doxy: group 6 new apis

- Account Private Data
- Connection Account
- Email Private Data
- IMAP Authenticaion
- Mailbox Private Data
- POP Authenticaion

and fill-in a few other gaps.

103 files changed, 258 insertions, 230 deletions

diff --git a/alias/dlg_alias.c b/alias/dlg_alias.c
index f49640ebe..efaf43fb2 100644
--- a/alias/dlg_alias.c
+++ b/alias/dlg_alias.c
@@ -163,7 +163,7 @@ static const char *alias_format_str(char *buf, size_t buflen, size_t col, int co
 }
 
 /**
- * alias_make_entry - Format a menu item for the alias list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * alias_make_entry - Format an Alias for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $alias_format, alias_format_str()
  */
diff --git a/alias/dlg_query.c b/alias/dlg_query.c
index 9c235dfb2..0e0832ece 100644
--- a/alias/dlg_query.c
+++ b/alias/dlg_query.c
@@ -217,7 +217,7 @@ static const char *query_format_str(char *buf, size_t buflen, size_t col, int co
 }
 
 /**
- * query_make_entry - Format a menu item for the query list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * query_make_entry - Format an Alias for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $query_format, query_format_str()
  */
diff --git a/attach/dlg_attach.c b/attach/dlg_attach.c
index 0f9976e4b..f8f7febd8 100644
--- a/attach/dlg_attach.c
+++ b/attach/dlg_attach.c
@@ -396,7 +396,7 @@ const char *attach_format_str(char *buf, size_t buflen, size_t col, int cols, ch
 }
 
 /**
- * attach_make_entry - Format a menu item for the attachment list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * attach_make_entry - Format an Attachment for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $attach_format, attach_format_str()
  */
diff --git a/attach/private_data.c b/attach/private_data.c
index 8808c8f79..1782bb4b8 100644
--- a/attach/private_data.c
+++ b/attach/private_data.c
@@ -31,7 +31,7 @@
 #include "private_data.h"
 
 /**
- * attach_private_data_free - Free Attach Data - Implements Menu::mdata_free() - @ingroup menu_mdata_free
+ * attach_private_data_free - Free the Attach Data - Implements Menu::mdata_free() - @ingroup menu_mdata_free
  * @param menu Menu
  * @param ptr  Attach Data to free
  */
diff --git a/autocrypt/dlg_autocrypt.c b/autocrypt/dlg_autocrypt.c
index e27939e64..20919a07c 100644
--- a/autocrypt/dlg_autocrypt.c
+++ b/autocrypt/dlg_autocrypt.c
@@ -175,7 +175,7 @@ static const char *autocrypt_format_str(char *buf, size_t buflen, size_t col, in
 }
 
 /**
- * autocrypt_make_entry - Create a line for the Autocrypt account menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * autocrypt_make_entry - Format an Autocrypt Account for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $autocrypt_acct_format, autocrypt_format_str()
  */
diff --git a/browser/dlg_browser.c b/browser/dlg_browser.c
index f959f2524..0f96bba2f 100644
--- a/browser/dlg_browser.c
+++ b/browser/dlg_browser.c
@@ -904,7 +904,9 @@ static int select_file_search(struct Menu *menu, regex_t *rx, int line)
 }
 
 /**
- * folder_make_entry - Format a menu item for the folder browser - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * folder_make_entry - Format a Folder for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ *
+ * @sa $folder_format, $group_index_format, $mailbox_folder_format, folder_format_str()
  */
 static void folder_make_entry(struct Menu *menu, char *buf, size_t buflen, int line)
 {
diff --git a/color/command.c b/color/command.c
index 1d9b3fe20..e7e36c9d4 100644
--- a/color/command.c
+++ b/color/command.c
@@ -864,7 +864,7 @@ static enum CommandResult parse_uncolor(struct Buffer *buf, struct Buffer *s,
 
 #ifdef USE_DEBUG_COLOR
 /**
- * color_dump - Parse 'color' command to display colours - Implements ICommand::parse()
+ * color_dump - Parse 'color' command to display colours - Implements Command::parse() - @ingroup command_parse
  */
 static enum CommandResult color_dump(struct Buffer *buf, struct Buffer *s,
                                      intptr_t data, struct Buffer *err)
diff --git a/compose/attach.c b/compose/attach.c
index 64e88571d..e0b6cff3a 100644
--- a/compose/attach.c
+++ b/compose/attach.c
@@ -211,7 +211,7 @@ static int compose_attach_tag(struct Menu *menu, int sel, int act)
 }
 
 /**
- * compose_make_entry - Format a menu item for the attachment list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * compose_make_entry - Format an Attachment for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $attach_format, attach_format_str()
  */
diff --git a/compose/cbar_data.c b/compose/cbar_data.c
index b3736a917..7653cfa61 100644
--- a/compose/cbar_data.c
+++ b/compose/cbar_data.c
@@ -31,7 +31,7 @@
 #include "cbar_data.h"
 
 /**
- * cbar_data_free - Free the private Compose Bar data attached to the MuttWindow - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * cbar_data_free - Free the private Compose Bar data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 void cbar_data_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/compose/shared_data.c b/compose/shared_data.c
index 491bf8738..2e265e59e 100644
--- a/compose/shared_data.c
+++ b/compose/shared_data.c
@@ -31,7 +31,7 @@
 #include "shared_data.h"
 
