diff --git a/launch/interface/src/main/java/xsbti/Launcher.java b/launch/interface/src/main/java/xsbti/Launcher.java
index 8f83f1971..30f30e3ef 100644
--- a/launch/interface/src/main/java/xsbti/Launcher.java
+++ b/launch/interface/src/main/java/xsbti/Launcher.java
@@ -8,15 +8,52 @@ public interface Launcher
 	public ScalaProvider getScala(String version);
 	public ScalaProvider getScala(String version, String reason);
 	public ScalaProvider getScala(String version, String reason, String scalaOrg);
+	/**
+	 * returns an `AppProvider` which is able to resolve an application
+	 * and instantiate its `xsbti.Main` in a new classloader.
+	 * See [AppProvider] for more details.
+	 * @param id  The artifact coordinates of the application.
+	 * @param version The version to resolve
+	 */
 	public AppProvider app(ApplicationID id, String version);
+	/**
+	 * This returns the "top" classloader for a launched application.   This classlaoder
+	 * lives somewhere *above* that used for the application.   This classloader
+	 * is used for doing any sort of JNA/native library loads so that downstream
+	 * loaders can share native libraries rather than run into "load-once" restrictions.
+	 */
 	public ClassLoader topLoader();
+	/**
+	 * Return the global lock for interacting with the file system.
+	 *
+	 * A mechanism to do file-based locking correctly on the JVM.  See
+	 * the [[GlobalLock]] class for more details.
+	 */
 	public GlobalLock globalLock();
+	/** Value of the `sbt.boot.dir` property, or the default
+	 *  boot configuration defined in `boot.directory`.
+	 */
 	public File bootDirectory();
-  /** Configured launcher repositories. */
+	/** Configured launcher repositories.  These repositories
+	 *  are the same ones used to load the launcher.
+	 */
 	public xsbti.Repository[] ivyRepositories();
-	/** The user has configured the launcher with the only repositories it wants to use for this applciation. */
+	/** The user has configured the launcher with the only repositories
+	 * it wants to use for this applciation.
+	 */
 	public boolean isOverrideRepositories();
-	// null if none set
+	/**
+	 * The value of `ivy.ivy-home` of the boot properties file.
+	 * This defaults to the `sbt.ivy.home` property, or `~/.ivy2`.
+	 * Use this setting in an application when using Ivy to resolve
+	 * more artifacts.
+	 *
+	 * @returns a file, or null if not set.
+	 */
 	public File ivyHome();
+	/** An array of the checksums that should be checked when retreiving artifacts.
+	 *  Configured via the the `ivy.checksums` section of the boot configuration.
+	 *  Defaults to sha1, md5 or the value of the `sbt.checksums` property.
+	 */
 	public String[] checksums();
 }