Enum AgentEvent 

pub enum AgentEvent {
    Token(String),
    ToolCallStart {
        id: String,
        name: String,
    },
    ToolCallArgsDelta {
        id: String,
        delta: String,
    },
    ToolCall(ToolCallInfo),
    ToolResult(ToolCallResult),
}

Events emitted by AgentStream.

Each variant represents a distinct, self-contained event in the agent lifecycle:

• Token(String) — a text fragment from the assistant. In streaming mode each Token is a single SSE delta; in non-streaming mode the full response text arrives as one Token.
• ToolCallStart { id, name } — emitted the moment a tool call’s name is known during streaming, before any arguments have arrived. Allows UIs to show the tool name immediately. Only emitted in streaming mode.
• ToolCallArgsDelta { id, delta } — an incremental fragment of the tool call’s JSON arguments, emitted once per SSE chunk during streaming. Accumulate these to reconstruct the full arguments string. Only emitted in streaming mode.
• ToolCall(ToolCallInfo) — the model has requested a tool invocation, emitted once the full arguments are assembled (end of stream). In non-streaming mode this is the only tool-call event. Execution begins after this event.
• ToolResult(ToolCallResult) — a tool has finished executing. One event is emitted per call, in the same order as the corresponding ToolCall events.

Variants

Token(String)

ToolCallStart

Emitted in streaming mode the instant a tool call’s id+name are known.

Fields

id: String

name: String

ToolCallArgsDelta

Emitted in streaming mode for each incremental fragment of the arguments JSON.

Fields

id: String

delta: String

ToolCall(ToolCallInfo)

ToolResult(ToolCallResult)

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.