 /**
- * compose_shared_data_free - Create the compose shared data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * compose_shared_data_free - Free the compose shared data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 void compose_shared_data_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/compress/lz4.c b/compress/lz4.c
index b20deef91..79d9ceda5 100644
--- a/compress/lz4.c
+++ b/compress/lz4.c
@@ -72,7 +72,7 @@ static struct Lz4ComprData *lz4_cdata_new(void)
 }
 
 /**
- * compr_lz4_open - Implements ComprOps::open() - @ingroup compress_open
+ * compr_lz4_open - Open a compression context - Implements ComprOps::open() - @ingroup compress_open
  */
 static ComprHandle *compr_lz4_open(short level)
 {
@@ -94,7 +94,7 @@ static ComprHandle *compr_lz4_open(short level)
 }
 
 /**
- * compr_lz4_compress - Implements ComprOps::compress() - @ingroup compress_compress
+ * compr_lz4_compress - Compress header cache data - Implements ComprOps::compress() - @ingroup compress_compress
  */
 static void *compr_lz4_compress(ComprHandle *handle, const char *data,
                                 size_t dlen, size_t *clen)
@@ -131,7 +131,7 @@ static void *compr_lz4_compress(ComprHandle *handle, const char *data,
 }
 
 /**
- * compr_lz4_decompress - Implements ComprOps::decompress() - @ingroup compress_decompress
+ * compr_lz4_decompress - Decompress header cache data - Implements ComprOps::decompress() - @ingroup compress_decompress
  */
 static void *compr_lz4_decompress(ComprHandle *handle, const char *cbuf, size_t clen)
 {
@@ -162,7 +162,7 @@ static void *compr_lz4_decompress(ComprHandle *handle, const char *cbuf, size_t
 }
 
 /**
- * compr_lz4_close - Implements ComprOps::close() - @ingroup compress_close
+ * compr_lz4_close - Close a compression context - Implements ComprOps::close() - @ingroup compress_close
  */
 static void compr_lz4_close(ComprHandle **ptr)
 {
diff --git a/compress/zlib.c b/compress/zlib.c
index 57cd5a813..37a0bedc4 100644
--- a/compress/zlib.c
+++ b/compress/zlib.c
@@ -72,7 +72,7 @@ static struct ZlibComprData *zlib_cdata_new(void)
 }
 
 /**
- * compr_zlib_open - Implements ComprOps::open() - @ingroup compress_open
+ * compr_zlib_open - Open a compression context - Implements ComprOps::open() - @ingroup compress_open
  */
 static ComprHandle *compr_zlib_open(short level)
 {
@@ -94,7 +94,7 @@ static ComprHandle *compr_zlib_open(short level)
 }
 
 /**
- * compr_zlib_compress - Implements ComprOps::compress() - @ingroup compress_compress
+ * compr_zlib_compress - Compress header cache data - Implements ComprOps::compress() - @ingroup compress_compress
  */
 static void *compr_zlib_compress(ComprHandle *handle, const char *data,
                                  size_t dlen, size_t *clen)
@@ -128,7 +128,7 @@ static void *compr_zlib_compress(ComprHandle *handle, const char *data,
 }
 
 /**
- * compr_zlib_decompress - Implements ComprOps::decompress() - @ingroup compress_decompress
+ * compr_zlib_decompress - Decompress header cache data - Implements ComprOps::decompress() - @ingroup compress_decompress
  */
 static void *compr_zlib_decompress(ComprHandle *handle, const char *cbuf, size_t clen)
 {
@@ -157,7 +157,7 @@ static void *compr_zlib_decompress(ComprHandle *handle, const char *cbuf, size_t
 }
 
 /**
- * compr_zlib_close - Implements ComprOps::close() - @ingroup compress_close
+ * compr_zlib_close - Close a compression context - Implements ComprOps::close() - @ingroup compress_close
  */
 static void compr_zlib_close(ComprHandle **ptr)
 {
diff --git a/compress/zstd.c b/compress/zstd.c
index c2508a2f1..bd1f14fcd 100644
--- a/compress/zstd.c
+++ b/compress/zstd.c
@@ -74,7 +74,7 @@ static struct ZstdComprData *zstd_cdata_new(void)
 }
 
 /**
- * compr_zstd_open - Implements ComprOps::open() - @ingroup compress_open
+ * compr_zstd_open - Open a compression context - Implements ComprOps::open() - @ingroup compress_open
  */
 static ComprHandle *compr_zstd_open(short level)
 {
@@ -108,7 +108,7 @@ static ComprHandle *compr_zstd_open(short level)
 }
 
 /**
- * compr_zstd_compress - Implements ComprOps::compress() - @ingroup compress_compress
+ * compr_zstd_compress - Compress header cache data - Implements ComprOps::compress() - @ingroup compress_compress
  */
 static void *compr_zstd_compress(ComprHandle *handle, const char *data,
                                  size_t dlen, size_t *clen)
@@ -132,7 +132,7 @@ static void *compr_zstd_compress(ComprHandle *handle, const char *data,
 }
 
 /**
- * compr_zstd_decompress - Implements ComprOps::decompress() - @ingroup compress_decompress
+ * compr_zstd_decompress - Decompress header cache data - Implements ComprOps::decompress() - @ingroup compress_decompress
  */
 static void *compr_zstd_decompress(ComprHandle *handle, const char *cbuf, size_t clen)
 {
@@ -159,7 +159,7 @@ static void *compr_zstd_decompress(ComprHandle *handle, const char *cbuf, size_t
 }
 
