Index: src/wp-includes/option.php
===================================================================
--- src/wp-includes/option.php	(revision 28733)
+++ src/wp-includes/option.php	(working copy)
@@ -620,9 +620,11 @@
  *
  * @since 2.8.0
  *
- * @param string $transient Transient name. Expected to not be SQL-escaped.
- * @param mixed $value Transient value. Must be serializable if non-scalar. Expected to not be SQL-escaped.
- * @param int $expiration Time until expiration in seconds, default 0
+ * @param string $transient  Transient name. Expected to not be SQL-escaped. Must be
+ *                           45 characters or fewer in length.
+ * @param mixed  $value      Transient value. Must be serializable if non-scalar.
+ *                           Expected to not be SQL-escaped.
+ * @param int    $expiration Optional. Time until expiration in seconds. Default 0.
  * @return bool False if value was not set and true if value was set.
  */
 function set_transient( $transient, $value, $expiration = 0 ) {
@@ -1360,9 +1362,10 @@
  *
  * @see set_transient()
  *
- * @param string $transient Transient name. Expected to not be SQL-escaped.
- * @param mixed $value Transient value. Expected to not be SQL-escaped.
- * @param int $expiration Time until expiration in seconds, default 0
+ * @param string $transient  Transient name. Expected to not be SQL-escaped. Must be
+ *                           40 characters or fewer in length.
+ * @param mixed  $value      Transient value. Expected to not be SQL-escaped.
+ * @param int    $expiration Optional. Time until expiration in seconds. Default 0.
  * @return bool False if value was not set and true if value was set.
  */
 function set_site_transient( $transient, $value, $expiration = 0 ) {