November 2, 2026
Mastra's November 2026 release adds restart-safe MCP tasks backed by storage, background tasks for non-agent owners, observability enhancements (TTFT, outcomes, stop reasons), authenticated channel attachment handling, and browser cookie injection, alongside breaking changes in playground-ui and core imports.
Why this signal matters
Mastra has announced its November 2, 2026 release with several major ecosystem and core updates: - MCP Tasks : Added experimental storage-backed MCP tasks in @mastra/mcp that allow long-running tools, agents, and workflows to return task handles, persist state across restarts, and support cross-instance polling, answering, and cancellation. - Background Tasks : Added support for non-agent owners (such as MCP servers) with configurable retention ( expiresAt /metadata), per-owner concurrency overrides, and queued resumes ( { onNoSlot: 'queue' } ). - Observability : Added execution outcomes, typed stopReason , model/provider metadata, and time-to-first-token ( timeToFirstTokenMs ) reporting across ClickHouse, DuckDB, and Postgres storage. Core also adds schemas for custom dashboard definitions and saved list views, paired with UI rendering components in @mastra/playground-ui . - Agents & Workspaces : Workspace agents can now fetch authenticated binary attachments (e.g., Slack ZIP/DOCX) into channel-attachments/ with configurable storage limits (defaulting to 100 MiB), while text attachments are inlined. Workspace write protection is now opt-in via requireReadBeforeWrite . - Browser & Sandbox Tooling : MastraBrowser gains setCookies() to set session cookies for browser threads without leaking tokens to the LLM. Sandbox environments support factory-scoped credential provisioning via factoryId . - Breaking Changes : Removed subpaths @mastra/core/network/vNext and @mastra/core/telemetry/otel-vendor . @mastra/playground-ui removed ChartCard description/summary fields, specific…
Actionable summary
Mastra release introduces experimental @mastra/mcp storage-backed tasks, non-agent background task retention/concurrency controls, and observability metrics (TTFT, provider/model tracking, stopReason). Channel agents gain authenticated binary file attachment downloads to workspaces, and MastraBrowser adds setCookies() . Breaking changes include removed subpaths in @mastra/core and chart/hover API cleanups in…
- Agent usefulness
- 77/100
- Confidence
- 96%
- Canonical data
- JSON + Markdown
What builders should check
- Remove runtime imports targeting @mastra/core/network/vNext and @mastra/core/telemetry/otel-vendor .
- Update @mastra/playground-ui metrics and card components to align with the revised chart API and remove deprecated fluid-hover utilities.
- Migrate deprecated board definitions ( defineBoard() , title , role , next ) to stored boards APIs ( name , runner.context , nextPhases ).
- Set requireReadBeforeWrite explicitly if opt-in workspace write protection against StaleFileError is required.