diff --git a/website/.vitepress/config.ts b/website/.vitepress/config.ts
index 24c675f1..db44f510 100644
--- a/website/.vitepress/config.ts
+++ b/website/.vitepress/config.ts
@@ -302,6 +302,10 @@ export default defineConfig({
             {
               text: 'Remote Taskfiles (#1317)',
               link: '/docs/experiments/remote-taskfiles'
+            },
+            {
+              text: 'Scoped Taskfiles',
+              link: '/docs/experiments/scoped-taskfiles'
             }
           ]
         },
diff --git a/website/src/docs/experiments/scoped-taskfiles.md b/website/src/docs/experiments/scoped-taskfiles.md
new file mode 100644
index 00000000..7cee72e8
--- /dev/null
+++ b/website/src/docs/experiments/scoped-taskfiles.md
@@ -0,0 +1,201 @@
+---
+title: 'Scoped Taskfiles'
+description:
+  Experiment for variable isolation and env namespace in included Taskfiles
+outline: deep
+---
+
+# Scoped Taskfiles
+
+::: warning
+
+All experimental features are subject to breaking changes and/or removal _at any
+time_. We strongly recommend that you do not use these features in a production
+environment. They are intended for testing and feedback only.
+
+:::
+
+::: danger
+
+This experiment breaks the following functionality:
+
+- **Environment variables are no longer available at root level in templates**
+  - Before: <span v-pre>`{{.PATH}}`</span>, <span v-pre>`{{.MY_ENV}}`</span>
+  - After: <span v-pre>`{{.env.PATH}}`</span>,
+    <span v-pre>`{{.env.MY_ENV}}`</span>
+- **Variables from sibling includes are no longer visible**
+  - Include A cannot access variables defined in Include B
+  - Each include only sees: root vars + its own vars + parent vars
+
+:::
+
+::: info
+
+To enable this experiment, set the environment variable:
+`TASK_X_SCOPED_TASKFILES=1`. Check out
+[our guide to enabling experiments](./index.md#enabling-experiments) for more
+information.
+
+:::
+
+This experiment introduces two major changes to how variables work in Task:
+
+1. **Environment namespace**: Environment variables (both OS and Taskfile `env:`
+   sections) are moved to a dedicated <span v-pre>`{{.env.XXX}}`</span>
+   namespace, separating them from regular variables
+2. **Variable scoping**: Variables defined in included Taskfiles are isolated -
+   sibling includes cannot see each other's variables
+
+## Environment Namespace
+
+With this experiment enabled, environment variables are no longer mixed with
+regular variables at the template root level. Instead, they are accessible
+through the <span v-pre>`{{.env.XXX}}`</span> namespace.
+
+### Comparison Table
+
+| Template                                        | Legacy | SCOPED_TASKFILES          |
+| ----------------------------------------------- | ------ | ------------------------- |
+| <span v-pre>`{{.MY_VAR}}`</span> (from `vars:`) | Works  | Works                     |
+| <span v-pre>`{{.MY_ENV}}`</span> (from `env:`)  | Works  | `<no value>`              |
+| <span v-pre>`{{.env.MY_ENV}}`</span>            | -      | Works                     |
+| <span v-pre>`{{.PATH}}`</span> (OS)             | Works  | `<no value>`              |
+| <span v-pre>`{{.env.PATH}}`</span> (OS)         | -      | Works                     |
+| <span v-pre>`{{.TASK}}`</span> (special)        | Works  | Works (stays at root)     |
+
+### Example
+
+```yaml
+version: '3'
+
+env:
+  DB_HOST: localhost
+
+vars:
+  DB_NAME: mydb
+
+tasks:
+  show:
+    cmds:
+      # Access Taskfile env: section
+      - echo "Host: {{.env.DB_HOST}}"
+
+      # Access regular vars (unchanged)
+      - echo "Name: {{.DB_NAME}}"
+
+      # Access OS environment variables
+      - echo "Path: {{.env.PATH}}"
+
+      # Special variables stay at root level
+      - echo "Task: {{.TASK}}"
+```
+
+## Variable Scoping
+
+Variables defined in included Taskfiles are now isolated from each other.
+Sibling includes cannot access each other's variables, but child includes can
+still inherit variables from their parent.
+
+### Example
+
+```yaml
+# Taskfile.yml
+version: '3'
+
+vars:
+  ROOT_VAR: from_root
+
+includes:
+  api: ./api
+  web: ./web
+```
+
+```yaml
+# api/Taskfile.yml
+version: '3'
+
+vars:
+  API_VAR: from_api
+
+tasks:
+  show:
+    cmds:
+      # Inherited from root - works
+      - echo "ROOT_VAR={{.ROOT_VAR}}"
+
+      # Own variable - works
+      - echo "API_VAR={{.API_VAR}}"
+
+      # From sibling include - NOT visible
+      - echo "WEB_VAR={{.WEB_VAR}}"
+```
+
+```yaml
+# web/Taskfile.yml
+version: '3'
+
+vars:
+  WEB_VAR: from_web
+
+tasks:
+  show:
+    cmds:
+      # Inherited from root - works
+      - echo "ROOT_VAR={{.ROOT_VAR}}"
+
+      # Own variable - works
+      - echo "WEB_VAR={{.WEB_VAR}}"
+
+      # From sibling include - NOT visible
+      - echo "API_VAR={{.API_VAR}}"
+```
+
+## CLI Variables Priority
+
+With this experiment, CLI variables (passed as `task foo VAR=value`) have the
+highest priority and will override task-level variables.
+
+```yaml
+version: '3'
+
+tasks:
+  greet:
+    vars:
+      NAME: from_task
+    cmds:
+      - echo "Hello {{.NAME}}"
+```
+
+```bash
+# CLI vars now override task vars
+TASK_X_SCOPED_TASKFILES=1 task greet NAME=cli
+# Output: Hello cli
+```
+
+## Migration Guide
+
+To migrate your Taskfiles to use this experiment:
+
+1. **Update environment variable references** in your templates:
+
+   - <span v-pre>`{{.PATH}}`</span> becomes
+     <span v-pre>`{{.env.PATH}}`</span>
+   - <span v-pre>`{{.HOME}}`</span> becomes
+     <span v-pre>`{{.env.HOME}}`</span>
+   - <span v-pre>`{{.MY_TASKFILE_ENV}}`</span> becomes
+     <span v-pre>`{{.env.MY_TASKFILE_ENV}}`</span>
+
+2. **Variables in `vars:` sections remain unchanged**:
+
+   - <span v-pre>`{{.MY_VAR}}`</span> still works the same way
+
+3. **Special variables stay at root level**:
+
+   - <span v-pre>`{{.TASK}}`</span>, <span v-pre>`{{.ROOT_DIR}}`</span>,
+     <span v-pre>`{{.TASKFILE}}`</span>, <span v-pre>`{{.TASKFILE_DIR}}`</span>,
+     etc.
+
+4. **Review cross-include variable dependencies**:
+   - If your included Taskfiles rely on variables from sibling includes, you'll
+     need to either move those variables to the root Taskfile or pass them
+     explicitly via the `vars:` attribute in the `includes:` section.