The Speech Pipeline
STT — Speech-to-Text
The STT stage is the entry point of the Agent’s pipeline. It listens to the user’s voice and converts it into text that the Agent can process. The platform and model you choose here directly affects how accurately the Agent understands the user, how quickly it responds, and which languages it can handle.Deepgram
Deepgram is a real-time speech recognition platform built for low-latency, high-accuracy transcription. It is well suited for voice agents that need fast, reliable transcription across a wide range of languages and audio conditions.ElevenLabs Scribe
ElevenLabs Scribe is ElevenLabs’ real-time speech recognition model. It is optimized for live streaming, interactive AI agents, and any use case requiring near-instant transcription.AssemblyAI
AssemblyAI is a speech recognition platform with a focus on accuracy and broad language coverage. It is a good alternative when wider language support or different accuracy characteristics are needed.A note on short utterances
STT engines use a Voice Activity Detector (VAD) to determine when you have finished speaking. The engine listens for a silence gap after your voice, and only once that gap is detected does it finalize the transcription and pass it to the Agent. When you say a single short word, the engine may not detect a clean silence gap quickly — especially if there is background noise — so the response can feel delayed. Speaking in short phrases produces faster, more reliable results.General interaction
Instead of saying a single word and waiting, speak a short, complete phrase:Wake word
The same applies when using a wake word. Saying the wake word alone and pausing can cause a slow response because the engine waits for more audio to confirm the utterance is complete. Pair the wake word with a short phrase to help the engine finalize faster.
See Wake Word and Sleep Interaction for more on how this affects the wake word flow.
Music mode
In music mode, background audio fills the silence the VAD is listening for, making single-word commands harder to detect. If you say just “stop” or “pause” while music is playing, the engine may not cleanly finalize the transcription before more audio arrives. Add a word before or after the command to form a short phrase:TTT — Text-to-Text
The TTT stage is the Agent’s brain. Once the user’s speech has been transcribed by the STT module, the transcribed text is passed to a language model which generates the Agent’s response. The platform and model you choose here directly shapes how intelligently the Agent responds, how well it understands context, and how quickly it replies.OpenAI
OpenAI provides direct access to the GPT model family. Models are accessed using your own OpenAI API key.OpenRouter
OpenRouter is a unified API gateway that provides access to models from multiple AI providers through a single API key. It lets you switch between providers and models without managing separate keys for each.LLM fine-tuning parameters
These parameters apply to the selected TTT model and affect how the Agent generates responses.TTS — Text-to-Speech
The TTS stage is the Agent’s voice. Once the language model has generated a response, the TTS module converts that text into spoken audio. The platform and model you choose here affects how natural the Agent sounds, how quickly it starts speaking, and which languages it can speak in.ElevenLabs
ElevenLabs is a voice synthesis platform offering high-quality, natural-sounding speech with support for voice cloning and a wide range of languages. Models are accessed using your own ElevenLabs API key.Voice fine-tuning parameters
Per-Agent Voice Configuration
The global configuration in Settings → Configuration applies to all Agents. When you need a specific Agent to use a different voice or pipeline, configure it individually in Pro Creation mode. When creating or editing an Agent in Pro Creation, configure voice under Personality Identity:- Voice Identity: Select from the available voices or enter a custom Voice ID from your TTS provider.
- Clone Voice: Use voice cloning to create a personalized voice.
- Preview: Play back the selected voice before saving.


Adding a Custom Voice
To add a custom voice from your TTS provider:- Go to the Agents dashboard and click the
button at the top right. - Fill in:
- Name: Identifies the voice in your list.
- Description: Tone, accent, or intended use.
- Voice ID: The Voice ID from your TTS provider (e.g., ElevenLabs).
- Click
to add the voice, or
to discard.

Getting a Voice ID
Before adding a voice in OpenHome, upload your custom voice to your preferred TTS provider (e.g., ElevenLabs). Once uploaded, you will receive a Voice ID to enter in the field above.Other Configuration Options
API Keys for Providers
Each provider requires an API key. Manage these under Settings → API Keys.When you update API keys, your Agents consume credits from the associated services. OpenHome is not responsible for charges from third-party providers.See Dashboard for full API key management details.
See also
- Configuring Your Agent — conversation controls, identity, and behavior prompts
- Wake Word and Sleep Interaction — how the wake word interacts with STT and the short-utterance pattern
- SDK Reference — OpenRouter model table for use inside Abilities

