groq/whisper-large-v3
    llm: groq/llama-3.3-70b-versatile
    tts: local/piper:en_US-lessac-medium
  local:
    stt: local/whisper-large-v3
    llm: ollama/llama3.2:3b
    tts: local/kokoro

See Stacks.

projects

Define projects for cost attribution and budget enforcement. Each project can override providers per-key.

projects:
  customer-support:
    name: Customer Support Bot
    description: Production support agent
    default_stack: premium
    daily_budget: 50.00
    budget_action: throttle
    tags: [prod, support]
    providers:
      deepgram:
        api_key: ${SUPPORT_DEEPGRAM_KEY}
      anthropic:
        api_key: ${SUPPORT_ANTHROPIC_KEY}
  internal-qa:
    name: Internal QA Bot
    description: Testing and QA agent
    default_stack: budget
    daily_budget: 10.00
    budget_action: warn
    tags: [dev, qa]

default_project: customer-support

budget_action is one of warn, throttle, or block. Project- scoped providers override the top-level providers for that project; otherwise the top-level keys apply.

See Projects.

fallbacks

Ordered lists of model ids per modality. Used as a resolver-time hint: walk the list at startup and pick the first model whose provider plugin imports cleanly.

fallbacks:
  stt:
    - deepgram/nova-3
    - openai/whisper-1
    - local/whisper-large-v3
  llm:
    - anthropic/claude-sonnet-4-5
    - openai/gpt-4.1-mini
    - ollama/llama3.2:3b
  tts:
    - cartesia/sonic-3
    - elevenlabs/eleven_multilingual_v2
    - local/kokoro

observability

Three boolean flags that control which middleware runs. All default to true.

observability:
  latency_tracking: true
  cost_tracking: true
  request_logging: true

See Observability.

cost_tracking

Configure the SQLite storage backend for cost persistence.

cost_tracking:
  enabled: true
  db_path: ~/.config/voicegateway/voicegw.db
  daily_budget_alert: 100.00

• enabled (bool, default false): enable cost persistence. Also enabled automatically if VOICEGW_DB_PATH is set.
• db_path (string): path to the SQLite database file.
• daily_budget_alert (float, optional): global daily budget alert threshold.

latency

Configure latency monitoring thresholds.

latency:
  ttfb_warning_ms: 500.0
  percentiles: [50.0, 95.0, 99.0]

• ttfb_warning_ms (float, default 500.0): time-to-first-byte warning threshold in milliseconds.
• percentiles (list of floats): which percentiles to track and report.

rate_limits

Per-provider rate limiting.

rate_limits:
  deepgram:
    requests_per_minute: 100
  openai:
    requests_per_minute: 60

• requests_per_minute (int): maximum requests per minute for the given provider.

serve

Bind host and port for the daemon. The daemon serves the HTTP API (/v1/*), the dashboard API (/api/*), and the React SPA (/) all on this single port.

serve:
  host: 0.0.0.0
  port: 8080

• host (string, default 0.0.0.0): bind address. Use 127.0.0.1 to restrict to localhost.
• port (int, default 8080): port number. The wizard collects this as question 4 of voicegw onboard.

Environment variable substitution

Any string value in the config can use ${ENV_VAR} syntax. VoiceGateway substitutes these at load time using os.environ.

providers:
  deepgram:
    api_key: ${DEEPGRAM_API_KEY}

If the environment variable is not set, it resolves to an empty string.

See Environment variables.