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Experimental config

The experimental config file is an optional JSON file used to enable experimental features and advanced runtime settings for an agent.

Use it for:

  • feature flags
  • ASR tuning
  • conversation control
  • debug-oriented options

Location

The file lives at:

agent_settings/experimental_config.json

What it contains

The file is a JSON object.

It may be:

  • flat
  • nested
  • grouped by feature category

Top-level keys represent feature areas, and values contain the settings for those features.

Example

{
  "asr": {
    "disable_itn": true,
    "eager_final": true
  },
  "conversation_control": {
    "enhanced_tts_preprocessing_enabled": false,
    "max_silence_count": 1000,
    "min_chunk_size": 1
  }
}

Schema and validation

Available features and their types are defined in:

src/poly/resources/experimental_config_schema.yaml

The ADK validates experimental_config.json against this schema when you run:

poly validate

Invalid configuration fails poly validate locally. Experimental config that fails validation is not read by the runtime in deployed agents.

Validate before pushing

Experimental config can affect runtime behavior in subtle ways. Always run poly validate locally before pushing changes.

When to use it

Use experimental config when you need behavior that goes beyond the standard Agent Studio settings.

Common use cases include:

  • ASR and TTS tuning

    Adjust speech recognition or speech output behavior beyond the standard channel settings.

  • Experimental platform features

    Enable features before they are generally available.

  • Conversation control

    Tune parameters such as silence handling or chunk size behavior.

Feature reference

The following sections describe notable feature areas available in the schema.

Audio enhancement

Configure audio enhancement processing applied to the incoming audio stream before speech recognition. Three providers are available: ai-coustics, dolby, and krisp.

krisp

Krisp provides noise cancellation and voice isolation. Settings include:

Field Type Description Default
model string Krisp model variant: "noise-cancellation", "voice-isolation", "telephony", "telephony-lite", "transcription" "telephony-lite"
noise_suppression_level integer Noise suppression intensity. 0 = off, 100 = max. 100
frame_duration_ms integer Audio frame duration in milliseconds. Allowed values: 10, 15, 20, 30, 32. 20
timeout_ms integer Max milliseconds to wait for enhancement per chunk before falling back to original audio. 0 = no timeout. 100

Example:

{
  "audio_enhancement": {
    "krisp": {
      "model": "telephony-lite",
      "noise_suppression_level": 100,
      "frame_duration_ms": 20,
      "timeout_ms": 100
    }
  }
}

DTMF

Configure DTMF behavior, including disabling speech recognition for DTMF-only steps.

The dtmf object supports a flow_overrides map where each key is a flow name. Per-flow settings include:

Field Type Description
disable_speech boolean Whether to disable speech recognition when DTMF is enabled for this flow.
steps object Step-specific overrides. Each key is a step name.

Per-step settings (nested under steps) include:

Field Type Description
disable_speech boolean Whether to disable speech recognition for this step. Takes precedence over the flow-level setting.
first_digit_timeout integer Timeout in seconds for the first DTMF digit input for this step. Minimum: 1.

Example:

{
  "dtmf": {
    "flow_overrides": {
      "Payment Flow": {
        "disable_speech": true,
        "steps": {
          "Enter Card Number": {
            "disable_speech": true,
            "first_digit_timeout": 5
          }
        }
      }
    }
  }
}

Memory

Configure agent memory features, including repeat-caller identification.

identifier_source

By default, memory lookups use the caller or callee phone number as the identifier. The identifier_source field lets you supply a custom source instead.

Field Type Description
identifier_source string Custom source for the memory lookup identifier. Must match the pattern (sip_headers\|integration_attributes\|state):.+.

Example:

{
  "memory": {
    "identifier_source": "sip_headers:X-Customer-Id"
  }
}

OpenAI Realtime

Configure behavior for the OpenAI Realtime integration, including transcription settings.

set_transcriber_language

Field Type Description Default
set_transcriber_language boolean When true, the conversation language code is passed to the transcriber in the session configuration, making the model adhere more strictly to the specified language. Do not use this in multilingual projects with a language detection component. false

Example:

{
  "openai_realtime": {
    "transcription": {
      "set_transcriber_language": true
    }
  }
}

include_kb_functions_in_flows

Controls whether knowledge base (KB) functions from retrieved RAG topics are shown to the model inside flows.

Value Behavior
true KB functions from retrieved RAG topics are shown to the model inside flows, even on steps that have their own functions_referenced.
false (default) KB functions are hidden inside flows.

This setting only affects behavior inside flows. Outside flows, KB functions are always shown. It can be overridden per-flow or per-step.

Best practices

  • only set values you actually intend to override
  • omit defaults rather than copying them unnecessarily
  • validate locally with poly validate before pushing
  • remove flags that are no longer needed
  • treat the file as an advanced override layer, not a dumping ground for ordinary config

  • Agent settings

    See where experimental config sits within the broader agent settings area. Open agent settings

  • Speech recognition

    Compare experimental ASR controls with standard voice speech-recognition settings. Open speech recognition