 /**
- * compr_zstd_close - Implements ComprOps::close() - @ingroup compress_close
+ * compr_zstd_close - Close a compression context - Implements ComprOps::close() - @ingroup compress_close
  */
 static void compr_zstd_close(ComprHandle **ptr)
 {
diff --git a/config/charset.c b/config/charset.c
index d0569a2de..cb141d875 100644
--- a/config/charset.c
+++ b/config/charset.c
@@ -35,7 +35,9 @@
 #include "set.h"
 
 /**
- * charset_validator - Validate the "charset" config variable - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ * charset_validator - Validate the "charset" config variables - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ *
+ * Validate the config variables that contain a single charset.
  */
 int charset_validator(const struct ConfigSet *cs, const struct ConfigDef *cdef,
                       intptr_t value, struct Buffer *err)
@@ -73,8 +75,9 @@ int charset_validator(const struct ConfigSet *cs, const struct ConfigDef *cdef,
 }
 
 /**
- * charset_slist_validator - Validate the "charset" config variable - Implements ConfigDef::validator() - @ingroup cfg_def_validator
- * This is a version for charset options is Slist.
+ * charset_slist_validator - Validate the multiple "charset" config variables - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ *
+ * Validate the config variables that can contain a multiple charsets.
  */
 int charset_slist_validator(const struct ConfigSet *cs, const struct ConfigDef *cdef,
                             intptr_t value, struct Buffer *err)
diff --git a/config/myvar.c b/config/myvar.c
index 3dad89e6a..014a9f06b 100644
--- a/config/myvar.c
+++ b/config/myvar.c
@@ -144,7 +144,7 @@ static intptr_t myvar_native_get(const struct ConfigSet *cs, void *var,
 }
 
 /**
- * myvar_string_plus_equals - Concat string to a MyVar - Implements ConfigSetType::string_plus_equals() - @ingroup cfg_type_string_plus_equals
+ * myvar_string_plus_equals - Add to a MyVar by string - Implements ConfigSetType::string_plus_equals() - @ingroup cfg_type_string_plus_equals
  */
 static int myvar_string_plus_equals(const struct ConfigSet *cs, void *var,
                                     const struct ConfigDef *cdef,
diff --git a/config/set.c b/config/set.c
index db21881ce..b5afad99b 100644
--- a/config/set.c
+++ b/config/set.c
@@ -35,7 +35,7 @@
 #include "types.h"
 
 /**
- * cs_hashelem_free - Callback function for the Hash Table - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
+ * cs_hashelem_free - Free our hash table data - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
  * @param type Object type, e.g. #DT_STRING
  * @param obj  Object to destroy
  * @param data ConfigSet associated with the object
diff --git a/config/slist.c b/config/slist.c
index b7f93f29f..c7caf3ca8 100644
--- a/config/slist.c
+++ b/config/slist.c
@@ -223,7 +223,7 @@ static int slist_string_plus_equals(const struct ConfigSet *cs, void *var,
 }
 
 /**
- * slist_string_minus_equals - Remove from a Slist by string - Implements ConfigSetType::string_plus_equals() - @ingroup cfg_type_string_plus_equals
+ * slist_string_minus_equals - Remove from a Slist by string - Implements ConfigSetType::string_minus_equals() - @ingroup cfg_type_string_minus_equals
  */
 static int slist_string_minus_equals(const struct ConfigSet *cs, void *var,
                                      const struct ConfigDef *cdef,
diff --git a/config/string.c b/config/string.c
index 7f6885946..79019fa33 100644
--- a/config/string.c
+++ b/config/string.c
@@ -177,7 +177,7 @@ static intptr_t string_native_get(const struct ConfigSet *cs, void *var,
 }
 
 /**
- * string_string_plus_equals - Concat String to a string - Implements ConfigSetType::string_plus_equals() - @ingroup cfg_type_string_plus_equals
+ * string_string_plus_equals - Add to a String by string - Implements ConfigSetType::string_plus_equals() - @ingroup cfg_type_string_plus_equals
  */
 static int string_string_plus_equals(const struct ConfigSet *cs, void *var,
                                      const struct ConfigDef *cdef,
diff --git a/conn/connaccount.h b/conn/connaccount.h
index db1df6f2b..fff32e13a 100644
--- a/conn/connaccount.h
+++ b/conn/connaccount.h
@@ -61,6 +61,8 @@ struct ConnAccount
   const char *service;    ///< Name of the service, e.g. "imap"
 
   /**
+   * @defgroup conn_account_get_field Connection Account API
+   *
    * get_field - Function to get some login credentials
    * @param field Field to get, e.g. #MUTT_CA_PASS
    * @retval ptr Requested string
diff --git a/conn/dlg_verifycert.c b/conn/dlg_verifycert.c
index 6b2c76677..7a955ec22 100644
--- a/conn/dlg_verifycert.c
+++ b/conn/dlg_verifycert.c
@@ -127,7 +127,7 @@ static int menu_dialog_translate_op(int op)
 }
 
 /**
- * cert_make_entry - Create a string to display in a Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * cert_make_entry - Create a Certificate for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  */
 static void cert_make_entry(struct Menu *menu, char *buf, size_t buflen, int line)
 {
diff --git a/conn/gnutls.c b/conn/gnutls.c
index a90d9a6d7..4d4a80892 100644
--- a/conn/gnutls.c
+++ b/conn/gnutls.c
@@ -982,7 +982,7 @@ fail:
 }
 
