diff --git a/src/api/verify.js b/src/api/verify.js
index 2f174c8..56652ce 100644
--- a/src/api/verify.js
+++ b/src/api/verify.js
@@ -1,3 +1,11 @@
 import _verify from '../core/_verify.js';
+/**
+ * Verify that satisfiability of the input instance can be derived from the
+ * input certificate.
+ *
+ * @param {ParitiesInstance|SignsInstance|KeysInstance} instance
+ * @param {number[]} certificate
+ * @return {boolean}
+ */
 const verify = ({clauses}, certificate) => _verify(clauses, certificate);
 export default verify;
diff --git a/src/core/_verify.js b/src/core/_verify.js
index 857fd9f..0d82ad2 100644
--- a/src/core/_verify.js
+++ b/src/core/_verify.js
@@ -3,9 +3,9 @@
  * of clauses. The list of clauses and the assignment vector are in parity
  * format.
  *
- * @param {Iterable} clauses The clauses in parity format.
- * @param {Array} assignment The assignment vector in parity format.
- * @returns {Boolean} Whether the assignment satisfies the k-CNF formula
+ * @param {number[][]} clauses The clauses in parity format.
+ * @param {number[]} assignment The assignment vector in parity format.
+ * @returns {boolean} Whether the assignment satisfies the k-CNF formula
  * represented by the list of clauses.
  */
 export default function _verify(clauses, assignment) {
diff --git a/src/core/convert/KeysInstance.js b/src/core/convert/KeysInstance.js
index 983976e..d289fea 100644
--- a/src/core/convert/KeysInstance.js
+++ b/src/core/convert/KeysInstance.js
@@ -1,5 +1,9 @@
 import _certificate_to_keys from './_certificate_to_keys.js';
 
+/**
+ * Maintains a mapping between variable names and a parity
+ * representation of the instance.
+ */
 export default class KeysInstance {
 	/**
 	 * Constructor.
diff --git a/src/core/convert/ParitiesInstance.js b/src/core/convert/ParitiesInstance.js
index 4680c56..8909b39 100644
--- a/src/core/convert/ParitiesInstance.js
+++ b/src/core/convert/ParitiesInstance.js
@@ -1,5 +1,8 @@
 import _count from './_count.js';
 
+/**
+ * Holds all properties of a k-CNF SAT instance in parity format.
+ */
 export default class ParitiesInstance {
 	/**
 	 * Clauses are in parity format.
diff --git a/src/core/convert/SignsInstance.js b/src/core/convert/SignsInstance.js
index b164833..d6254f2 100644
--- a/src/core/convert/SignsInstance.js
+++ b/src/core/convert/SignsInstance.js
@@ -1,5 +1,8 @@
 import _count from './_count.js';
 
+/**
+ * Allows to produce an assignment format that makes sense in sign format.
+ */
 export default class SignsInstance {
 	/**
 	 * Clauses are in parity format.