@get:InputFiles
    abstract val inputSummaries: ConfigurableFileCollection

    @get:OutputFile
    abstract val outputFile: RegularFileProperty

    @TaskAction
    fun summarize() {
        outputFile.get().asFile.run {
            parentFile.mkdirs()
            writeText(summaryString())
        }
    }

    private

task("myOtherTask") {
    val outputFile = newOutputFile()
    doLast { ... }
}
----
=====
====

Now you have to explicitly register `outputFile`, like this:

====
[.multi-language-sample]
=====
.build.gradle
[source, groovy]
----
class MyTask extends DefaultTask {
    @OutputFile // property needs an annotation
    final RegularFileProperty outputFile = project.objects.fileProperty()
}

        def sharedFile = file("output")

        given:
        Task a = task("a", type: AsyncWithOutputFile)
        _ * a.outputFile >> sharedFile
        Task b = task("b", type: AsyncWithOutputFile)
        _ * b.outputFile >> sharedFile

        expect:
        tasksAreNotExecutedInParallel(a, b)
    }

import org.gradle.api.tasks.LocalState
import org.gradle.api.tasks.Nested
import org.gradle.api.tasks.Optional
import org.gradle.api.tasks.OutputDirectories
import org.gradle.api.tasks.OutputDirectory
import org.gradle.api.tasks.OutputFile
import org.gradle.build.event.BuildEventsListenerRegistry
import org.gradle.integtests.fixtures.AbstractIntegrationSpec
import org.gradle.integtests.fixtures.ToBeFixedForConfigurationCache

        assertEquals("test.html", pom.getValue("reporting/plugins[1]/configuration/outputFile"));
        assertEquals(1, ((List<?>) pom.getValue("reporting/plugins[1]/reportSets")).size());
        assertEquals("it", pom.getValue("reporting/plugins[1]/reportSets[1]/id"));
        assertEquals("index.html", pom.getValue("reporting/plugins[1]/reportSets[1]/configuration/outputFile"));

			if file.FileInfo().IsDir() {
				return os.MkdirAll(extractedFilePath, file.Mode())
			}
			outputFile, err := os.OpenFile(extractedFilePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, file.Mode())
			if err != nil {
				return err
			}
			defer outputFile.Close()
			_, err = io.Copy(outputFile, zippedFile)
			return err
		}()
		if err != nil {
			return err
		}
	}
	return nil

| `@link:{javadocPath}/org/gradle/api/tasks/OutputFile.html[OutputFile]`
| `File`*
| A single output file (not directory)

| `@link:{javadocPath}/org/gradle/api/tasks/OutputDirectory.html[OutputDirectory]`
| `File`*
| A single output directory (not file)

Using a reliable, single source of truth, such as a task or shared project property, is better.
In the following modified example, we use a report task defined elsewhere that has the report's location stored in its `outputFile` property:

====
include::sample[dir="snippets/files/copy/kotlin",files="build.gradle.kts[tags=copy-single-file-example-with-task-properties]"]