In that case, annotating the actual type will help bindings use the correct type.

Compared the gir before and after:
--- Purple-3.0.gir  2025-02-14 00:51:54.467548255 -0500
+++ build/libpurple/Purple-3.0.gir  2025-02-14 02:45:56.050535272 -0500
@@ -19676,8 +19676,9 @@
         <return-value transfer-ownership="full">
           <doc xml:space="preserve"
                filename="libpurple/purplenoopcredentialprovider.h"
-               line="62">The new #PurpleNoopCredentialProvider instance.</doc>
-          <type name="CredentialProvider" c:type="PurpleCredentialProvider*"/>
+               line="62">The new credential provider.</doc>
+          <type name="NoopCredentialProvider"
+                c:type="PurpleCredentialProvider*"/>
         </return-value>
       </constructor>
     </class>
@@ -20412,7 +20413,7 @@
           <doc xml:space="preserve"
                filename="libpurple/purplenotificationaddcontact.h"
                line="65">The new notification.</doc>
-          <type name="Notification" c:type="PurpleNotification*"/>
+          <type name="NotificationAddContact" c:type="PurpleNotification*"/>
         </return-value>
         <parameters>
           <parameter name="id"
@@ -20507,7 +20508,8 @@
           <doc xml:space="preserve"
                filename="libpurple/purplenotificationauthorizationrequest.h"
                line="65">The new notification.</doc>
-          <type name="Notification" c:type="PurpleNotification*"/>
+          <type name="NotificationAuthorizationRequest"
+                c:type="PurpleNotification*"/>
         </return-value>
         <parameters>
           <parameter name="id"
@@ -20608,11 +20610,12 @@
              line="55">Creates a new [class@Notification] for a connection error on @account.</doc>
         <source-position filename="libpurple/purplenotificationconnectionerror.h"
                          line="67"/>
-        <return-value transfer-ownership="full" nullable="1">
+        <return-value transfer-ownership="full">
           <doc xml:space="preserve"
                filename="libpurple/purplenotificationconnectionerror.h"
                line="62">The new notification.</doc>
-          <type name="Notification" c:type="PurpleNotification*"/>
+          <type name="NotificationConnectionError"
+                c:type="PurpleNotification*"/>
         </return-value>
         <parameters>
           <parameter name="id"
@@ -20668,7 +20671,7 @@
           <doc xml:space="preserve"
                filename="libpurple/purplenotificationlink.h"
                line="61">The new notification.</doc>
-          <type name="Notification" c:type="PurpleNotification*"/>
+          <type name="NotificationLink" c:type="PurpleNotification*"/>
         </return-value>
         <parameters>
           <parameter name="id"
@@ -21881,8 +21884,8 @@
         <return-value transfer-ownership="full">
           <doc xml:space="preserve"
                filename="libpurple/purpleplugininfo.h"
-               line="207">A new #PurplePluginInfo instance.</doc>
-          <type name="GPlugin.PluginInfo" c:type="GPluginPluginInfo*"/>
+               line="207">The new plugin info.</doc>
+          <type name="PluginInfo" c:type="GPluginPluginInfo*"/>
         </return-value>
         <parameters>
           <parameter name="first_property" transfer-ownership="none">
@@ -31364,7 +31367,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldaccount.h"
                line="79">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldAccount" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -31737,7 +31740,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldbool.h"
                line="61">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldBool" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -31918,7 +31921,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldchoice.h"
                line="61">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldChoice" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -32281,7 +32284,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldimage.h"
                line="63">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldImage" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -32508,7 +32511,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldint.h"
                line="61">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldInt" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -32825,7 +32828,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldlabel.h"
                line="58">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldLabel" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -32876,7 +32879,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldlist.h"
                line="58">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldList" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -33230,7 +33233,7 @@
           <doc xml:space="preserve"
                filename="libpurple/request/purplerequestfieldstring.h"
                line="60">The new field.</doc>
-          <type name="RequestField" c:type="PurpleRequestField*"/>
+          <type name="RequestFieldString" c:type="PurpleRequestField*"/>
         </return-value>
         <parameters>
           <parameter name="id" transfer-ownership="none">
@@ -35252,8 +35255,8 @@
         <return-value transfer-ownership="full">
           <doc xml:space="preserve"
                filename="libpurple/purplesqlitehistoryadapter.h"
-               line="60">The new #PurpleSqliteHistoryAdapter instance.</doc>
-          <type name="HistoryAdapter" c:type="PurpleHistoryAdapter*"/>
+               line="60">The new history adapter.</doc>
+          <type name="SqliteHistoryAdapter" c:type="PurpleHistoryAdapter*"/>
         </return-value>
         <parameters>
           <parameter name="filename" transfer-ownership="none">