OpenApi Generator gradle plugin generates new gradle project

Description

Hello!

I'm trying to generate code via OpenAPI Generator Gradle Plugin version 5.1.1
I can't understand behavior of this plugin, it generates new gradle project, but not only kotlin classes

my task configuration is

openApiGenerate {
    //verbose.set(true)
    generatorName.set("kotlin")
    outputDir.set(project.file("${buildDir.name}/generated").absolutePath)
    inputSpec.set(project.file("schema/openapi.json").absolutePath)
    packageName.set("org.camunda.bpm.engine.rest")
    apiPackage.set("org.camunda.bpm.engine.rest.api")
    modelPackage.set("org.camunda.bpm.engine.rest.model")
}

As far as i know, maven plugin generates just classes, not new project
Looks like gradle plugins works as generator cli

Why openapi generator gradle plugin generates new project?

openapi-generator version

5.1.1

OpenAPI declaration file content or url

Command line used for generation

Steps to reproduce

Related issues/PRs

Suggest a fix/enhancement

The report names the Gradle plugin's openApiGenerate configuration, generatorName, outputDir, and inputSpec, but no source files, test, or reproducible specification. Start by reproducing the shown configuration with version 5.1.1 and inspect the plugin's handling of outputDir and project files. Done means determining whether the generated Gradle project is expected, then documenting or correcting that behavior.