Target class [mcp.registrar] does not exist.

[adamjsturge]

When I tried to go through and setup my application I get Target class [mcp.registrar] does not exist.

The setup guide was a little confusing.

I published my assets, made the routes/mcp.php made my first tool with

use PhpMcp\Laravel\Facades\Mcp;
Mcp::tool

I haven't touched the default config. I tried adding PhpMcp\Laravel\McpServiceProvider::class, to providers which it's unclear if needed.

Also I had to do

        $middleware->validateCsrfTokens(except: [
            env('MCP_HTTP_INTEGRATED_ROUTE_PREFIX', 'mcp').'/message',
        ]);

in app.php since config was apparently not ready yet.

Do we know why my mcp keeps crashing on

[TheWayneSwart]

I don't think those routes are correct. This is typically what I use:

use App\Mcp\Tools\MyToolClass;
use PhpMcp\Laravel\Facades\Mcp;

Mcp::tool([MyToolClass::class, 'test']);

And then the class containing the tool should be something like this:

namespace App\Mcp\Tools;

use PhpMcp\Attributes\McpTool;
use PhpMcp\Attributes\McpResource;

class MyToolClass
{
    #[McpTool(name: 'test')]
    public function test(string $message): string
    {
        return "Discovered echo: {$message}";
    }
}

I hope this helps you.

[CodeWithKyrian]

Hey @adamjsturge, just a heads-up that any issues with the ServiceProvider have been resolved in v2.1.0, so you can go ahead and update.

You’re also right about the CSRF config not being available at that point in the request lifecycle. The docs have now been updated to reflect that (PR #8), so the recommendation is to just use /mcp/message directly.

Also, the suggestions from @TheWayneSwart are spot on ... just one thing to clarify: if you’re defining tools via the mcp.php route file, then there’s no need to use the attribute. The attribute-based discovery is really just for cases where you don’t want to manually register tools in the routes file, in which case the system picks them up automatically based on the attribute. Hope that clears things up!