Peter Wielander

This commit introduces a **new capability** to **automatically re-enqueue active workflow runs** upon a world restart, significantly improving system resilience. It implements a core `reenqueueActiveRuns` utility function within the `packages/world/src/recovery.ts` module, designed to identify and resume all pending or running workflows. This recovery logic is then integrated into the startup processes of both the **`world-local`** and **`world-postgres`** packages, ensuring that in-progress workflows are not lost after unexpected shutdowns. Comprehensive tests have been added for both local and Postgres world implementations to verify the correct functioning of this critical recovery mechanism. This enhancement prevents workflow interruptions and ensures continuity of operations.

This commit **enhances the documentation** for **Vercel World deployments** by integrating direct links to Vercel's official pricing and limits pages. Specifically, the `docs/content/docs/deploying/world/vercel-world.mdx` file has been updated to provide users with immediate access to crucial cost and usage constraint information. This **documentation update** also includes a reorganization of the existing limitations section for improved readability and clarity. The change aims to provide a more comprehensive and user-friendly resource for developers utilizing Vercel World.

This commit delivers a **bug fix** for the **`builders` package**, resolving an issue where `import.meta.url` was missing in CommonJS (CJS) builds, particularly affecting **workflow and webhook bundling processes**. It introduces a **polyfill** for `import.meta.url` and `import.meta.resolve` within `base-builder.ts` to ensure these properties are correctly available in CJS environments. This prevents runtime errors and ensures proper module path resolution for CJS-built components. Furthermore, **new end-to-end tests** have been added to the `core` package to thoroughly validate the presence and accuracy of `import.meta.url` in bundled step functions.

This commit **refactors** the **`world-local` package's `streamer` module** by extracting common logic for listing stream chunk files into a new helper function, `listChunkFilesForStream`. This **improves code organization and maintainability** within the stream processing logic. Accompanying this change, **new test suites** have been added to `streamer.test.ts` to enhance coverage for `getStreamChunks` pagination and `getStreamInfo` functionality. The overall impact is a **cleaner and better-tested codebase** for stream chunk management, ensuring robustness without altering external behavior.

This commit introduces a **new configuration option**, `rewriteTsExtensions`, within the **`@nx/builders`** package, specifically for `createStepsBundle` and `createSwcPlugin`. This option allows for **conditional rewriting of `.ts` file extensions to `.js`** in externalized imports during the build process. The primary goal is to **fix module resolution issues** by **scoping this rewriting behavior exclusively to `@nx/vitest`**, where it is now explicitly enabled. This ensures proper module loading for Vitest tests while preventing unintended extension changes in other build contexts.

This commit introduces a **critical bug fix** within the **`@ai` package** to prevent the `WorkflowChatTransport` from blocking browser paint during stream reconnects. It addresses a performance issue where intensive stream processing could freeze the user interface, particularly in **browser environments**. The solution involves adding a new `yieldToMacrotask` function to `packages/ai/src/stream-iterator.ts`, which ensures the browser can render updates by yielding control between processing chunks. This significantly improves the **responsiveness and user experience** of AI chat features by eliminating UI freezes during data streaming, with new tests validating the macrotask yielding behavior.

This commit **fixes a bug** in the **documentation tarballing process** by adjusting the build script order in `docs/package.json` from `postbuild` to `prebuild`, ensuring correct packing. To **prevent regressions**, it introduces **new smoke tests** in `docs/scripts/check-docs-smoke.mjs` that specifically verify tarball responses for workflow-related files. These **maintenance** additions include a new helper function to assert gzipped content, significantly enhancing the reliability and correctness of the packaged documentation.

This commit introduces **stream pagination and metadata endpoints**, significantly enhancing the management and resilience of streams across the system. It extends the **`Streamer` interface** with `getStreamChunks` and `getStreamInfo` methods, which are implemented across **`world-local`, `world-postgres`, and `world-vercel` packages** to allow retrieval of specific stream chunks and current tail index information. The **`WorkflowChatTransport`** in the `ai` package now leverages this **new capability** by supporting negative `initialStartIndex` for intelligent stream reconnection, resolving absolute positions using the `x-workflow-stream-tail-index` header. This **feature addition** improves the robustness of **resumable streams**, supported by updated **documentation** for `getTailIndex` usage and new **end-to-end tests** to ensure correct behavior.

This commit introduces a **fix** to the **CLI's update check mechanism**, specifically within `packages/cli/src/lib/update-check.ts`. It modifies the logic in functions like `checkForUpdate` and `checkForUpdateCached` to prevent the system from suggesting an upgrade to a pre-release version (e.g., beta, alpha) when the user is currently on a stable release. This **enhancement** to the update recommendation process ensures a more predictable and stable experience for users of the **CLI**, preventing inadvertent transitions to potentially unstable versions. A corresponding changeset entry has also been added to document this important change.

This commit primarily focuses on **documentation updates** for the **NestJS integration**, reflecting its current **experimental phase**. It **removes the Vercel deployment section** from `nestjs.mdx` and adds a prominent **callout warning** about its unstable status. Additionally, the NestJS integration card in `index.mdx` is updated to "Coming soon" with its link disabled, ensuring users are properly informed about the feature's availability. This **maintenance** task prevents users from attempting to use an experimental feature prematurely, clarifying the current state of the **NestJS Vercel integration**.

