[docs] Document argument-based built-in resource commands (set-parameter/delete-parameter)

src/frontend/src/content/docs/reference/cli/commands/aspire-resource.mdx

@@ -112,7 +112,38 @@ When executed without the `--apphost` option, the command:
 
 - **`<command>`**
 
-  The name of the resource command to execute, such as `start`, `stop`, or `restart`.
+  The name of the resource command to execute, such as `start`, `stop`, `restart`, `set-parameter`, or `delete-parameter`.
+
+## Built-in parameter commands
+
+Aspire provides two built-in resource commands for managing parameter resources at runtime. These commands accept named options and can be used non-interactively (for example, in scripts or automation):
+
+- **`set-parameter`** — Set the value of a parameter resource. The legacy name `parameter-set` is also accepted.
+
+  | Option | Description |
+  | --- | --- |
+  | `--value <value>` | The value to assign to the parameter. Required. |
+  | `--save-to-user-secrets` | Save the value to the .NET user secrets store in addition to the running AppHost. Optional; defaults to preserving any existing saved state. |
+
+  ```bash title="Aspire CLI"
+  aspire resource mydb-password set-parameter --value "MyStr0ngP@ssword"
+  aspire resource mydb-password set-parameter --value "MyStr0ngP@ssword" --save-to-user-secrets true
+  ```
+
+- **`delete-parameter`** — Delete the current value of a parameter resource. The legacy name `parameter-delete` is also accepted.
+
+  | Option | Description |
+  | --- | --- |
+  | `--delete-from-user-secrets` | Also remove the value from the .NET user secrets store. Optional. |
+
+  ```bash title="Aspire CLI"
+  aspire resource mydb-password delete-parameter
+  aspire resource mydb-password delete-parameter --delete-from-user-secrets true
+  ```
+
+<Aside type="note">
+The canonical command names changed in Aspire 13.4. `parameter-set` was renamed to `set-parameter` and `parameter-delete` was renamed to `delete-parameter`. The old names are accepted as aliases and continue to work.
+</Aside>
 
 ## Options
 

src/frontend/src/content/docs/whats-new/aspire-13-4.mdx

@@ -22,8 +22,42 @@ We'd love to hear what you think. Drop by [<Icon name="discord" class='d-inline'
 
 This release introduces:
 
+- **Argument-based built-in resource commands** — the `set-parameter` and `delete-parameter` commands now accept named options, enabling non-interactive parameter management from the CLI or automated tooling.
 - …and much more.
 
+## Argument-based built-in resource commands
+
+Built-in resource commands for managing parameter resources now declare structured arguments. Instead of being prompted interactively for input, you can supply values directly as named options on the command line:
+
+```bash title="Aspire CLI — set a parameter value"
+aspire resource mydb-password set-parameter --value "MyStr0ngP@ssword"
+```
+
+```bash title="Aspire CLI — delete a parameter value"
+aspire resource mydb-password delete-parameter --delete-from-user-secrets true
+```
+
+This makes it straightforward to manage parameter values from scripts, CI/CD pipelines, and AI coding agents without requiring interactive prompts. Pass `--help` after the command name to see the available options for any argument-based command:
+
+```bash title="Aspire CLI — show argument help"
+aspire resource mydb-password set-parameter --help
+```
+
+### Command name changes
+
+As part of this improvement, two built-in parameter commands were renamed for consistency with other Aspire CLI commands:
+
+| Old name (still accepted) | New canonical name |
+| --- | --- |
+| `parameter-set` | `set-parameter` |
+| `parameter-delete` | `delete-parameter` |
+
+<Aside type="note">
+The old names (`parameter-set` and `parameter-delete`) are retained as aliases and continue to work. No action is required for existing scripts.
+</Aside>
+
+<LearnMore link="/reference/cli/commands/aspire-resource/#built-in-parameter-commands">Built-in parameter commands</LearnMore>
+
 ## 🆙 Upgrade to Aspire 13.4
 
 <span id="upgrade-to-aspire-13-4"></span>