 /**
- * tls_socket_poll - Check whether a socket read would block - Implements Connection::poll() - @ingroup connection_poll
+ * tls_socket_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 static int tls_socket_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/conn/openssl.c b/conn/openssl.c
index 5aee948c8..79136b13d 100644
--- a/conn/openssl.c
+++ b/conn/openssl.c
@@ -1298,7 +1298,7 @@ free_ssldata:
 }
 
 /**
- * ssl_socket_poll - Check whether a socket read would block - Implements Connection::poll() - @ingroup connection_poll
+ * ssl_socket_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 static int ssl_socket_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/conn/raw.c b/conn/raw.c
index 15047f11d..f3eb4fdec 100644
--- a/conn/raw.c
+++ b/conn/raw.c
@@ -336,7 +336,7 @@ int raw_socket_write(struct Connection *conn, const char *buf, size_t count)
 }
 
 /**
- * raw_socket_poll - Checks whether reads would block - Implements Connection::poll() - @ingroup connection_poll
+ * raw_socket_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 int raw_socket_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/conn/sasl.c b/conn/sasl.c
index 52d595074..4c2a00654 100644
--- a/conn/sasl.c
+++ b/conn/sasl.c
@@ -89,7 +89,7 @@ struct SaslSockData
   int (*write)(struct Connection *conn, const char *buf, size_t count);
 
   /**
-   * poll - Check whether a socket read would block - Implements Connection::poll() - @ingroup connection_poll
+   * poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
    */
   int (*poll)(struct Connection *conn, time_t wait_secs);
 
@@ -578,7 +578,7 @@ fail:
 }
 
 /**
- * mutt_sasl_conn_poll - Check an SASL connection for data - Implements Connection::poll() - @ingroup connection_poll
+ * mutt_sasl_conn_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 static int mutt_sasl_conn_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/conn/tunnel.c b/conn/tunnel.c
index 743fdcb60..041560bc6 100644
--- a/conn/tunnel.c
+++ b/conn/tunnel.c
@@ -190,7 +190,7 @@ static int tunnel_socket_write(struct Connection *conn, const char *buf, size_t
 }
 
 /**
- * tunnel_socket_poll - Checks whether tunnel reads would block - Implements Connection::poll() - @ingroup connection_poll
+ * tunnel_socket_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 static int tunnel_socket_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/conn/zstrm.c b/conn/zstrm.c
index bc93ffa32..c754222ab 100644
--- a/conn/zstrm.c
+++ b/conn/zstrm.c
@@ -206,7 +206,7 @@ retry:
 }
 
 /**
- * zstrm_poll - Checks whether reads would block - Implements Connection::poll() - @ingroup connection_poll
+ * zstrm_poll - Check if any data is waiting on a socket - Implements Connection::poll() - @ingroup connection_poll
  */
 static int zstrm_poll(struct Connection *conn, time_t wait_secs)
 {
diff --git a/core/account.h b/core/account.h
index 25f49df41..dcebd282c 100644
--- a/core/account.h
+++ b/core/account.h
@@ -43,6 +43,8 @@ struct Account
   void *adata;                    ///< Private data (for Mailbox backends)
 
   /**
+   * @defgroup account_adata_free Account Private Data API
+   *
    * adata_free - Free the private data attached to the Account
    * @param ptr Private data to be freed
    *
diff --git a/core/mailbox.h b/core/mailbox.h
index c4329ed66..c36a43622 100644
--- a/core/mailbox.h
+++ b/core/mailbox.h
@@ -133,6 +133,8 @@ struct Mailbox
   void *mdata;                        ///< Driver specific data
 
   /**
+   * @defgroup mailbox_mdata_free Mailbox Private Data API
+   *
    * mdata_free - Free the private data attached to the Mailbox
    * @param ptr Private data to be freed
    *
diff --git a/email/email.h b/email/email.h
index 536092178..e903e46b2 100644
--- a/email/email.h
+++ b/email/email.h
@@ -77,6 +77,8 @@ struct Email
   bool purge           : 1;    ///< Skip trash folder when deleting
 
   /**
+   * @defgroup email_edata_free Email Private Data API
+   *
    * edata_free - Free the private data attached to the Email
    * @param ptr Private data to be freed
    *
diff --git a/email/tags.c b/email/tags.c
index da340499e..81b36802e 100644
--- a/email/tags.c
+++ b/email/tags.c
@@ -205,7 +205,7 @@ bool driver_tags_replace(struct TagList *head, const char *tags)
 }
 
 /**
- * tags_deleter - Delete a tag - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
+ * tags_deleter - Free our hash table data - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
  */
 static void tags_deleter(int type, void *obj, intptr_t data)
 {
diff --git a/gui/msgwin_wdata.c b/gui/msgwin_wdata.c
index 127c3f327..5bf688f81 100644
--- a/gui/msgwin_wdata.c
+++ b/gui/msgwin_wdata.c
@@ -32,7 +32,7 @@
 #include "msgwin_wdata.h"
 
 /**
- * msgwin_wdata_free - Free the private data attached to the Message Window - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * msgwin_wdata_free - Free the private data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 void msgwin_wdata_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/gui/sbar.c b/gui/sbar.c
index 4dd499853..7cdd04494 100644
--- a/gui/sbar.c
+++ b/gui/sbar.c
@@ -173,7 +173,7 @@ static int sbar_window_observer(struct NotifyCallback *nc)
 }
 
