tasks.json

{
    // See https://go.microsoft.com/fwlink/?LinkId=733558
    // for the documentation about the tasks.json format
    "version": "2.0.0",
    "tasks": [
        {
            "label": "git grep",
            "type": "shell",
            "command": "git --no-pager grep ${input:gitGrepExpr}",
            "presentation": {
                "panel": "dedicated",
                "clear": true
            },
            "problemMatcher": []
        }
    ],
    "inputs": [
        {
            "id": "gitGrepExpr",
            "description": "git grep expression",
            "type": "promptString"
        }
    ]
}