Session Gateway

createAgentRuntimeClientFromSessionGateway 把产品侧已有 session gateway 包装成标准 AgentRuntimeClient。它用于 Lime 前端 App Server client 的闭包适配，避免 SDK adapter 依赖 this 绑定。

实现锚点：packages/agent-runtime-client/src/sessionGateway.ts。

API

export function createAgentRuntimeClientFromSessionGateway(
  gateway: AgentRuntimeSessionGateway
): AgentRuntimeClient;

Gateway Shape

export type AgentRuntimeSessionGateway = {
  startTurn: AgentRuntimeGatewayMethod<AgentSessionTurnStartParams, AgentSessionTurnStartResponse>;
  readSession: AgentRuntimeGatewayMethod<AgentSessionReadParams, AgentSessionReadResponse>;
  cancelTurn: AgentRuntimeGatewayMethod<AgentSessionTurnCancelParams, AgentSessionTurnCancelResponse>;
  respondAction: AgentRuntimeGatewayMethod<AgentSessionActionRespondParams, AgentSessionActionRespondResponse>;
  exportEvidence?: AgentRuntimeGatewayMethod<EvidenceExportParams, EvidenceExportResponse>;
  nextEvent?(timeoutMs?: number): Promise<AgentSessionEventNotification>;
  drainEvents?(limit?: number): Promise<JsonRpcMessage[]>;
};

Gateway method	Client method
startTurn	runtime.startTurn
readSession	runtime.readThread
cancelTurn	runtime.cancelTurn
respondAction	runtime.respondAction
exportEvidence	runtime.exportEvidence
nextEvent / drainEvents	runtime.nextEvent

Event Routing

Adapter 只接受 JSON-RPC notification：

{
  jsonrpc: "2.0",
  method: "agentSession/event",
  params: { event }
}

非 agentSession/event message 会被忽略，不会进入 projection。

Example

const runtime = createAgentRuntimeClientFromSessionGateway({
  startTurn: (params, options) => appServer.agentSession.turnStart(params, options),
  readSession: (params, options) => appServer.agentSession.read(params, options),
  cancelTurn: (params, options) => appServer.agentSession.turnCancel(params, options),
  respondAction: (params, options) => appServer.agentSession.actionRespond(params, options),
  exportEvidence: (params, options) => appServer.evidence.export(params, options),
  drainEvents: (limit) => appServer.drainEvents(limit)
});

Failure Modes

场景	行为
exportEvidence 未提供	调用时抛出明确错误。
nextEvent 和 drainEvents 都未提供	nextEvent 抛出 event subscription unavailable。
drainEvents 没有返回 agentSession/event	抛出 timeout-aware 错误。
gateway method 抛错	原样传播 transport error。

验证

npm --prefix packages/agent-runtime-client run test

测试必须覆盖 lifecycle、event dispatch、nextEvent、drainEvents、optional exportEvidence fail closed 和 browser-safe 子路径。