 /**
- * sbar_wdata_free - Free the private data of the Simple Bar attached to the MuttWindow - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * sbar_wdata_free - Free the private data of the Simple Bar - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 static void sbar_wdata_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/history/dlg_history.c b/history/dlg_history.c
index 046235ccc..c1b58dbf5 100644
--- a/history/dlg_history.c
+++ b/history/dlg_history.c
@@ -104,7 +104,7 @@ static const char *history_format_str(char *buf, size_t buflen, size_t col, int
 }
 
 /**
- * history_make_entry - Format a menu item for the history list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * history_make_entry - Format a History Item for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa history_format_str()
  */
diff --git a/history/history.c b/history/history.c
index d414d13ed..c5dc6240b 100644
--- a/history/history.c
+++ b/history/history.c
@@ -694,8 +694,7 @@ void mutt_hist_complete(char *buf, size_t buflen, enum HistoryClass hclass)
 }
 
 /**
- * main_hist_observer - Notification that a Config Variable has change
- - Implements ::observer_t - @ingroup observer_api
+ * main_hist_observer - Notification that a Config Variable has change - Implements ::observer_t - @ingroup observer_api
  */
 int main_hist_observer(struct NotifyCallback *nc)
 {
diff --git a/hook.c b/hook.c
index 05639b4d8..789a205c5 100644
--- a/hook.c
+++ b/hook.c
@@ -379,7 +379,7 @@ void mutt_delete_hooks(HookFlags type)
 }
 
 /**
- * idxfmt_hashelem_free - Delete an index-format-hook from the Hash Table - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
+ * idxfmt_hashelem_free - Free our hash table data - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
  */
 static void idxfmt_hashelem_free(int type, void *obj, intptr_t data)
 {
diff --git a/imap/adata.c b/imap/adata.c
index 2a0b5bdd6..7c7745c13 100644
--- a/imap/adata.c
+++ b/imap/adata.c
@@ -64,7 +64,7 @@ static int imap_timeout_observer(struct NotifyCallback *nc)
 }
 
 /**
- * imap_adata_free - Free the private Account data - Implements Account::adata_free()
+ * imap_adata_free - Free the private Account data - Implements Account::adata_free() - @ingroup account_adata_free
  */
 void imap_adata_free(void **ptr)
 {
diff --git a/imap/auth.c b/imap/auth.c
index f4ff5f216..108e68406 100644
--- a/imap/auth.c
+++ b/imap/auth.c
@@ -42,6 +42,8 @@
 struct ImapAuth
 {
   /**
+   * @defgroup imap_authenticate IMAP Authenticaion API
+   *
    * authenticate - Authenticate an IMAP connection
    * @param adata Imap Account data
    * @param method Use this named method, or any available method if NULL
diff --git a/imap/auth_anon.c b/imap/auth_anon.c
index 6a75526d1..767c1cb8d 100644
--- a/imap/auth_anon.c
+++ b/imap/auth_anon.c
@@ -34,7 +34,7 @@
 #include "auth.h"
 
 /**
- * imap_auth_anon - Authenticate anonymously - Implements ImapAuth::authenticate()
+ * imap_auth_anon - Authenticate anonymously - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  *
  * This is basically a stripped-down version of the cram-md5 method.
  */
diff --git a/imap/auth_cram.c b/imap/auth_cram.c
index 2e16fb261..85364b58b 100644
--- a/imap/auth_cram.c
+++ b/imap/auth_cram.c
@@ -90,7 +90,7 @@ static void hmac_md5(const char *password, char *challenge, unsigned char *respo
 }
 
 /**
- * imap_auth_cram_md5 - Authenticate using CRAM-MD5 - Implements ImapAuth::authenticate()
+ * imap_auth_cram_md5 - Authenticate using CRAM-MD5 - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_cram_md5(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_gsasl.c b/imap/auth_gsasl.c
index d976c9284..a24eb2d4f 100644
--- a/imap/auth_gsasl.c
+++ b/imap/auth_gsasl.c
@@ -36,7 +36,7 @@
 #include "auth.h"
 
 /**
- * imap_auth_gsasl - GNU SASL authenticator - Implements ImapAuth::authenticate()
+ * imap_auth_gsasl - GNU SASL authenticator - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_gsasl(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_gss.c b/imap/auth_gss.c
index 66f8c9e5c..97ebdc7da 100644
--- a/imap/auth_gss.c
+++ b/imap/auth_gss.c
@@ -99,7 +99,7 @@ static void print_gss_error(OM_uint32 err_maj, OM_uint32 err_min)
 }
 
 /**
- * imap_auth_gss - GSS Authentication support - Implements ImapAuth::authenticate()
+ * imap_auth_gss - GSS Authentication support - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_gss(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_login.c b/imap/auth_login.c
index 7ab027c7d..87436d5f6 100644
--- a/imap/auth_login.c
+++ b/imap/auth_login.c
@@ -39,7 +39,7 @@
 #include "mutt_logging.h"
 
 /**
- * imap_auth_login - Plain LOGIN support - Implements ImapAuth::authenticate()
+ * imap_auth_login - Plain LOGIN support - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_login(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_oauth.c b/imap/auth_oauth.c
index f9544040c..0728f4d03 100644
--- a/imap/auth_oauth.c
+++ b/imap/auth_oauth.c
@@ -104,7 +104,7 @@ static enum ImapAuthRes imap_auth_oauth_xoauth2(struct ImapAccountData *adata,
 }
 
 /**
- * imap_auth_oauth - Authenticate an IMAP connection using OAUTHBEARER - Implements ImapAuth::authenticate()
+ * imap_auth_oauth - Authenticate an IMAP connection using OAUTHBEARER - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_oauth(struct ImapAccountData *adata, const char *method)
 {
@@ -112,7 +112,7 @@ enum ImapAuthRes imap_auth_oauth(struct ImapAccountData *adata, const char *meth
 }
 
