Enum AgentEvent 

pub enum AgentEvent {
    RunStarted {
        session_id: SessionId,
    },
    TurnStarted {
        session_id: SessionId,
        turn_id: TurnId,
    },
    InputAccepted {
        session_id: SessionId,
        items: Vec<Item>,
    },
    ContentDelta(Delta),
    ToolCallRequested(ToolCallPart),
    ToolResultReceived(ToolResultPart),
    ApprovalRequired(ApprovalRequest),
    ApprovalResolved {
        approved: bool,
    },
    ToolCatalogChanged(ToolCatalogEvent),
    MutationStarted {
        session_id: SessionId,
        turn_id: Option<TurnId>,
        mutator: String,
        point: MutationPoint,
    },
    MutationFinished {
        session_id: SessionId,
        turn_id: Option<TurnId>,
        mutator: String,
        dirty: bool,
        metadata: MetadataMap,
    },
    UsageUpdated(Usage),
    Warning {
        message: String,
    },
    RunFailed {
        message: String,
    },
    TurnFinished(TurnResult),
}

Lifecycle and streaming events emitted by the LoopDriver.

Observers (see LoopObserver) receive these events in the order they occur. They are useful for building UIs, logging, or telemetry.

Variants

RunStarted

The agent run has been initialised.

Fields

session_id: SessionId

TurnStarted

A new model turn is starting.

Fields

session_id: SessionId

turn_id: TurnId

InputAccepted

User input has been accepted into the pending queue.

Fields

session_id: SessionId

items: Vec<Item>

ContentDelta(Delta)

Incremental content delta from the model.

ToolCallRequested(ToolCallPart)

The model has requested a tool call.

ToolResultReceived(ToolResultPart)

A tool call’s result has landed in the transcript.

Fires once per Part::ToolResult that’s appended, including the synthetic placeholder that’s pushed when a tool is detached to the background — the real result fires a second event with the same ToolResultPart::call_id once the background task completes. Cancellation/denial paths (auth cancelled, approval denied) also emit this with is_error = true.

Correlate with the matching AgentEvent::ToolCallRequested via call_id.

ApprovalRequired(ApprovalRequest)

A tool call requires explicit user approval before execution.

ApprovalResolved

An approval interrupt has been resolved.

Fields

approved: bool

ToolCatalogChanged(ToolCatalogEvent)

The available tool catalog changed and will be reflected on the next model request.

MutationStarted

A LoopMutator is about to run at one of the mutation points. mutator is a stable label the implementation chooses for itself.

Fields

session_id: SessionId

turn_id: Option<TurnId>

mutator: String

point: MutationPoint

MutationFinished

A LoopMutator has finished running. dirty indicates whether the transcript was modified; metadata carries mutator-specific extras (e.g. compaction reason, replaced item count).

Fields

session_id: SessionId

turn_id: Option<TurnId>

mutator: String

dirty: bool

metadata: MetadataMap

UsageUpdated(Usage)

Updated token usage statistics.

Warning

Non-fatal warning (e.g. a tool failure that was recovered from).

Fields

message: String

RunFailed

The agent run has failed with an unrecoverable error.

Fields

message: String

TurnFinished(TurnResult)

A turn has finished (successfully, via cancellation, etc.).

Trait Implementations

impl Clone for AgentEvent

fn clone(&self) -> AgentEvent

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AgentEvent

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AgentEvent

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for AgentEvent

fn eq(&self, other: &AgentEvent) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for AgentEvent

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for AgentEvent