How to perform unit testing in "GET" api in laravel

I am not able to understand how can i write unit test for my get api. my url => /api/admin/agents?roleId=3

This is reponse when i am passing correct role id:

{
    "message": null,
    "data": {
        "items": [
            {
                "id": 4,
                "firstName": "Himanshu",
                "lastName": "Sharma",
                "phone": null,          
            }
        ],
        "page": 1,
        "total": 3,
        "pages": 1,
        "perpage": 15
    },
    "type": null
}

this is when i am passing any invalid role id

{
    "message": null,
    "data": {
        "items": [],
        "page": 1,
        "total": 0,
        "pages": 1,
        "perpage": 15
    },
    "type": null
}

mycode

public function test_get_api_for_agent()
    {
        $admin_login_response=$this->json('POST','/api/authenticate',['email'=>'abc@luezoid.com', 'password' => 'password']);
       
        $token= [
            'authorization' => 'Bearer '.$admin_login_response['data']['token']
        ];

        $seller_block_patch_reponse = $this->withHeaders($token)->json('GET','api/admin/agents?roleId=3');
        $seller_block_patch_reponse
        ->assertStatus(200)
        ->assertJson([
            'data' => ''
        ]); 
    }

via Chebli Mohamed