 /**
- * imap_auth_xoauth2 - Authenticate an IMAP connection using XOAUTH2 - Implements ImapAuth::authenticate()
+ * imap_auth_xoauth2 - Authenticate an IMAP connection using XOAUTH2 - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_xoauth2(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_plain.c b/imap/auth_plain.c
index 1bf9faef7..032871444 100644
--- a/imap/auth_plain.c
+++ b/imap/auth_plain.c
@@ -36,7 +36,7 @@
 #include "mutt_logging.h"
 
 /**
- * imap_auth_plain - SASL PLAIN support - Implements ImapAuth::authenticate()
+ * imap_auth_plain - SASL PLAIN support - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_plain(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/auth_sasl.c b/imap/auth_sasl.c
index d9e4600af..6918462f1 100644
--- a/imap/auth_sasl.c
+++ b/imap/auth_sasl.c
@@ -40,7 +40,7 @@
 #include "auth.h"
 
 /**
- * imap_auth_sasl - SASL authenticator - Implements ImapAuth::authenticate()
+ * imap_auth_sasl - SASL authenticator - Implements ImapAuth::authenticate() - @ingroup imap_authenticate
  */
 enum ImapAuthRes imap_auth_sasl(struct ImapAccountData *adata, const char *method)
 {
diff --git a/imap/edata.c b/imap/edata.c
index 316ec1d9b..569f7b69e 100644
--- a/imap/edata.c
+++ b/imap/edata.c
@@ -34,7 +34,7 @@
 #include "edata.h"
 
 /**
- * imap_edata_free - Free the private Email data - Implements Email::edata_free()
+ * imap_edata_free - Free the private Email data - Implements Email::edata_free() - @ingroup email_edata_free
  */
 void imap_edata_free(void **ptr)
 {
diff --git a/imap/mdata.c b/imap/mdata.c
index 65795f0a6..e614e551a 100644
--- a/imap/mdata.c
+++ b/imap/mdata.c
@@ -34,7 +34,7 @@
 #include "adata.h"
 
 /**
- * imap_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free()
+ * imap_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free() - @ingroup mailbox_mdata_free
  */
 void imap_mdata_free(void **ptr)
 {
diff --git a/imap/message.c b/imap/message.c
index bab5afa3d..f409bba41 100644
--- a/imap/message.c
+++ b/imap/message.c
@@ -160,10 +160,10 @@ static int msg_cache_commit(struct Mailbox *m, struct Email *e)
 }
 
 /**
- * msg_cache_clean_cb - Delete an entry from the message cache - Implements ::bcache_list_t - @ingroup bcache_list_api
+ * imap_bcache_delete - Delete an entry from the message cache - Implements ::bcache_list_t - @ingroup bcache_list_api
  * @retval 0 Always
  */
-static int msg_cache_clean_cb(const char *id, struct BodyCache *bcache, void *data)
+static int imap_bcache_delete(const char *id, struct BodyCache *bcache, void *data)
 {
   uint32_t uv;
   unsigned int uid;
@@ -1873,7 +1873,7 @@ int imap_cache_clean(struct Mailbox *m)
     return -1;
 
   mdata->bcache = imap_bcache_open(m);
-  mutt_bcache_list(mdata->bcache, msg_cache_clean_cb, mdata);
+  mutt_bcache_list(mdata->bcache, imap_bcache_delete, mdata);
 
   return 0;
 }
diff --git a/imap/util.c b/imap/util.c
index ed45a5c58..97723e8e5 100644
--- a/imap/util.c
+++ b/imap/util.c
@@ -198,7 +198,7 @@ void imap_clean_path(char *path, size_t plen)
 }
 
 /**
- * imap_get_field - Get connection login credentials - Implements ConnAccount::get_field()
+ * imap_get_field - Get connection login credentials - Implements ConnAccount::get_field() - @ingroup conn_account_get_field
  */
 static const char *imap_get_field(enum ConnAccountField field, void *gf_data)
 {
diff --git a/index/dlg_index.c b/index/dlg_index.c
index dcf40e45a..263aea1d1 100644
--- a/index/dlg_index.c
+++ b/index/dlg_index.c
@@ -792,7 +792,9 @@ void change_folder_string(struct Menu *menu, struct Buffer *buf, int *oldcount,
 }
 
 /**
- * index_make_entry - Format a menu item for the index list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * index_make_entry - Format an Email for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ *
+ * @sa $index_format, index_format_str()
  */
 void index_make_entry(struct Menu *menu, char *buf, size_t buflen, int line)
 {
diff --git a/index/ibar.c b/index/ibar.c
index a6e0e6225..fc508898a 100644
--- a/index/ibar.c
+++ b/index/ibar.c
@@ -293,7 +293,7 @@ static int ibar_window_observer(struct NotifyCallback *nc)
 }
 
 /**
- * ibar_data_free - Free the private data attached to the MuttWindow - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * ibar_data_free - Free the private data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 static void ibar_data_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/key/dump.c b/key/dump.c
index 9c3017bb2..641dac8cb 100644
--- a/key/dump.c
+++ b/key/dump.c
@@ -166,7 +166,7 @@ static void dump_all_macros(struct Buffer *buf)
 }
 
