docs: add MCP guide

.vitepress/config.ts

@@ -64,6 +64,7 @@ export default defineConfig({
         {
           text: 'Guides',
           items: [
+            {text: 'AI Agents (MCP)', link: '/docs/mcp'},
             {text: 'Migrate to 3.x', link: '/docs/migrate-to-3'},
             {text: '(more) Push message examples', link: '/docs/more-pushmsg'},
             {text: 'OpenID Connect', link: '/docs/oidc'},

docs/mcp.md

@@ -0,0 +1,66 @@
+# AI Agents (MCP)
+
+[[toc]]
+
+Gotify provides a [Model Context Protocol](https://modelcontextprotocol.io/) (MCP) endpoint at `/mcp`,
+which lets AI agents such as Claude Code or VS Code Copilot send you push notifications,
+e.g. when a long-running task is done or needs your input.
+
+The endpoint uses the Streamable HTTP transport in stateless mode, so it works behind a reverse proxy
+without any extra configuration.
+
+## Authentication
+
+The endpoint only accepts [application tokens](pushmsg.md). Messages are sent as that application,
+and the agent can't read, delete or manage anything else. Pass the token via:
+
+- the `Authorization: Bearer <apptoken>` header
+- the `X-Gotify-Key: <apptoken>` header
+
+## Client setup
+
+Replace `https://gotify.example.com` with the URL of your Gotify server and `<apptoken>` with an application token.
+
+### Claude Code
+
+```bash
+claude mcp add gotify --transport http https://gotify.example.com/mcp --header "Authorization: Bearer <apptoken>"
+```
+
+### VS Code
+
+Add the server to `.vscode/mcp.json` or your user MCP configuration:
+
+```json
+{
+  "servers": {
+    "gotify": {
+      "type": "http",
+      "url": "https://gotify.example.com/mcp",
+      "headers": {"Authorization": "Bearer <apptoken>"}
+    }
+  }
+}
+```
+
+### Other clients
+
+Add an MCP server with the Streamable HTTP transport, the URL `https://gotify.example.com/mcp`,
+and the `Authorization: Bearer <apptoken>` header.
+
+## The `send_message` tool
+
+The endpoint exposes a single tool `send_message` with the following arguments:
+
+| Argument        | Description                                                                                                      |
+| :-------------- | :--------------------------------------------------------------------------------------------------------------- |
+| `message`       | The message content. Required.                                                                                   |
+| `title`         | The message title. Defaults to the application name.                                                             |
+| `priority`      | The [message priority](priority.md). Defaults to the default priority of the application.                        |
+| `markdown`      | Render the message as Markdown. Sets [`client::display`](msgextras.md#client-display).                           |
+| `click_url`     | A URL to open when the notification is clicked. Sets [`client::notification`](msgextras.md#client-notification). |
+| `big_image_url` | An image to show in the notification. Sets [`client::notification`](msgextras.md#client-notification).           |
+
+## Disabling the endpoint
+
+See [GOTIFY_MCP_ENABLED](config.md#gotify-mcp-enabled).