Java SDK

Parameter

Type

Description

model

String

The Qwen-Omni model to use. See Model list.

url

String

The endpoint URL:

• Singapore region: wss://{WorkspaceId}.ap-southeast-1.maas.aliyuncs.com/api-ws/v1/realtime

• Beijing region: wss://{WorkspaceId}.cn-beijing.maas.aliyuncs.com/api-ws/v1/realtime

Replace {WorkspaceId} with your actual workspace ID.

Parameter

Type

Description

modalities

List<OmniRealtimeModality>

The model output modality. Set to [OmniRealtimeModality.TEXT] for text only, or [OmniRealtimeModality.TEXT, OmniRealtimeModality.AUDIO] for both audio and text.

voice

String

The voice for audio output. For supported voices, see Voice list.

Default voice:

• Qwen3.5-Omni series model: "Tina"

• Qwen3-Omni-Flash-Realtime series model: "Cherry"

• Qwen-Omni-Turbo-Realtime series model: "Chelsie"

inputAudioFormat

OmniRealtimeAudioFormat

The format of the user's input audio. Currently only supports PCM_16000HZ_MONO_16BIT, which represents a PCM audio stream at a 16 kHz sample rate.

outputAudioFormat

OmniRealtimeAudioFormat

The format of the model's output audio. Currently only supports PCM_24000HZ_MONO_16BIT, which represents a PCM audio stream at a 24 kHz sample rate.

instructions

String

A system message that sets the goal or role for the model.

Example: "You are an AI customer service agent for a five-star hotel. Answer customer questions about room types, facilities, prices, and booking policies accurately and in a friendly manner. Always respond professionally and helpfully. Do not provide unverified information or information outside the scope of the hotel's services."

conversation.updateSession(OmniRealtimeConfig.builder()
        .modalities(Arrays.asList(OmniRealtimeModality.AUDIO, OmniRealtimeModality.TEXT))
        .voice("Tina")
        .enableTurnDetection(true)
        .enableInputAudioTranscription(true)
        .parameters(Map.of(
                "instructions", "You are a personal assistant named Xiaoyun"
        ))
        .build()
);

smooth_output

Boolean

This parameter is supported only by the Qwen3-Omni-Flash-Realtime series.

• true: The model provides conversational responses.

• false: The model provides more formal, written-style responses.

  However, performance may be suboptimal if the content is difficult to read aloud.

• null: The default value. The model automatically chooses between conversational and formal response styles.

Set smooth_output using the OmniRealtimeConfig instance's parameters method. The usage is the same as instructions.

enableInputAudioTranscription

Boolean

Enables speech recognition for input audio.

InputAudioTranscription

String

Speech recognition model for input audio transcription. The value is always qwen3-asr-flash-realtime. This parameter is not configurable.

enableTurnDetection

Boolean

Enables VAD. If disabled, you must manually submit audio to create a response.

turnDetectionType

String

The VAD type. Valid values:

• server_vad (default): Detects the end of user speech based on acoustic features.

• semantic_vad: Detects the end of user speech based on semantic validity. This mode can filter out meaningless speech, such as backchannels and background noise. This option is supported only by the Qwen3.5-Omni-Realtime series model.

turnDetectionThreshold

Float

VAD detection threshold. Increase in noisy environments and decrease in quiet environments.

• The closer the value is to -1, the more likely noise is to be detected as speech.

• The closer the value is to 1, the less likely noise is to be detected as speech.

Default: 0.5. Valid values: [-1.0, 1.0].

turnDetectionSilenceDurationMs

Integer

Silence duration that indicates end of speech. If exceeded, the model triggers a response. Default: 800. Valid values: [200, 6000].

turnDetectionParam

Map

Additional turn_detection configuration parameters. Currently supports idle_timeout_ms (Integer): the idle timeout in milliseconds. Applies only to qwen3.5-omni-plus-realtime and qwen3.5-omni-flash-realtime models in server_vad mode. After the server finishes audio playback and the user remains silent beyond this duration (no speech.started triggered), the model proactively generates a response to prompt the user to continue the conversation. Valid range: [5000, 30000].

Example: turnDetectionParam(Map.of("idle_timeout_ms", 5000))

enable_search

Boolean

This parameter takes effect only when you use the Qwen3.5-Omni-Realtime series model.

Enables web search. Default: false. When enabled, the model can search the web to answer real-time questions.

enable_search and search_options parameters must be set using the parameters method of the OmniRealtimeConfig instance. The process is the same for instructions.

