diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
index 05a403c7..8a7d2f09 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
@@ -7,6 +7,9 @@ import jetbrains.mps.logic.reactor.program.Constraint;
 
 import java.util.List;
 
+/**
+ * Represents a run-time object corresponding to an actual constraint.
+ */
 public interface ConstraintOccurrence {
 
     Constraint constraint();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationFailureException.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationFailureException.java
index 95ed4479..4ea1a3e0 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationFailureException.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationFailureException.java
@@ -3,6 +3,9 @@ package jetbrains.mps.logic.reactor.evaluation;
 /*Generated by MPS */
 
 
+/**
+ * Thrown in case evaluation fails.
+ */
 public class EvaluationFailureException extends RuntimeException {
 
   public EvaluationFailureException(String message) {
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationSession.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationSession.java
index a719edaa..dfd3d6fb 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationSession.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationSession.java
@@ -7,6 +7,13 @@ import jetbrains.mps.logic.reactor.program.*;
 
 import java.util.List;
 
+/**
+ * The starting point to evaluate a program.
+ *
+ * The session is started with {@code newSession}, provided the backend has been initialized.
+ *
+ * The backend is supposed to be provided at startup.
+ */
 public abstract class EvaluationSession {
 
     public static EvaluationSession current() {
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationTrace.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationTrace.java
index 518c16ab..6afd394c 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationTrace.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/EvaluationTrace.java
@@ -3,6 +3,9 @@ package jetbrains.mps.logic.reactor.evaluation;
 /*Generated by MPS */
 
 
+/**
+ * An interface to be implemented by clients wishing to be notified of the events during evaluation.
+ */
 public interface EvaluationTrace {
 
   void activate(ConstraintOccurrence occurrence);
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Instructible.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Instructible.java
index 4d8ac65d..ba09a5f0 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Instructible.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Instructible.java
@@ -2,6 +2,9 @@ package jetbrains.mps.logic.reactor.evaluation;
 
 /*Generated by MPS */
 
+/**
+ * Abstract interface to a predicate.
+ */
 public interface Instructible {
 
     void tell(PredicateInvocation invocation);
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/MatchRule.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/MatchRule.java
index 49ab22a4..541c3305 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/MatchRule.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/MatchRule.java
@@ -4,6 +4,9 @@ package jetbrains.mps.logic.reactor.evaluation;
 
 import jetbrains.mps.logic.reactor.program.Rule;
 
+/**
+ * A binding of a rule and the constraints that matched its head.
+ */
 public interface MatchRule {
 
   Rule rule();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/PredicateInvocation.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/PredicateInvocation.java
index 046584ba..fd3a37ea 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/PredicateInvocation.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/PredicateInvocation.java
@@ -7,6 +7,9 @@ import jetbrains.mps.logic.reactor.program.Predicate;
 
 import java.util.List;
 
+/**
+ * A run-time object representing invocation of a predicate. 
+ */
 public interface PredicateInvocation {
 
     Predicate predicate();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Queryable.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Queryable.java
index f5112b9d..9ebbb80e 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Queryable.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/Queryable.java
@@ -2,6 +2,9 @@ package jetbrains.mps.logic.reactor.evaluation;
 
 /*Generated by MPS */
 
+/**
+ * Abstract interface to a predicate.
+ */
 public interface Queryable extends Instructible {
 
     boolean ask(PredicateInvocation invocation);
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/StoreView.java b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/StoreView.java
index 1a2f5f85..52462756 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/StoreView.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/evaluation/StoreView.java
@@ -3,7 +3,7 @@ package jetbrains.mps.logic.reactor.evaluation;
 import jetbrains.mps.logic.reactor.program.ConstraintSymbol;
 
 /**
- * @author Fedor Isakov
+ * A read-only view on the constraints store.
  */
 public interface StoreView {
 
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/Logical.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/Logical.java
index a4c7bc24..59176467 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/Logical.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/Logical.java
@@ -3,6 +3,11 @@ package jetbrains.mps.logic.reactor.logical;
 /*Generated by MPS */
 
 
+/**
+ * A run-time representation of a logical variable.
+ *
+ * @param <T> the value type
+ */
 public interface Logical<T> {
 
   String name();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalOwner.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalOwner.java
index 40829adb..774b9587 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalOwner.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalOwner.java
@@ -3,6 +3,9 @@ package jetbrains.mps.logic.reactor.logical;
 /*Generated by MPS */
 
 
+/**
+ * An abstract wrapper for a {@link Logical}.
+ */
 public interface LogicalOwner {
 
   Logical<?> logical();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalUnification.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalUnification.java
index a078c2b5..44445011 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalUnification.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/LogicalUnification.java
@@ -4,6 +4,10 @@ package jetbrains.mps.logic.reactor.logical;
 
 import jetbrains.mps.unification.Term;
 
+/**
+ * Not used in the API.
+ * @deprecated
+ */
 public interface LogicalUnification {
 
   <TERM extends Term> TERM asRoot(TERM term);
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/MetaLogical.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/MetaLogical.java
index 148ef5e1..90225b64 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/MetaLogical.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/MetaLogical.java
@@ -3,16 +3,20 @@ package jetbrains.mps.logic.reactor.logical;
 /*Generated by MPS */
 
 
-public class MetaLogical<V> {
+/**
+ * A declaration of a logical variable.  
+ * @param <T> the value type
+ */
+public class MetaLogical<T> {
 
   private static final String WILDCARD = "_";
 
-  public MetaLogical(String name, Class<V> type) {
+  public MetaLogical(String name, Class<T> type) {
     this.name = name;
     this.type = type;
   }
 