 /**
- * dump_bind_macro - Parse 'bind' and 'macro' commands - Implements ICommand::parse()
+ * dump_bind_macro - Parse 'bind' and 'macro' commands - Implements Command::parse() - @ingroup command_parse
  */
 enum CommandResult dump_bind_macro(struct Buffer *buf, struct Buffer *s,
                                    intptr_t data, struct Buffer *err)
diff --git a/maildir/edata.c b/maildir/edata.c
index fd8231a2b..1209f8f6a 100644
--- a/maildir/edata.c
+++ b/maildir/edata.c
@@ -33,7 +33,7 @@
 #include "edata.h"
 
 /**
- * maildir_edata_free - Free the private Email data - Implements Email::edata_free()
+ * maildir_edata_free - Free the private Email data - Implements Email::edata_free() - @ingroup email_edata_free
  */
 void maildir_edata_free(void **ptr)
 {
diff --git a/maildir/maildir.c b/maildir/maildir.c
index ef5bff411..2946e5f79 100644
--- a/maildir/maildir.c
+++ b/maildir/maildir.c
@@ -1102,7 +1102,7 @@ int maildir_check_empty(struct Buffer *path)
 }
 
 /**
- * maildir_ac_owns_path - Check whether an Account own a Mailbox path - Implements MxOps::ac_owns_path() - @ingroup mx_ac_owns_path
+ * maildir_ac_owns_path - Check whether an Account owns a Mailbox path - Implements MxOps::ac_owns_path() - @ingroup mx_ac_owns_path
  */
 static bool maildir_ac_owns_path(struct Account *a, const char *path)
 {
diff --git a/maildir/mdata.c b/maildir/mdata.c
index f1f25df8b..a73540ebd 100644
--- a/maildir/mdata.c
+++ b/maildir/mdata.c
@@ -32,7 +32,7 @@
 #include "mdata.h"
 
 /**
- * maildir_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free()
+ * maildir_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free() - @ingroup mailbox_mdata_free
  */
 void maildir_mdata_free(void **ptr)
 {
diff --git a/maildir/mh.c b/maildir/mh.c
index d71dad42e..e3ebe2710 100644
--- a/maildir/mh.c
+++ b/maildir/mh.c
@@ -814,7 +814,7 @@ static int mh_msg_save_hcache(struct Mailbox *m, struct Email *e)
 }
 
 /**
- * mh_ac_owns_path - Check whether an Account own a Mailbox path - Implements MxOps::ac_owns_path() - @ingroup mx_ac_owns_path
+ * mh_ac_owns_path - Check whether an Account owns a Mailbox path - Implements MxOps::ac_owns_path() - @ingroup mx_ac_owns_path
  */
 static bool mh_ac_owns_path(struct Account *a, const char *path)
 {
diff --git a/mbox/mbox.c b/mbox/mbox.c
index f2635d858..08d0f30a1 100644
--- a/mbox/mbox.c
+++ b/mbox/mbox.c
@@ -73,7 +73,7 @@ struct MUpdate
 };
 
 /**
- * mbox_adata_free - Free the private Account data - Implements Account::adata_free()
+ * mbox_adata_free - Free the private Account data - Implements Account::adata_free() - @ingroup account_adata_free
  */
 static void mbox_adata_free(void **ptr)
 {
diff --git a/menu/window.c b/menu/window.c
index 9ce3cd730..5c742755f 100644
--- a/menu/window.c
+++ b/menu/window.c
@@ -124,7 +124,7 @@ static int menu_repaint(struct MuttWindow *win)
 }
 
 /**
- * menu_wdata_free - Destroy a Menu Window - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * menu_wdata_free - Free the Menu - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 static void menu_wdata_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/mixmaster/chain_data.c b/mixmaster/chain_data.c
index de640fc83..c4b0aa77e 100644
--- a/mixmaster/chain_data.c
+++ b/mixmaster/chain_data.c
@@ -40,7 +40,7 @@ struct ChainData *chain_data_new(void)
 }
 
 /**
- * chain_data_free - Free the Chain data attached to the Window - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * chain_data_free - Free the Chain data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 void chain_data_free(struct MuttWindow *win, void **ptr)
 {
diff --git a/mixmaster/win_hosts.c b/mixmaster/win_hosts.c
index 0a3572620..b4990c38e 100644
--- a/mixmaster/win_hosts.c
+++ b/mixmaster/win_hosts.c
@@ -187,7 +187,7 @@ static const char *mix_format_str(char *buf, size_t buflen, size_t col, int cols
 }
 
 /**
- * mix_make_entry - Format a menu item for the mixmaster chain list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * mix_make_entry - Format a Remailer for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $mix_entry_format, mix_format_str()
  */
diff --git a/mutt/hash.c b/mutt/hash.c
index 47c63b18e..4f72094e7 100644
--- a/mutt/hash.c
+++ b/mutt/hash.c
@@ -37,7 +37,7 @@
 #define SOME_PRIME 149711
 
 /**
- * gen_string_hash - Generate a hash from a string - Implements hash_gen_hash_t - @ingroup hash_gen_hash_api
+ * gen_string_hash - Generate a hash from a string - Implements ::hash_gen_hash_t - @ingroup hash_gen_hash_api
  *
  * @note If the key is NULL or empty, the retval will be 0
  */
@@ -56,7 +56,7 @@ static size_t gen_string_hash(union HashKey key, size_t num_elems)
 }
 
