Enum LiveEvent 

#[non_exhaustive]
pub enum LiveEvent {
    Audio(Bytes),
    TextDelta(String),
    TextComplete(String),
    InputTranscript {
        text: String,
        is_final: bool,
    },
    OutputTranscript {
        text: String,
        is_final: bool,
    },
    Thought(String),
    VadStart,
    VadEnd,
    Extraction {
        name: String,
        value: Value,
    },
    ExtractionError {
        name: String,
        error: String,
    },
    StatePromotion {
        extractor: String,
        field: String,
        state_key: String,
        accepted: bool,
        reason: String,
        value: Value,
    },
    PhaseTransition {
        from: String,
        to: String,
        reason: String,
    },
    ToolExecution {
        name: String,
        args: Value,
        result: Value,
    },
    ToolCancelled {
        ids: Vec<String>,
    },
    TurnComplete,
    Interrupted,
    Connected,
    Disconnected {
        reason: Option<String>,
    },
    Error(String),
    GoAway {
        time_left: Duration,
    },
    Telemetry(Value),
    TurnMetrics {
        turn: u32,
        latency_ms: u32,
        prompt_tokens: u32,
        response_tokens: u32,
    },
}

Semantic events emitted by the Live session processor.

The L1 equivalent of L0’s SessionEvent. L0 events are wire-level; LiveEvents are semantic (extractions completed, phases transitioned, tools executed).

Subscribe via LiveHandle::events(). Multiple independent subscribers supported. Zero-cost when no subscribers exist (broadcast::send with 0 receivers is a no-op).

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Audio(Bytes)

Raw PCM audio from model. Uses Bytes (refcounted) — clone is a pointer increment (~2ns), not a deep copy.

TextDelta(String)

Incremental text token from model.

TextComplete(String)

Complete text response (all deltas concatenated).

InputTranscript

User speech transcription.

Fields

text: String

The transcribed text content.

is_final: bool

Whether this is the final transcription for the utterance.

OutputTranscript

Model speech transcription.

Fields

text: String

The transcribed text content.

is_final: bool

Whether this is the final transcription for the utterance.

Thought(String)

Model reasoning/thinking content.

VadStart

Voice activity detected — user started speaking.

VadEnd

Voice activity ended — user stopped speaking.

Extraction

Extraction completed. Emitted for both the top-level result AND each flattened key (e.g., “order.items”, “order.phase”).

Fields

name: String

Extractor name, or "extractor.field" for flattened keys.

value: Value

The extracted JSON value.

ExtractionError

Extraction failed.

Fields

name: String

Name of the extractor that failed.

error: String

Human-readable error description.

StatePromotion

A raw extraction field was considered for promotion into authoritative state.

Fields

extractor: String

Extractor name that produced the field.

field: String

Field name inside the extractor result.

state_key: String

State key targeted by the promotion rule.

accepted: bool

Whether the promotion was accepted and written.

reason: String

Human-readable reason for the decision.

value: Value

Extracted value that was considered.

PhaseTransition

Phase machine transitioned.

Fields

from: String

Phase the machine transitioned from.

to: String

Phase the machine transitioned to.

reason: String

Human-readable reason for the transition.

ToolExecution

Tool dispatched and result obtained.

Fields

name: String

Name of the tool that was called.

args: Value

Arguments passed to the tool.

result: Value

Result returned by the tool.

ToolCancelled

Tool calls cancelled — either by the server (a ToolCallCancelled wire event) or locally when a user barge-in interrupted an in-flight inline tool. No response is sent for a cancelled call, and a cancelled call never advances the governed flow.

Fields

ids: Vec<String>

IDs of the cancelled tool calls.

TurnComplete

Model completed a conversational turn.

Interrupted

Model output interrupted by user speech.

Connected

Session connected to Gemini.

Disconnected

Session disconnected.

Fields

reason: Option<String>

Optional reason for disconnection (server-provided or error message).

Error(String)

Unrecoverable error.

GoAway

Server requesting session wind-down.

Fields

time_left: Duration

Time remaining before the server closes the connection.

Telemetry(Value)

Aggregated session telemetry snapshot.

TurnMetrics

Per-turn latency and token metrics.

Fields

turn: u32

Turn number (1-indexed).

latency_ms: u32

End-to-end latency for this turn in milliseconds.

prompt_tokens: u32

Number of prompt tokens consumed.

response_tokens: u32

Number of response tokens generated.

Trait Implementations

impl Clone for LiveEvent

fn clone(&self) -> LiveEvent

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LiveEvent

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.