docs(dsh): say that an installed plugin starts off and must be switched on

Found while demonstrating the install through Discover: until the switch and
both components read Running there is no reasonix tool, and the model falls
back to running reasonix -p in its own shell, which only looks like a
delegation.

docs/DSH.md

@@ -67,6 +67,15 @@ dsh plugin --profile <profile> add github:esengine/DeepSeek-Reasonix#path:/integ
 
 The bundle pins `@deepseek-ai/dsh-subagent-acp` and `dsh` to the same version (`0.2.1-rc.2` today) and uses `permission: reject`. Change the policy in your own `cordis.patch.yml`, never in the package.
 
+## After installing: switch it on
+
+An installed plugin starts **off**. Open its page in the DSH Web UI and turn its switch on.
+
+- The switch and both components (the provider and the `reasonix` tool) must read Running.
+- Turning the switch on in a running `dsh web` is enough: the next new session has the `reasonix` tool (observed on `dsh` 0.2.1-rc.2, 2026-10-18). Restart `dsh` only if it is still missing.
+- While it is off the model has no `reasonix` tool and may run `reasonix -p` in its own shell instead.
+- That looks like a delegation and is not one: there is no subagent, no `reasonix` tool call, and no permission policy applies.
+
 ## Finding it in Discover
 
 DSH ships an optional "Custom plugin markets" feature with no default index; a user adds index URLs themselves. This repository publishes one:

integrations/dsh-plugin/README.md

@@ -26,6 +26,14 @@ dsh plugin --profile <profile> add github:esengine/DeepSeek-Reasonix#path:/integ
 
 The package is not on npm; `pnpm` installs the `integrations/dsh-plugin` subdirectory of this repository (the `path:` selector, see [pnpm package sources](https://pnpm.io/package-sources)).
 
+## After installing: switch it on
+
+An installed plugin starts **off**. Open its page in the DSH Web UI and turn the switch on.
+
+- The switch and both components must read Running. Turning it on in a running `dsh web` is enough: the next new session has the `reasonix` tool (observed on `dsh` 0.2.1-rc.2). Restart `dsh` only if it is still missing.
+- While it is off the model may run `reasonix -p` in its own shell.
+- That looks like a delegation and is not one: there is no subagent, and the permission policy below does not apply.
+
 ## What it changes
 
 | Row | Effect |
@@ -66,6 +74,14 @@ dsh plugin --profile <profile> add github:esengine/DeepSeek-Reasonix#path:/integ
 
 包不在 npm 上：`pnpm` 通过 `path:` 选择器安装本仓库的 `integrations/dsh-plugin` 子目录（见 [pnpm package sources](https://pnpm.io/package-sources)）。
 
+**安装后：打开开关**
+
+插件装好后默认是“关闭”的。到 DSH Web 界面的插件页打开它的开关。
+
+- 开关和两个组件都显示 Running 才算生效。在运行中的 `dsh web` 里直接打开就够了，下一个新会话里就有 `reasonix` 工具（在 `dsh` 0.2.1-rc.2 上实测）；仍然没有再重启 `dsh`。
+- 没打开时，模型可能改在自己的 shell 里直接运行 `reasonix -p`。
+- 这看起来像委派，其实不是：没有子智能体，下面的权限策略也不起作用。
+
 **权限**
 
 - 默认 `permission: reject`：Reasonix 弹出的每个审批卡都会被拒绝，子智能体只能读和调研，不能写文件或执行需要批准的命令。