-  public MetaLogical(Class<V> type) {
+  public MetaLogical(Class<T> type) {
     this.name = MetaLogical.WILDCARD + System.identityHashCode(this);
     this.type = type;
     this.wildcard = true;
@@ -26,7 +30,7 @@ public class MetaLogical<V> {
     return wildcard;
   }
 
-  public Class<V> type() {
+  public Class<T> type() {
     return type;
   }
 
@@ -36,7 +40,7 @@ public class MetaLogical<V> {
   }
 
   private String name;
-  private Class<V> type;
+  private Class<T> type;
   private boolean wildcard = false;
 
 }
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/MultiMetaLogical.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/MultiMetaLogical.java
index c0a255de..0371f112 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/MultiMetaLogical.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/MultiMetaLogical.java
@@ -5,9 +5,13 @@ package jetbrains.mps.logic.reactor.logical;
 import java.util.List;
 import java.util.ArrayList;
 
-public class MultiMetaLogical<V> extends MetaLogical<V> {
+/**
+ * A declaration of a logical variable with index. 
+ * @param <T>
+ */
+public class MultiMetaLogical<T> extends MetaLogical<T> {
 
-  public MultiMetaLogical(String name, Class<V> type, int cardinality) {
+  public MultiMetaLogical(String name, Class<T> type, int cardinality) {
     super(name, type);
     this.cardinality = cardinality;
     init();
@@ -17,7 +21,7 @@ public class MultiMetaLogical<V> extends MetaLogical<V> {
     return cardinality;
   }
 
-  public MetaLogical<V> logicalAt(int idx) {
+  public MetaLogical<T> logicalAt(int idx) {
     return metaLogicals.get(idx);
   }
 
@@ -28,10 +32,10 @@ public class MultiMetaLogical<V> extends MetaLogical<V> {
 
   private void init() {
     for (int i = 0; i < cardinality; i++) {
-      metaLogicals.add(new MetaLogical<V>(name() + "_" + (i + 1), type()));
+      metaLogicals.add(new MetaLogical<T>(name() + "_" + (i + 1), type()));
     }
   }
 
   private int cardinality;
-  private List<MetaLogical<V>> metaLogicals = new ArrayList<MetaLogical<V>>();
+  private List<MetaLogical<T>> metaLogicals = new ArrayList<MetaLogical<T>>();
 }
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/logical/SolverLogical.java b/reactor/API/src/jetbrains/mps/logic/reactor/logical/SolverLogical.java
index 7f93f070..e244e98f 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/logical/SolverLogical.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/logical/SolverLogical.java
@@ -3,6 +3,11 @@ package jetbrains.mps.logic.reactor.logical;
 /*Generated by MPS */
 
 
+/**
+ * A logical variable that can be joined with another variable to produce a union.
+ *
+ * @param <T> the value type
+ */
 public interface SolverLogical<T> extends Logical<T> {
 
   /**
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/AndItem.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/AndItem.java
index 5e414398..46e1fd71 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/AndItem.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/AndItem.java
@@ -4,6 +4,9 @@ package jetbrains.mps.logic.reactor.program;
 
 import java.util.List;
 
+/**
+ *  An abstract conjunct. 
+ */
 public interface AndItem {
 
   Symbol symbol();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Constraint.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Constraint.java
index 0f68c9d0..2bb1e348 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Constraint.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/Constraint.java
@@ -7,7 +7,7 @@ import java.util.Collection;
 import jetbrains.mps.logic.reactor.logical.LogicalContext;
 
 /**
- * A constraint provided by a handler. Can only be told.
+ * A constraint provided by a handler.
  */
 public interface Constraint extends AndItem {
 
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Handler.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Handler.java
index 9bad4740..f00653ac 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Handler.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/Handler.java
@@ -1,7 +1,10 @@
 package jetbrains.mps.logic.reactor.program;
 
 /**
- * @author Fedor Isakov
+ *  A handler is a container of rules.
+ *
+ *  If the {@code primarySymbols} is a non-empty collection, only constraints with these symbols are processed
+ *  by this handler.
  */
 public abstract class Handler {
 
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Program.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Program.java
index 95b88a6a..577d5c10 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Program.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/Program.java
@@ -6,6 +6,9 @@ import jetbrains.mps.logic.reactor.logical.LogicalContext;
 
 import java.util.List;
 
+/**
+ * A collection of handlers that constitute a constraint rules program. 
+ */
 public abstract class Program {
 
     public abstract String name();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Rule.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Rule.java
index 6ac9ccbc..713e4158 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Rule.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/Rule.java
@@ -3,6 +3,9 @@ package jetbrains.mps.logic.reactor.program;
 /*Generated by MPS */
 
 
+/**
+ * A constraint rule description.
+ */
 public abstract class Rule {
 
   public abstract Rule.Kind kind();
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Solver.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Solver.java
deleted file mode 100644
index 1cd71896..00000000
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Solver.java
+++ /dev/null
@@ -1,9 +0,0 @@
-package jetbrains.mps.logic.reactor.program;
-
-/*Generated by MPS */
-
-public interface Solver {
-
-
-
-}
diff --git a/reactor/API/src/jetbrains/mps/logic/reactor/program/Symbol.java b/reactor/API/src/jetbrains/mps/logic/reactor/program/Symbol.java
index 56abe5c1..dc13bf4d 100644
--- a/reactor/API/src/jetbrains/mps/logic/reactor/program/Symbol.java
+++ b/reactor/API/src/jetbrains/mps/logic/reactor/program/Symbol.java
@@ -3,6 +3,9 @@ package jetbrains.mps.logic.reactor.program;
 /*Generated by MPS */
 
 
+/**
+ * A symbol used by both constraints and predicates. Is uniquely identified by id and arity.
+ */
 public abstract class Symbol {
 
   protected Symbol(String id, int arity) {