deepslate-core 0.1.8

Shared core library for Deepslate SDK integrations

deepslate-core

Shared core library for Deepslate's realtime voice AI SDKs.

You probably don't need to install this directly.

Install deepslate-livekit or deepslate-pipecat instead — they pull in deepslate-core automatically. This package is for developers building custom Deepslate integrations outside of LiveKit or Pipecat.

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What's Inside

deepslate-core provides everything needed to connect to the Deepslate Realtime API from any async Python application:

• DeepslateSession — High-level session that manages the full WebSocket lifecycle, protobuf framing, session initialization, reconnection, and callback dispatch. The primary building block for custom integrations.
• DeepslateOptions — API credentials and connection configuration
• VadConfig — Server-side Voice Activity Detection parameters
• HostedTtsConfig / HostedTtsMode — Deepslate-hosted (cloned) voice TTS configuration
• ElevenLabsTtsConfig / ElevenLabsLocation — ElevenLabs TTS configuration
• BaseDeepslateClient — Low-level async WebSocket client with exponential-backoff reconnection (used internally by DeepslateSession)
• Protobuf definitions — Compiled .proto bindings for the Deepslate realtime wire protocol

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Installation

pip install deepslate-core

Requirements

• Python 3.11 or higher

Dependencies

• aiohttp>=3.10.0 — Async HTTP and WebSocket client
• protobuf>=5.26.0 — Protocol buffer serialization

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Usage

This section is for custom integration authors. For standard usage see the LiveKit or Pipecat packages.

Credentials

from deepslate.core import DeepslateOptions

# Load from environment variables (recommended)
opts = DeepslateOptions.from_env()

# Or configure manually
opts = DeepslateOptions(
    vendor_id="your_vendor_id",
    organization_id="your_org_id",
    api_key="your_api_key",
    system_prompt="You are a helpful assistant.",
)

Required environment variables:

DEEPSLATE_VENDOR_ID=your_vendor_id
DEEPSLATE_ORGANIZATION_ID=your_organization_id
DEEPSLATE_API_KEY=your_api_key

VAD Configuration

from deepslate.core import VadConfig

vad = VadConfig(
    confidence_threshold=0.5,   # 0.0–1.0
    min_volume=0.01,            # 0.0–1.0
    start_duration_ms=200,
    stop_duration_ms=500,
    backbuffer_duration_ms=1000,
)

TTS Configuration

Two TTS providers are supported. Pass either config as tts_config to DeepslateSession.create().

Deepslate-hosted (cloned) voice

Use a voice that has been cloned and hosted within Deepslate. No external provider credentials required.

from deepslate.core import HostedTtsConfig, HostedTtsMode

tts = HostedTtsConfig(voice_id="c3dfa73f-a1ab-4aad-b48a-0e9b9fe4a69f")

# Explicit mode selection
tts = HostedTtsConfig(
    voice_id="c3dfa73f-a1ab-4aad-b48a-0e9b9fe4a69f",
    mode=HostedTtsMode.HIGH_QUALITY,  # or HostedTtsMode.LOW_LATENCY
)

Parameter	Type	Default	Description
voice_id	str	required	ID of the hosted (cloned) voice to use
mode	HostedTtsMode	HostedTtsMode.HIGH_QUALITY	Quality/latency tradeoff for highest response speed

HostedTtsMode values:

Value	Description
HIGH_QUALITY	Best output quality with still relatively low latency. Recommended for most use cases (default).
LOW_LATENCY	Low latency generation mode that takes next to no time to complete. Output quality may be significantly reduced.

ElevenLabs

from deepslate.core import ElevenLabsTtsConfig, ElevenLabsLocation

# Load from environment variables
tts = ElevenLabsTtsConfig.from_env()

# Or configure manually
tts = ElevenLabsTtsConfig(
    api_key="your_elevenlabs_key",
    voice_id="21m00Tcm4TlvDq8ikWAM",
    model_id="eleven_turbo_v2",
    location=ElevenLabsLocation.US,  # US (default), EU, or INDIA
)

DeepslateSession

DeepslateSession is the recommended entry point for custom integrations. It handles the full protocol lifecycle — session initialization, protobuf serialization, reconnection, and server-event routing — delivering events to a DeepslateSessionListener so your code only deals with application logic.

Subclass DeepslateSessionListener and override only the methods you care about, then pass the instance to DeepslateSession.create(). Use create() when your code owns the connection — it creates its own BaseDeepslateClient and closes it automatically when close() is called:

import asyncio
from deepslate.core import (
    DeepslateOptions,
    DeepslateSession,
    DeepslateSessionListener,
    ElevenLabsTtsConfig,
)

class MyListener(DeepslateSessionListener):
    def __init__(self) -> None:
        self.session: DeepslateSession | None = None

    async def on_session_initialized(self) -> None:
        # Session is ready — safe to send the first message
        if self.session:
            await self.session.send_text("What is the capital of France?")

    async def on_text_fragment(self, text: str) -> None:
        print(text, end="", flush=True)

    async def on_audio_chunk(
        self, pcm_bytes: bytes, sample_rate: int, channels: int, transcript: str | None
    ) -> None:
        # Forward PCM audio to your output device / transport
        ...

