diff --git a/src/plugins/dive/Dive.mli b/src/plugins/dive/Dive.mli
index cce51dc83ef23f10bb7ed95d5a93dfc632b91896..fa8a4b16cfba48dc466ea01e1e5bdc509905eef0 100644
--- a/src/plugins/dive/Dive.mli
+++ b/src/plugins/dive/Dive.mli
@@ -19,3 +19,5 @@
 (*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
 (*                                                                        *)
 (**************************************************************************)
+
+(* This plugin does not export anything to the OCaml API. *)
diff --git a/src/plugins/dive/server_interface.mli b/src/plugins/dive/server_interface.mli
index cce51dc83ef23f10bb7ed95d5a93dfc632b91896..c639db5ea04e8bc2afa6635d04be81d660dccf1c 100644
--- a/src/plugins/dive/server_interface.mli
+++ b/src/plugins/dive/server_interface.mli
@@ -19,3 +19,5 @@
 (*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
 (*                                                                        *)
 (**************************************************************************)
+
+(* Dive API for the server. Nothing is exported. *)
diff --git a/src/plugins/studia/studia_request.mli b/src/plugins/studia/studia_request.mli
index cce51dc83ef23f10bb7ed95d5a93dfc632b91896..6f3514109ea9004e8eea683e5b2e6f92848b19cf 100644
--- a/src/plugins/studia/studia_request.mli
+++ b/src/plugins/studia/studia_request.mli
@@ -19,3 +19,5 @@
 (*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
 (*                                                                        *)
 (**************************************************************************)
+
+(* Studia API for Frama-C server. Nothing is exported. *)
diff --git a/src/plugins/value/api/values_request.mli b/src/plugins/value/api/values_request.mli
index cce51dc83ef23f10bb7ed95d5a93dfc632b91896..006a29467118c7c3ad37a163911f9c815ab61b29 100644
--- a/src/plugins/value/api/values_request.mli
+++ b/src/plugins/value/api/values_request.mli
@@ -19,3 +19,5 @@
 (*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
 (*                                                                        *)
 (**************************************************************************)
+
+(* Eva API to Frama-C server. Nothing is exported. *)