Tool calling (tools) and web search (enable_search) are incompatible and cannot be enabled at the same time.

search_options

Object

Web search option settings. This parameter takes effect only after enable_search is enabled. You can set enable_source (Boolean) to true to return a list of search result sources.

search_options using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

tools

List<Map<String, Object>>

This parameter takes effect only when you use the Qwen3.5-Omni-Realtime series model.

Tool definitions. When provided, the model can call external tools to respond to user questions. If a tool is called, the model does not generate audio and only returns the tool calling parameters.

Each tool is a Map that contains the following fields:

• type (String, required): The value is fixed to "function".

• function (Map, required): The definition of the tool function. This field contains the following subfields:

  • name (String, required): A custom name for the tool function. We recommend that you use the same name as the function, such as get_current_weather or get_current_time.

  • description (String, optional): A description of the tool function. The model uses this description to decide whether to call the function.

  • parameters (Map, optional): Input parameter descriptions. The model uses them to extract parameters. If the tool function does not require input parameters, you do not need to specify this field. This field contains the following subfields:

    • type (String, required): The value is fixed to "object".

    • properties (Map, optional): Describes the name, data type, and description of each input parameter. The Key is the parameter name, and the Value is a Map that contains the data type (type) and description (description).

    • required (List, optional): Specifies which input parameters are required.

search_options using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

temperature

Float

Sampling temperature that controls content diversity.

Higher values produce more diverse content; lower values produce more deterministic content.

Valid values: [0, 2).

Because both temperature and top_p control content diversity, we recommend that you set only one of them.

Default values of temperature:

• Qwen3.5-Omni-Realtime series model: 0.7

• qwen3-omni-flash-realtime series model: 0.9

• qwen-omni-turbo-realtime series model: 1.0

qwen-omni-turbo models do not support modification.

temperature parameter using the parameters method of the OmniRealtimeConfig instance, in the same way you set the instructions parameter.

top_p

Float

Probability threshold for nucleus sampling that controls content diversity.

Higher values produce more diverse content; lower values produce more deterministic content.

Valid values: (0, 1.0].

Because both temperature and top_p control content diversity, we recommend that you set only one of them.

Default values of top_p:

• Qwen3.5-Omni-Realtime series model: 0.8

• qwen3-omni-flash-realtime series model: 1.0

• qwen-omni-turbo-realtime series model: 0.01

qwen-omni-turbo models do not support modification.

top_p using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

top_k

Integer

Candidate set size for sampling. For example, 50 means only the 50 highest-scoring tokens form the candidate set. Larger values increase randomness; smaller values increase determinism. Set to None or a value greater than 100 to disable top_k and use only top_p.

The value must be greater than or equal to 0.

Default values of top_k:

• Qwen3.5-Omni-Realtime series model: 20

• qwen3-omni-flash-realtime series model: 50

• qwen-omni-turbo-realtime series model: 20

qwen-omni-turbo models do not support modification.

top_k using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

max_tokens

Integer

Maximum number of tokens to return.

max_tokens setting does not affect the generation process of the model. If the number of tokens generated by the model exceeds max_tokens, the returned content is truncated.

Default and maximum values equal the model's maximum output length. See Model list for details.

Use max_tokens to limit output length for generating summaries, keywords, controlling costs, or reducing response time.

qwen-omni-turbo models do not support modification.

max_tokens using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

repetition_penalty

Float

Controls repetition in generated sequences. Higher values reduce repetition. 1.0 means no penalty. Must be greater than 0.

Default values of repetition_penalty:

• Qwen3.5-Omni-Realtime series model: 1.0

• Other models: 1.05

qwen-omni-turbo models do not support modification.

repetition_penalty using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

presence_penalty

Float

Controls content repetition in model output.

Valid values: [-2.0, 2.0]. Positive values reduce repetition; negative values increase it.

Default values of presence_penalty:

• Qwen3.5-Omni-Realtime series model: 1.5

• Other models: 0.0

Scenarios:

Higher values suit scenarios requiring diversity or creativity, such as creative writing or brainstorming.

Lower values suit scenarios requiring consistency or technical precision, such as technical documents.

qwen-omni-turbo models do not support modification.

presence_penalty using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.

seed

Integer

Makes generation more deterministic, ensuring consistent results across runs.

Passing the same seed with identical parameters produces the same result as much as possible.

Valid values: 0 to 2³¹−1. Default value: -1.

qwen-omni-turbo models do not support modification.

seed using the OmniRealtimeConfig instance's parameters method. The usage is the same as for instructions.