    async def on_tool_call(self, call_id: str, name: str, params: dict) -> None:
        result = await dispatch_tool(name, params)
        if self.session:
            await self.session.send_tool_response(call_id, result)

    async def on_error(self, category: str, message: str, trace_id: str | None) -> None:
        print(f"[{category}] {message}")

    async def on_response_begin(self) -> None:
        print("\n--- response start ---")

    async def on_response_end(self) -> None:
        print("--- response end ---\n")


async def main():
    opts = DeepslateOptions.from_env(
        system_prompt="You are a helpful assistant."
    )
    tts = ElevenLabsTtsConfig.from_env()
    listener = MyListener()

    session = DeepslateSession.create(
        opts,
        tts_config=tts,
        user_agent="MyApp/1.0",
        listener=listener,
    )
    listener.session = session
    session.start()

    # Initialize for text-only interaction (audio sessions initialize automatically).
    # on_session_initialized will be called once the session is ready.
    await session.initialize(sample_rate=24000, channels=1)

    await asyncio.sleep(5)  # Wait for response
    await session.close()


asyncio.run(main())

Sending audio

Audio sessions initialize automatically on the first send_audio() call. The session also sends a ReconfigureSessionRequest transparently if the audio format changes mid-session:

# pcm_bytes: raw signed 16-bit PCM
await session.send_audio(pcm_bytes, sample_rate=16000, channels=1)

Updating tools at runtime

tools = [
    {
        "type": "function",
        "function": {
            "name": "get_weather",
            "description": "Get the weather for a city.",
            "parameters": {
                "type": "object",
                "properties": {
                    "city": {"type": "string"}
                },
                "required": ["city"],
            },
        },
    }
]

await session.update_tools(tools)

Tool definitions are re-synced automatically after every reconnect.

Reconnection

start() drives BaseDeepslateClient.run_with_retry() internally. On a dropped connection the session resets its state, re-sends InitializeSessionRequest, re-syncs tool definitions, and resumes — all without any action required from your code. Call close() to stop the retry loop permanently.

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API Reference

DeepslateSession.create()

Factory that creates a session together with its own BaseDeepslateClient. The session owns the client and closes it when close() is called.

Parameter	Type	Default	Description
options	DeepslateOptions	required	API credentials and settings
vad_config	VadConfig | None	None	VAD settings (uses defaults if omitted)
tts_config	ElevenLabsTtsConfig | HostedTtsConfig | None	None	Enables server-side TTS audio output
user_agent	str	"DeepslateCore"	HTTP User-Agent header sent on connect
http_session	aiohttp.ClientSession | None	None	Shared aiohttp session (not closed by the session)
listener	DeepslateSessionListener | None	None	Receives all session events; defaults to a no-op base instance

DeepslateSession — send methods

Method	Description
await session.send_audio(pcm, sr, ch)	Send PCM audio; auto-initializes and auto-reconfigures on format change
await session.send_text(text, trigger=IMMEDIATE)	Send a text UserInput
await session.initialize(sr=24000, ch=1)	Explicitly initialize (for text-only sessions)
await session.trigger_inference(instructions=None)	Manually trigger a model reply
await session.send_tool_response(call_id, result)	Return a tool result to the server
await session.update_tools(tools)	Sync tool definitions (persisted across reconnects)
await session.reconfigure(system_prompt=None, temperature=None)	Live-update inference settings
await session.send_direct_speech(text, include_in_history=True)	Speak text directly via TTS, bypassing the LLM
await session.export_chat_history(await_pending=False)	Request a history export; result delivered via on_chat_history
await session.send_conversation_query(query_id, prompt, instructions)	Side-channel inference; at least one of prompt/instructions required; result via on_conversation_query_result
await session.report_playback_position(bytes_played)	Report audio playback position for server-side truncation

DeepslateSessionListener

Subclass this and override only the methods you need. All methods are async and default to no-ops.

Method	Signature	Called when
on_session_initialized	()	Session is fully initialized and ready to accept messages
on_text_fragment	(text: str)	Model streams a text token
on_audio_chunk	(pcm_bytes: bytes, sample_rate: int, channels: int, transcript: str | None)	Model streams a TTS audio chunk
on_tool_call	(call_id: str, name: str, params: dict)	Model requests a tool invocation
on_response_begin	()	Model response starts
on_response_end	()	Model response ends
on_user_transcription	(text: str, language: str | None, turn_id: int)	User speech transcription result arrives
on_playback_buffer_clear	()	Server cleared its audio playback buffer
on_chat_history	(messages: list[ChatMessageDict])	Chat history export received
on_conversation_query_result	(query_id: str, text: str)	Side-channel query result received
on_error	(category: str, message: str, trace_id: str | None)	Server sent an error notification
on_fatal_error	(e: Exception)	All reconnect retries exhausted

DeepslateOptions

Parameter	Type	Default	Description
vendor_id	str	env: DEEPSLATE_VENDOR_ID	Deepslate vendor ID
organization_id	str	env: DEEPSLATE_ORGANIZATION_ID	Deepslate organization ID
api_key	str	env: DEEPSLATE_API_KEY	Deepslate API key
base_url	str	"https://app.deepslate.eu"	Base URL for Deepslate API
system_prompt	str	"You are a helpful assistant."	Default system prompt
ws_url	str | None	None	Direct WebSocket URL (overrides base_url; for local dev)
max_retries	int	3	Maximum reconnection attempts before giving up

VadConfig

Parameter	Type	Default	Description
confidence_threshold	float	0.5	Minimum confidence to classify audio as speech (0–1)
min_volume	float	0.01	Minimum volume to classify audio as speech (0–1)
start_duration_ms	int	200	Duration of speech required to trigger start event
stop_duration_ms	int	500	Duration of silence required to trigger stop event
backbuffer_duration_ms	int	1000	Audio buffer captured before speech detection triggers

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Documentation

• Deepslate Documentation
• API Reference

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License

Apache License 2.0 — see LICENSE for details.