End-of-Turn Detection Parameters

Flux provides three configurable parameters that control end-of-turn detection behavior, allowing you to optimize your voice agent’s conversational flow for your specific use case.

Overview

Flux’s end-of-turn detection is powered by three key parameters:

Parameter Details

eot_threshold

Confidence threshold required to trigger an EndOfTurn event, signaling that the user has finished speaking.

Valid Values: 0.5 to 0.9 Default: 0.7 Type: Float (passed as string in URL or SDK)

Behavior:

• Higher values (e.g., 0.8 - 0.9) = Higher certainty required before ending a turn, fewer false positives, slightly increased latency
• Lower values (e.g., 0.5 - 0.7) = Lower certainty required before ending a turn, faster responses, more false positives

Example:

$
wss://api.deepgram.com/v2/listen?model=flux-general-en&eot_threshold=0.8

eager_eot_threshold

Confidence threshold for triggering EagerEndOfTurn events, enabling early LLM response generation.

Valid Values: 0.3 to 0.9 Default: Not set (eager mode disabled) Type: Float (passed as string in URL or SDK)

Behavior:

• When set: Enables EagerEndOfTurn and TurnResumed events
• Lower values (e.g., 0.3 - 0.5) = Earlier triggers, lower latency, more false starts
• Higher values (e.g., 0.6 - 0.8) = More conservative, fewer cancellations, less latency benefit

Trade-offs:

• ✅ Reduces E2E agent latency
• ❌ Increases LLM calls
• ❌ Requires handling EagerEndOfTurn speculative generation and TurnResumed cancellations

Example:

$
wss://api.deepgram.com/v2/listen?model=flux-general-en&eager_eot_threshold=0.6&eot_threshold=0.8

eot_timeout_ms

Maximum silence duration before forcing an EndOfTurn, regardless of confidence.

Valid Values: 500 to 10000 (milliseconds) Default: 5000 (5 seconds) Type: Integer (passed as string in URL or SDK)

Behavior:

• Forces EndOfTurn after specified silence duration, even if confidence is below eot_threshold
• Timer resets when new speech is detected
• Increase (e.g., 7000 - 10000) for users with frequent pauses
• Decrease (e.g., 3000 - 4000) for rapid-response environments

Example:

$
wss://api.deepgram.com/v2/listen?model=flux-general-en&encoding=linear16&sample_rate=16000&eot_timeout_ms=7000

Parameter Interactions

Validation Rules

• eager_eot_threshold must be less than or equal to eot_threshold (if both are set)
• Setting eager_eot_threshold > eot_threshold will result in an error
• All parameters are optional, but their values must be within valid ranges if specified

Common Configurations

Simple Mode (Default)

1
async with client.listen.v2.connect(
2
    model="flux-general-en",
3
    eot_threshold="0.7"  # Default value
4
) as connection:
5
    pass

Best for: Basic conversational agents, demos, getting started

Low-Latency Mode

1
async with client.listen.v2.connect(
2
    model="flux-general-en",
3
    eager_eot_threshold="0.4",
4
    eot_threshold="0.7",
5
    eot_timeout_ms="6000"
6
) as connection:
7
    pass

Best for: High-volume customer service, fast-paced Q&A, responsiveness over accuracy

High-Reliability Mode

1
async with client.listen.v2.connect(
2
    model="flux-general-en",
3
    eot_threshold="0.85",
4
    eot_timeout_ms="8000"
5
) as connection:
6
    pass

Best for: Medical/legal transcription, critical documentation, formal settings

Complex Pipeline Mode

1
async with client.listen.v2.connect(
2
    model="flux-general-en",
3
    eager_eot_threshold="0.4",
4
    eot_threshold="0.85",
5
    eot_timeout_ms="7000"
6
) as connection:
7
    pass

Best for: RAG systems, tool-calling agents, multi-step reasoning workflows

Related Resources

• Getting Started with Flux - Quickstart guide with basic configuration
• Flux State Machine - Understanding turn events and state transitions
• Eager End-of-Turn Optimization - Deep dive on eager mode implementation
• Build a Voice Agent - Complete voice agent implementation guide
• Migrating from Nova-3 - Migration guide with configuration examples