Malte Ubl

This commit introduces **workflow serialization support** for the **`Sandbox` and `Command` classes** within the `@vercel/sandbox` package, enabling these objects to be passed and rehydrated across different steps of a workflow. This **new capability** allows for more complex, stateful interactions with Vercel Sandboxes in a workflow environment, including lazy API client initialization for serialized objects. A comprehensive **`workflow-code-runner` example** is added, showcasing an AI-driven code generation and execution flow that leverages this serialization to manage sandbox interactions across multiple workflow steps. This significantly enhances the interoperability and power of Vercel Sandboxes when integrated with workflow systems.

This commit introduces a **new type-checking system for documentation code samples**, significantly enhancing the reliability of the project's guides and READMEs. It adds a dedicated `docs-typecheck` package responsible for extracting code, inferring imports, and performing TypeScript checks. A new **GitHub Actions workflow** (`docs-typecheck.yml`) automates this process, and numerous **`.mdx` and `.md` documentation files** are updated to either fix type errors or use `@skip-typecheck` directives. This **new capability** ensures that all code examples remain accurate and functional, improving the overall user experience and preventing outdated or incorrect snippets. It establishes a continuous integration check for documentation integrity.

This commit **restores** the previously removed **agent sitemap generation** functionality for the documentation site, addressing an accidental deletion. It introduces a new route, `docs/app/sitemap.md/route.ts`, to **dynamically generate a markdown sitemap** of all documentation pages, enhancing discoverability. Furthermore, this change significantly **improves the documentation site's SEO** by implementing proper **canonical and alternate URLs** across all pages, utilizing `metadataBase` in `docs/app/layout.tsx` and `generatePageMetadata` in `docs/components/geistdocs/docs-page.tsx`. The `docs/app/llms.mdx/[[...slug]]/route.ts` is also updated to append a sitemap link to LLM documentation responses. This is a critical **feature reinstatement** and **SEO enhancement** for the **documentation platform**.

This commit **enables proper serving of LLMs to agents** and **improves their navigation capabilities** within the documentation. It includes a **bug fix** in the **LLM serving infrastructure** by **refactoring Next.js rewrite rules** in `next.config.mjs` to correctly handle `Accept` headers and ensure proper content delivery for LLM requests, specifically addressing issues with Claude. Concurrently, a **new feature** introduces a **dynamic markdown sitemap** generated by `docs/app/docs/sitemap.md/route.ts`, providing LLMs with an efficient index to discover pages. This sitemap is then made readily accessible by **appending a link to it at the bottom of every markdown page** served to LLMs via `docs/app/llms.mdx/[[...slug]]/route.ts`, significantly enhancing agent autonomy in content exploration.

This commit implements **SEO improvements** across the **documentation site** by optimizing metadata for better search engine visibility. It updates the homepage (`docs/app/(home)/page.tsx`) with a more specific title and canonical URL. For all documentation pages (`docs/app/docs/[[...slug]]/page.tsx`), the `generateMetadata` function now consistently appends ' - Workflow DevKit' to titles and includes canonical URLs. Additionally, a global `metadataBase` URL is added to the root layout (`docs/app/layout.tsx`) to ensure consistent and accurate metadata generation throughout the site.

This commit introduces a **critical fix** to the **`@vercel/functions` package**, addressing an issue where database connection management logic was inadvertently executing during build processes. It **strengthens the runtime environment check** for the `attachDatabasePool` feature by modifying the `waitUntilIdleTimeout` function in `packages/functions/src/db-connections/index.ts` to explicitly verify `process.env.VERCEL_REGION`. This ensures the database pool attachment and idle timeout mechanisms **only activate within an actual Vercel function environment**, preventing unnecessary operations and improving build efficiency. The change enhances the **robustness and correct behavior** of functions utilizing database connections, accompanied by updated documentation and unit tests.

