Mastra 发布 MCP Events、可观测性升级与多项破坏性变更
原标题：October 21, 2026
AI 摘要
Mastra 发布更新，引入实验性 MCP Events（SEP-3415 草案），允许 MCP 服务器发布事件流，客户端可通过轮询、长连接或签名 webhook 接收，并在 Studio 中检查事件类型与测试发送。可观测性方面新增 span 聚合存储契约、首块耗时（timeToFirstChunkMs）字段及更丰富的 trace/span 查询能力。此外，Agent Controller 会话改为以 sessionId 寻址以支持单资源多会话，沙箱新增原生文件系统 API，Connect 增加按终端用户隔离的连接作用域与 Microsoft Teams 渠道，并包含多项破坏性变更。
正文节选
## Highlights ### MCP Events (poll/stream/webhooks + Studio inspection) Experimental MCP Events (SEP-3415 draft) let MCP servers publish event streams that clients can poll, keep a stream open for, or receive via signed webhooks. Core/server/client add inspection APIs so Studio can list event types, stream occurrences, and test-emit events under `mastra dev`. ### Observability Upgrades: Span Aggregation + “Time to First Chunk” + Richer Trace/Span Querying New `aggregateSpans()` storage c