Enum AgentEvent 

pub enum AgentEvent {
    Provider(ProviderEvent),
    ToolStart {
        tool_call_id: String,
        name: String,
    },
    ToolEnd {
        tool_call_id: String,
        result: ToolCallResult,
    },
    Retry {
        tool_call_id: String,
        attempt: usize,
        max_attempts: usize,
        reason: String,
    },
    LoopEnd {
        result: ToolUseResult,
    },
    LoopError {
        error: LlmError,
        iterations: usize,
        messages: Vec<Message>,
    },
}

Agent 层流式事件 — 封闭、强类型、exhaustive match

终态契约：

• 正常结束：LoopEnd 恰好一次，然后 channel 关闭
• 异常结束：LoopError 恰好一次，然后 channel 关闭
• 终态事件后不再发送任何事件

Variants

Provider(ProviderEvent)

Provider 层事件

ToolStart

工具开始执行

Fields

tool_call_id: String

name: String

ToolEnd

工具执行完成

Fields

tool_call_id: String

result: ToolCallResult

Retry

工具重试

Fields

tool_call_id: String

attempt: usize

max_attempts: usize

reason: String

LoopEnd

Agent loop 正常结束（恰好一次，后不再发送）

Fields

result: ToolUseResult

LoopError

Agent loop 异常结束（恰好一次，后不再发送）

Fields

error: LlmError

iterations: usize

messages: Vec<Message>

Trait Implementations

impl Debug for AgentEvent

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

Formats the value using the given formatter.