Struct AgentContext 

pub struct AgentContext<B: ContextBackend> { /* private fields */ }

LLM 对话上下文管理器，kameo Actor。

管理三区 + Scratch 消息模型（immutable → compressed → incremental → scratch），提供：

• 消息增删改查（AppendMsg、UpdateMsg、RemoveMsg 等）
• 对话发送（SendMsg、SendStreamMsg），支持通过 ScratchOpts 追加临时元数据
• 上下文压缩（CompressMsg）
• Token 估算和溢出检测（EstimateTokensMsg、IsFullMsg）
• 变更回调（ChangeEvent）

构造

let ctx = AgentContext::new(backend, vec![])
    .with_on_change(|event| { /* 处理变更 */ });
let actor = AgentContext::spawn(ctx);

Implementations

impl<B: ContextBackend> AgentContext<B>

pub fn new(backend: B, immutable: Vec<B::Message>) -> Self

创建新的上下文管理器。

• backend: 实现了 ContextBackend 的 LLM 后端实例
• immutable: 初始不可变消息（系统提示词等），放入 immutable 区

pub fn with_on_change( self, f: impl Fn(ChangeEvent<B::Message>) + Send + Sync + 'static, ) -> Self

注册增量区变更回调。

每次对 incremental 区的写操作（追加/更新/插入/移除/清空等）都会触发此回调。 用于 CLI 实时展示、日志记录等场景。

pub fn with_on_compressed( self, f: impl Fn(Vec<B::Message>, Vec<B::Message>) -> (Vec<B::Message>, Vec<B::Message>) + Send + Sync + 'static, ) -> Self

注册压缩后处理回调。

在 CompressMsg 生成摘要后、写入 compressed 区之前调用。 回调接收 (摘要消息列表, 保留消息列表)，返回 (最终摘要, 最终保留)。 用于自定义后处理（如过滤、重新排序摘要内容）。

Trait Implementations

impl<B: ContextBackend> Actor for AgentContext<B>

type Args = AgentContext<B>

Arguments to initialize the actor.

type Error = Infallible

Actor error type.

fn name() -> &'static str

The name of the actor, which can be useful for logging or debugging.

async fn on_start( state: Self::Args, _actor_ref: ActorRef<Self>, ) -> Result<Self, Self::Error>

Called when the actor starts, before it processes any messages.

fn supervision_strategy() -> SupervisionStrategy

Defines the supervision strategy for this actor when acting as a supervisor.

fn on_message( &mut self, msg: Box<dyn DynMessage<Self>>, actor_ref: ActorRef<Self>, tx: Option<Sender<Result<Box<dyn Any + Send>, SendError<Box<dyn Any + Send>, Box<dyn Any + Send>>>>>, stop: &mut bool, ) -> impl Future<Output = Result<(), Box<dyn ReplyError>>> + Send

Called when the actor receives a message to be processed.

fn on_panic( &mut self, actor_ref: WeakActorRef<Self>, err: PanicError, ) -> impl Future<Output = Result<ControlFlow<ActorStopReason>, Self::Error>> + Send

Called when the actor encounters a panic or an error during “tell” message handling.

fn on_link_died( &mut self, actor_ref: WeakActorRef<Self>, id: ActorId, reason: ActorStopReason, ) -> impl Future<Output = Result<ControlFlow<ActorStopReason>, Self::Error>> + Send

Called when a linked actor dies.

fn on_stop( &mut self, actor_ref: WeakActorRef<Self>, reason: ActorStopReason, ) -> impl Future<Output = Result<(), Self::Error>> + Send

Called before the actor stops.

fn next( &mut self, actor_ref: WeakActorRef<Self>, mailbox_rx: &mut MailboxReceiver<Self>, ) -> impl Future<Output = Result<Option<Signal<Self>>, Self::Error>> + Send

Awaits the next signal typically from the mailbox.

impl<B: ContextBackend> Message<AppendMsg<<B as ContextBackend>::Message>> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, msg: AppendMsg<B::Message>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<ClearMsg> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, _msg: ClearMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<CompressMsg<<B as ContextBackend>::Opts>> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, msg: CompressMsg<B::Opts>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<CompressedMsg> for AgentContext<B>

type Reply = Vec<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: CompressedMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<EstimateTokensMsg> for AgentContext<B>

type Reply = usize

The reply sent back to the message caller.

async fn handle( &mut self, _msg: EstimateTokensMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<ExtendMsg<<B as ContextBackend>::Message>> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, msg: ExtendMsg<B::Message>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<FindByRoleMsg> for AgentContext<B>

type Reply = Vec<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, msg: FindByRoleMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<FromJsonlMsg> for AgentContext<B>

type Reply = Result<(), AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, msg: FromJsonlMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<Get> for AgentContext<B>

type Reply = Option<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, msg: Get, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<ImmutableMsg> for AgentContext<B>

type Reply = Vec<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: ImmutableMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<IncrementalMsg> for AgentContext<B>

type Reply = Vec<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: IncrementalMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<InsertMsg<<B as ContextBackend>::Message>> for AgentContext<B>

type Reply = Result<(), AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, msg: InsertMsg<B::Message>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<IsEmpty> for AgentContext<B>

type Reply = bool

The reply sent back to the message caller.

async fn handle( &mut self, _msg: IsEmpty, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<IsFullMsg> for AgentContext<B>

type Reply = bool

The reply sent back to the message caller.

async fn handle( &mut self, _msg: IsFullMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<Len> for AgentContext<B>

type Reply = usize

The reply sent back to the message caller.

async fn handle( &mut self, _msg: Len, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<MessagesMsg> for AgentContext<B>

type Reply = Vec<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: MessagesMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<PopMsg> for AgentContext<B>

type Reply = Option<<B as ContextBackend>::Message>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: PopMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<RemoveMsg> for AgentContext<B>

type Reply = Result<(), AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, msg: RemoveMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<RetainMsg> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, msg: RetainMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<SendMsg<<B as ContextBackend>::Opts>> for AgentContext<B>

type Reply = Result<<B as ContextBackend>::Response, AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, msg: SendMsg<B::Opts>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend + Clone> Message<SendStreamMsg<<B as ContextBackend>::Opts>> for AgentContext<B>

type Reply = AgentSendStream<B>

The reply sent back to the message caller.

async fn handle( &mut self, msg: SendStreamMsg<B::Opts>, ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<SilentAppendMsg<<B as ContextBackend>::Message>> for AgentContext<B>

type Reply = ()

The reply sent back to the message caller.

async fn handle( &mut self, msg: SilentAppendMsg<B::Message>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<ToJsonlMsg> for AgentContext<B>

type Reply = Result<String, AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, _msg: ToJsonlMsg, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.

impl<B: ContextBackend> Message<UpdateMsg<<B as ContextBackend>::Message>> for AgentContext<B>

type Reply = Result<(), AgentError>

The reply sent back to the message caller.

async fn handle( &mut self, msg: UpdateMsg<B::Message>, _ctx: &mut Context<Self, Self::Reply>, ) -> Self::Reply

Handler for this message.

fn name() -> &'static str

The name of the message, which can be useful for logging or debugging.