This commit **refines error handling** within the **Next.js server and middleware launchers** by **removing explicit `process.exit(1)` calls**. Specifically, the `serve` functions in `packages/next/src/middleware-launcher.ts` and `packages/next/src/server-launcher.ts` no longer force process termination on unhandled exceptions. This **bug fix** allows errors to properly bubble up to global error handling facilities, significantly improving the **application's resilience** and ability to remain operational and serve other requests even when unexpected issues occur.

This commit introduces a **new feature** to the **`@vercel/firewall` package**, enhancing its **rate-limiting capabilities**. It now automatically forwards Vercel authentication cookies (`_vercel_jwt`) when present, ensuring authenticated users are correctly rate-limited. Crucially, it refactors header discovery to use a **global request context** instead of `next/headers`, thereby enabling **support for all frameworks** and improving the module's versatility. This change ensures rate limiting functions correctly for authenticated Vercel users across various environments, with new end-to-end tests validating the forwarding of the auth cookie and the global context header discovery.

This commit **stabilizes the `attachDatabasePool` API** within the **`@vercel/functions` package**, promoting it from an experimental feature to a stable one. It involves **refactoring** the internal implementation by renaming `experimental_attachDatabasePool` to `attachDatabasePool` and providing a deprecated alias for the old name to ensure backward compatibility. The **documentation** for the database connection utilities has been updated to reflect this stability, marking the experimental version as deprecated. This change allows developers to use the database pooling feature with confidence, impacting any projects utilizing `@vercel/functions` for database connections.

This commit introduces a **fix** to the **database connection management** system, making the `attachDatabasePool` mechanism **inert in local development environments**. Specifically, the `waitUntilIdleTimeout` function within the `db-connections` module now checks for the `VERCEL_URL` environment variable, disabling its functionality when not present. This change prevents issues in local development where there is no request context or `waitUntil` functionality, thereby **improving the local development experience** for functions utilizing database pools. Documentation for `experimental_attachDatabasePool` has been updated in `packages/functions/docs/modules/index.md`, and unit tests in `packages/functions/test/unit/db-connections/index.test.ts` were adjusted to validate this new inert behavior.

This commit introduces the **experimental `experimental_attachDatabasePool` function** to the **`@vercel/functions`** package, providing a **new capability** for managing database connection pool lifetimes in serverless environments. It establishes a new `db-connections` module, including core logic for attaching and handling various database driver types, alongside type assertions and comprehensive unit tests. This feature aims to optimize database interactions by enabling efficient connection reuse for serverless functions, with initial documentation and package exports now available.

This commit **updates the metadata description** for the **`@vercel/firewall` package**, enhancing its clarity for consumers. Specifically, it modifies the `description` field within `packages/firewall/package.json` to reflect a more accurate or updated summary of the package's functionality. This **documentation update** improves the discoverability and understanding of the package, and also includes a new changeset file (`.changeset/nine-spoons-tan.md`) to document this patch-level change for future releases.

This commit **stabilizes the `checkRateLimit` API** within the **`@vercel/firewall` package**, promoting it from an unstable preview to a production-ready function. It **renames `unstable_checkRateLimit` to `checkRateLimit`** in `packages/firewall/src/rate-limit.ts` and updates all associated **documentation** and **tests** to reflect this change. A backward-compatible export for the old name is also added, ensuring a smooth transition for existing users. This **API stabilization** signifies the maturity of the rate limiting feature, allowing developers to integrate it with confidence.

This commit **fixes module resolution** for the **`@vercel/mcp-adapter` package** by updating its `package.json` exports. It reconfigures the `require` field to correctly point to the generated `.js` files instead of `.cjs` files, ensuring proper module loading and preventing potential import errors. This **maintenance update** also includes adding new codeowners for the `mcp-adapter` directory to improve project maintainability and documents the change with a new changeset. The change primarily impacts how the `mcp-adapter` package is consumed in environments using `require`, ensuring it references the correct build artifacts.