diff --git a/web3.js/src/connection.js b/web3.js/src/connection.js
index b2090398d2..53fdd9bb5c 100644
--- a/web3.js/src/connection.js
+++ b/web3.js/src/connection.js
@@ -135,6 +135,11 @@ const SendTokensRpcResult = struct({
 
 /**
  * Information describing an account
+ *
+ * @typedef {Object} AccountInfo
+ * @property {number} tokens Number of tokens assigned to the account
+ * @property {PublicKey} programId Identifier of the program assigned to the account
+ * @property {?Buffer} userdata Optional userdata assigned to the account
  */
 type AccountInfo = {
   tokens: number,
diff --git a/web3.js/src/transaction.js b/web3.js/src/transaction.js
index aa9faff12e..23fc39080b 100644
--- a/web3.js/src/transaction.js
+++ b/web3.js/src/transaction.js
@@ -18,6 +18,13 @@ export type TransactionId = string;
 
 /**
  * List of Transaction object fields that may be initialized at construction
+ *
+ * @typedef {Object} TransactionCtorFields
+ * @property {?Buffer} signature
+ * @property {?Array<PublicKey>} keys
+ * @property {?PublicKey} programId
+ * @property {?number} fee
+ * @property {?Buffer} userdata
  */
 type TransactionCtorFields = {|
   signature?: Buffer;