Mastra `@mastra/core@1.45.0` speeds up long-thread resume and fixes agent signal handling
`@mastra/core@1.45.0` ships faster long-thread resumption by avoiding full message scans, fixes agent signal drain bugs, clarifies system guidance on automatic state signals, redesigns Studio UI panels, and patches a WorkOS OAuth PKCE login failure.
Score breakdown
The long-thread resume optimization and signal-drain correctness fixes directly address reliability and cost bottlenecks in stateful, multi-turn agent workflows built on Mastra.
- 01@mastra/core bumped to v1.45.0 with no breaking changes
- 02State signal restoration no longer scans every message, speeding up long-thread resume
- 03Agent signal drain fix prevents follow-up signal turns from attaching to the wrong assistant response and ensures response message IDs rotate consistently
`@mastra/core@1.45.0` addresses a performance bottleneck in long-thread workflows: state signal restoration previously required scanning every message in a thread, and the new approach eliminates that scan, making resumption of very long threads significantly cheaper and faster.
On the correctness side, agent signal drain handling received two related fixes.
On the correctness side, agent signal drain handling received two related fixes. Pending signals are now recorded through the canonical signal transcript path, and response message IDs rotate consistently across turns. Together these changes prevent follow-up signal turns from being attached to the previous assistant response, ensuring the agent sees the latest completed step before continuing. Complementing this, new system guidance clarifies that browser and task-list state signals are automatic context updates rather than user instructions, reducing prompt confusion and accidental instruction-following.
`@mastra/playground-ui` gains a redesigned Studio panel and code-surface UI with true resizable panels featuring smooth open/close animation, mobile drawer behavior via `PanelDrawer`, a new `useIsMobile` hook, `CodeBlock.actions` for header controls, and new popover collision-avoidance alignment controls. Separately, `@mastra/auth-workos` fixes an OAuth/SSO login failure caused by a missing PKCE verifier cookie, restoring reliable WorkOS sign-in for both single-auth and dual-auth setups. The changelog notes no breaking changes in this release.
Key facts
- 01@mastra/core bumped to v1.45.0 with no breaking changes
- 02State signal restoration no longer scans every message, speeding up long-thread resume
- 03Agent signal drain fix prevents follow-up signal turns from attaching to the wrong assistant response and ensures response message IDs rotate consistently
- 04New system guidance clarifies browser and task-list state signals are automatic context updates, not user instructions
- 05@mastra/playground-ui adds resizable Studio panels, PanelDrawer mobile drawer, useIsMobile hook, and CodeBlock.actions
- 06@mastra/auth-workos fixes a missing PKCE verifier cookie that broke WorkOS OAuth/SSO login for single-auth and dual-auth setups
Topics
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