diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/RegistrationResult.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/RegistrationResult.kt
index 439b4beb41..f1639d2a09 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/RegistrationResult.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/RegistrationResult.kt
@@ -18,13 +18,31 @@ package org.matrix.android.sdk.api.auth.registration
 
 import org.matrix.android.sdk.api.session.Session
 
-// Either a session or an object containing data about registration stages
+/**
+ * Either a session or an object containing data about registration stages
+ */
 sealed class RegistrationResult {
+    /**
+     * The registration is successful, the [Session] is provided
+     */
     data class Success(val session: Session) : RegistrationResult()
+
+    /**
+     * The registration still miss some steps. See [FlowResult] to know the details
+     */
     data class FlowResponse(val flowResult: FlowResult) : RegistrationResult()
 }
 
+/**
+ * Information about the missing and completed [Stage]
+ */
 data class FlowResult(
+        /**
+         * List of missing stages
+         */
         val missingStages: List<Stage>,
+        /**
+         * List of completed stages
+         */
         val completedStages: List<Stage>
 )
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/Stage.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/Stage.kt
index c21b667cf7..ce834b976d 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/Stage.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/registration/Stage.kt
@@ -16,25 +16,40 @@
 
 package org.matrix.android.sdk.api.auth.registration
 
+/**
+ * Registration stages
+ */
 sealed class Stage(open val mandatory: Boolean) {
 
-    // m.login.recaptcha
+    /**
+     * m.login.recaptcha stage
+     */
     data class ReCaptcha(override val mandatory: Boolean, val publicKey: String) : Stage(mandatory)
 
-    // m.login.email.identity
+    /**
+     * m.login.email.identity stage
+     */
     data class Email(override val mandatory: Boolean) : Stage(mandatory)
 
-    // m.login.msisdn
+    /**
+     * m.login.msisdn stage
+     */
     data class Msisdn(override val mandatory: Boolean) : Stage(mandatory)
 
-    // m.login.dummy, can be mandatory if there is no other stages. In this case the account cannot be created by just sending a username
-    // and a password, the dummy stage has to be done
+    /**
+     * m.login.dummy, can be mandatory if there is no other stages. In this case the account cannot be created by just sending a username
+     * and a password, the dummy stage has to be done
+     */
     data class Dummy(override val mandatory: Boolean) : Stage(mandatory)
 
-    // Undocumented yet: m.login.terms
+    /**
+     * Undocumented yet: m.login.terms  stage
+     */
     data class Terms(override val mandatory: Boolean, val policies: TermPolicies) : Stage(mandatory)
 
-    // For unknown stages
+    /**
+     * For unknown stages
+     */
     data class Other(override val mandatory: Boolean, val type: String, val params: Map<*, *>?) : Stage(mandatory)
 }