---
uid: Uno.UI.CommonIssues.AIAgents
---

# Issues related to AI Agents

## `dotnet dnx` is not a valid command

The getting started for Claude, Codex, and Copilot CLI uses `dotnet dnx`, which requires the **.NET 10 SDK or newer**. On older SDKs, `dotnet dnx` reports a "command not found" error.

If you want to use the App MCP with an older SDK, install the Dev Server as a global tool and replace `dotnet dnx -y uno.devserver` with `uno-devserver` in the commands and config files:

```bash
dotnet tool install -g uno.devserver
```

## The App MCP does not appear in Visual Studio

1. Open the `.vs/mcp.json` file in Visual Studio. It is located in your solution's root directory.
2. Verify that the Uno MCP server entry is present:

    ```json
    "uno": {
      "url": "https://mcp.platform.uno/v1"
    }
    ```

3. If the entry is missing, add it to the `.vs/mcp.json` file and restart Visual Studio.
4. If the entry exists but the server shows as disconnected, click on "Reconnect" in the file editor:

![Visual Studio MCP reconnect in mcp.json](Assets/vs-mcp-reconnect.png)

The Uno App MCP should now appear in the list of MCPs in Visual Studio.

## The App MCP turns red in Visual Studio 2022/2026

In Visual Studio, the App MCP might turn red on some occasions. To fix this issue, click on the three dots on the right and select `Reload`.

## The uno-app MCP failed to start

The Uno Platform App MCP may fail to start in Claude/Codex/Copilot CLI when it is started in a folder that does not contain an Uno Platform project.

To fix this issue, change directories to a folder that contains the `.sln` or `.slnx` file of your project.

## Diagnosing Dev Server issues

> [!TIP]
> When the App MCP fails to start, run `uno-devserver disco` from your solution directory.
> Check that **hostPath** is resolved and that there are no **errors**. Pass `--json` for machine-readable output.
> See [Diagnostics (disco)](xref:Uno.Features.DevServerDisco) for a full guide.