This commit introduces a **new capability** to gracefully handle and display **expired run data** across the application's interfaces. It establishes core utility functions like `isExpiredObject` and `isExpiredStub` within `packages/core` to identify expired data placeholders during serialization and hydration. Both the **CLI inspection output** and the **Web UI** (specifically attribute panels and event lists) are enhanced to detect and visually represent expired fields, using `ExpiredDataRef` for CLI warnings and `ExpiredFieldBlock` components for web markers. This **improves observability** by ensuring users are clearly informed when viewing run data that is no longer current or complete.

This commit **reverts** the previously introduced capability to call the `start()` function directly from within **workflow functions**, effectively removing a feature that allowed recursive or nested workflow initiation. This change impacts the **core workflow runtime**, the **SWC plugin's step naming conventions**, and **removes UI components** related to `RunRef` objects and `onRunClick` functionality from the web-shared library. Consequently, users must now invoke `start()` via a dedicated step for background execution, simplifying the **workflow execution model** and **API surface**. Extensive **documentation updates** across `api-reference`, `common-patterns`, and `skill` definitions clarify this revised pattern, while related **e2e tests** have also been removed as part of this significant **refactoring**.

This commit introduces **support for negative `startIndex`** within the **streaming API**, enabling users to specify an offset from the end of a stream. This **new capability** is implemented in the **`packages/world-local`** and **`packages/world-postgres`** streamers, where negative `startIndex` values are now resolved and clamped to 0 if they exceed the available chunk count. Comprehensive **documentation updates** across `packages/core` and `packages/world` interfaces, alongside new **end-to-end and unit tests**, validate this behavior. This enhancement provides greater flexibility for reading data streams by allowing backward indexing.

This commit introduces a **critical fix** within the **`packages/core`** module, specifically addressing the **`WorkflowServerWritableStream`** in `serialization.ts`. It ensures that write operations correctly **await the completion of scheduled flushes**, preventing premature resolution of pending operations and enhancing the reliability of **workflow serialization**. This **bug fix** prevents potential data integrity issues by guaranteeing proper asynchronous stream handling, and is accompanied by updated tests in `writable-stream.test.ts` to reflect the new flush-on-write behavior.

This commit **resolves a bug** in the **CLI's health check mechanism** by ensuring the `WORKFLOW_LOCAL_BASE_URL` environment variable is correctly recognized, specifically addressing issues encountered with **Astro and Sveltekit** projects. Concurrently, it **enhances debugging capabilities** by introducing an `httpLog` function within the **`world-vercel` package**, which integrates into `makeRequest` to provide detailed HTTP request logging. Furthermore, debug logging is added to the **core runtime's** `getAllWorkflowRunEvents` to track event page loading, collectively improving observability for developers and maintainers.

This commit introduces a **new feature** to the **`world-vercel` package**, specifically enhancing its **event handling subsystem**. It now enables the `payload` of `hook_received` events to be accepted as **references**, offering more flexible and efficient data handling. Concurrently, the underlying API endpoints for event-related operations, such as `getEvent`, `getWorkflowRunEvents`, and `createWorkflowRunEvent`, have been upgraded from version 2 to version 3. This ensures compatibility with the latest API and provides users with greater flexibility in structuring and processing event data.

This commit introduces a **bug fix** to the **core runtime** that prevents failures when attempting to queue or process a workflow run that has already completed. The `workflowEntrypoint` in `packages/core/src/runtime.ts` and the `handleSuspension` logic in `packages/core/src/runtime/suspension-handler.ts` are updated to gracefully handle API responses with **409 (Conflict)** or **410 (Gone)** status codes. By treating these responses as an indication that the workflow is already finished, the system avoids unnecessary errors and improves the robustness of workflow processing, particularly in scenarios involving retries or concurrent operations. This change ensures that the system can proceed without error even if a workflow has already been marked as complete.

This commit introduces significant **new capabilities** and **enhancements** to the **`DurableAgent`**, improving its extensibility, observability, and type safety. It integrates **OpenTelemetry** for detailed tracing of AI model interactions and tool execution, and adds a new `prepareStep` lifecycle hook to allow custom logic before each agent step. Additionally, the commit refines **type inference helpers** for `DurableAgent` configurations, ensures direct passthrough of `LanguageModelV3ToolResultOutput` types, and includes a fix for `supportedUrls` to prevent unintended client-side downloads. These updates provide developers with greater control, better insights into agent behavior, and improved type safety, supported by extensive new tests and example workflows.

This commit **enables End-to-End (E2E) tests for the DurableAgent** within the `packages/core` module. It updates the `package.json` `test:e2e` script to include `e2e-agent.test.ts` and configures the **CI workflow** in `.github/workflows/tests.yml` to pass a `NEXT_CANARY` environment variable. Crucially, the new test file itself includes logic to **conditionally skip these DurableAgent E2E tests** when running against a Next.js canary build, mitigating failures caused by a known external regression. This work is a **test enablement and maintenance** effort, ensuring broader test coverage while gracefully handling environmental incompatibilities.

This commit primarily **fixes** issues related to **Next.js workflow discovery** and **enhances** its reliability, particularly for production builds and e2e testing environments. It introduces eager scanning for workflow directives via `seedDiscoveredFilesFromDirs` in the **Next.js builder** to ensure new workflows are included in the first production build, addressing previous lazy discovery problems. Additionally, it expands the default workflow discovery paths in `withWorkflow` and adds robust error handling to `getWorkflowMetadata` in **core e2e utilities** to guarantee manifest presence for non-local deployments. Finally, it includes **test maintenance** by disabling experimental `DurableAgent` e2e tests to stabilize the CI pipeline. This significantly improves the consistency of **Next.js application deployments** and **e2e test execution**.