fix: pass rootDirectory in projectSettings for monorepo deployments

README.md

@@ -73,7 +73,8 @@ These inputs use the `@vercel/client` API directly instead of the CLI. They are
 | build-env                  |    No    |           | Build-time environment variables (`KEY=VALUE` per line)            |
 | regions                    |    No    |           | Deployment regions, comma-separated (e.g. `iad1,sfo1`)            |
 | archive                    |    No    |           | Upload format: `tgz` for compressed archive                       |
-| root-directory             |    No    |           | Root directory of the project relative to the repository root      |
+| root-directory             |    No    |           | Root directory of the project relative to the repository root. When set, Vercel builds from this directory instead of the repo root. |
+| source-files-outside-root-directory |    No    | `false`   | Set to `true` when source files exist outside the root directory (e.g. monorepos with shared packages). Tells Vercel to look for dependencies beyond the root directory. |
 | auto-assign-custom-domains |    No    | `true`    | Automatically assign custom domains to this deployment             |
 | custom-environment         |    No    |           | Custom environment slug or ID                                      |
 | public                     |    No    | `false`   | Make deployment source publicly accessible                         |
@@ -449,6 +450,22 @@ These inputs are only available with API-based deployment (when `vercel-args` is
 - `custom-environment` — Custom environment slug or ID
 - `with-cache` — Retain build cache from previous deployments
 - `vercel-output-dir` — Directory containing prebuilt output (only relevant when `prebuilt: true`)
+- `source-files-outside-root-directory` — Enable monorepo support (default: `false`)
+
+### Monorepo Example
+
+For monorepos, use `root-directory` to tell Vercel which app to build and `source-files-outside-root-directory` to allow Vercel to resolve dependencies outside the root directory (e.g. shared packages):
+
+```yaml
+- uses: amondnet/vercel-action@v42
+  with:
+    vercel-token: ${{ secrets.VERCEL_TOKEN }}
+    vercel-org-id: ${{ secrets.ORG_ID }}
+    vercel-project-id: ${{ secrets.PROJECT_ID }}
+    root-directory: apps/web
+    source-files-outside-root-directory: true
+    target: production
+```
 
 ### Deprecated Inputs
 

action.yml

@@ -115,6 +115,14 @@ inputs:
     required: false
     description: 'Retain build cache from previous deployments (default: false).'
     default: 'false'
+  source-files-outside-root-directory:
+    required: false
+    description: 'Indicates if there are source files outside of the root directory, typically used for monorepos (default: false).'
+    default: 'false'
+  node-version:
+    required: false
+    description: 'Node.js version for the deployment. Must be one of "24.x", "22.x", "20.x". When unset, falls back to package.json engines.node.'
+    default: ''
 
 outputs:
   preview-url:

dist/__tests__/helpers.d.ts

@@ -0,0 +1,3 @@
+import type { ActionConfig, DeploymentContext } from '../types';
+export declare function createConfig(overrides?: Partial<ActionConfig>): ActionConfig;
+export declare function createDeployContext(overrides?: Partial<DeploymentContext>): DeploymentContext;