 /**
- * cmp_string_key - Compare two string keys - Implements hash_cmp_key_t - @ingroup hash_cmp_key_api
+ * cmp_string_key - Compare two string keys - Implements ::hash_cmp_key_t - @ingroup hash_cmp_key_api
  */
 static int cmp_string_key(union HashKey a, union HashKey b)
 {
@@ -64,7 +64,7 @@ static int cmp_string_key(union HashKey a, union HashKey b)
 }
 
 /**
- * gen_case_string_hash - Generate a hash from a string (ignore the case) - Implements hash_gen_hash_t - @ingroup hash_gen_hash_api
+ * gen_case_string_hash - Generate a hash from a string (ignore the case) - Implements ::hash_gen_hash_t - @ingroup hash_gen_hash_api
  *
  * @note If the key is NULL or empty, the retval will be 0
  */
@@ -83,7 +83,7 @@ static size_t gen_case_string_hash(union HashKey key, size_t num_elems)
 }
 
 /**
- * cmp_case_string_key - Compare two string keys (ignore case) - Implements hash_cmp_key_t - @ingroup hash_cmp_key_api
+ * cmp_case_string_key - Compare two string keys (ignore case) - Implements ::hash_cmp_key_t - @ingroup hash_cmp_key_api
  */
 static int cmp_case_string_key(union HashKey a, union HashKey b)
 {
@@ -91,7 +91,7 @@ static int cmp_case_string_key(union HashKey a, union HashKey b)
 }
 
 /**
- * gen_int_hash - Generate a hash from an integer - Implements hash_gen_hash_t - @ingroup hash_gen_hash_api
+ * gen_int_hash - Generate a hash from an integer - Implements ::hash_gen_hash_t - @ingroup hash_gen_hash_api
  */
 static size_t gen_int_hash(union HashKey key, size_t num_elems)
 {
@@ -99,7 +99,7 @@ static size_t gen_int_hash(union HashKey key, size_t num_elems)
 }
 
 /**
- * cmp_int_key - Compare two integer keys - Implements hash_cmp_key_t - @ingroup hash_cmp_key_api
+ * cmp_int_key - Compare two integer keys - Implements ::hash_cmp_key_t - @ingroup hash_cmp_key_api
  */
 static int cmp_int_key(union HashKey a, union HashKey b)
 {
diff --git a/mutt_thread.c b/mutt_thread.c
index e3afc1432..bb1a2de1d 100644
--- a/mutt_thread.c
+++ b/mutt_thread.c
@@ -100,7 +100,7 @@ const char *get_use_threads_str(enum UseThreads value)
 }
 
 /**
- * sort_validator - Validate values of "sort" - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ * sort_validator - Validate the "sort" config variable - Implements ConfigDef::validator() - @ingroup cfg_def_validator
  */
 int sort_validator(const struct ConfigSet *cs, const struct ConfigDef *cdef,
                    intptr_t value, struct Buffer *err)
@@ -1013,7 +1013,7 @@ static void check_subjects(struct MailboxView *mv, bool init)
 }
 
 /**
- * thread_hash_destructor - Hash Destructor callback - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
+ * thread_hash_destructor - Free our hash table data - Implements ::hash_hdata_free_t - @ingroup hash_hdata_free_api
  */
 static void thread_hash_destructor(int type, void *obj, intptr_t data)
 {
diff --git a/ncrypt/crypt.c b/ncrypt/crypt.c
index ad4d43da3..bb344c0a6 100644
--- a/ncrypt/crypt.c
+++ b/ncrypt/crypt.c
@@ -1101,7 +1101,7 @@ bool mutt_should_hide_protected_subject(struct Email *e)
 }
 
 /**
- * mutt_protected_headers_handler - Process a protected header - Implements ::handler_t - @ingroup handler_api
+ * mutt_protected_headers_handler - Handler for protected headers - Implements ::handler_t - @ingroup handler_api
  */
 int mutt_protected_headers_handler(struct Body *b, struct State *state)
 {
@@ -1131,7 +1131,7 @@ int mutt_protected_headers_handler(struct Body *b, struct State *state)
 }
 
 /**
- * mutt_signed_handler - Verify a "multipart/signed" body - Implements ::handler_t - @ingroup handler_api
+ * mutt_signed_handler - Handler for "multipart/signed" - Implements ::handler_t - @ingroup handler_api
  */
 int mutt_signed_handler(struct Body *b, struct State *state)
 {
diff --git a/ncrypt/crypt_gpgme.c b/ncrypt/crypt_gpgme.c
index 24aa438e0..f43178ba0 100644
--- a/ncrypt/crypt_gpgme.c
+++ b/ncrypt/crypt_gpgme.c
@@ -1016,7 +1016,7 @@ static struct Body *sign_message(struct Body *a, const struct AddressList *from,
 }
 
 /**
- * pgp_gpgme_sign_message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
+ * pgp_gpgme_sign_message - Cryptographically sign the Body of a message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
  */
 struct Body *pgp_gpgme_sign_message(struct Body *a, const struct AddressList *from)
 {
@@ -1024,7 +1024,7 @@ struct Body *pgp_gpgme_sign_message(struct Body *a, const struct AddressList *fr
 }
 
 /**
- * smime_gpgme_sign_message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
+ * smime_gpgme_sign_message - Cryptographically sign the Body of a message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
  */
 struct Body *smime_gpgme_sign_message(struct Body *a, const struct AddressList *from)
 {
@@ -1032,7 +1032,7 @@ struct Body *smime_gpgme_sign_message(struct Body *a, const struct AddressList *
 }
 
 /**
- * pgp_gpgme_encrypt_message - Implements CryptModuleSpecs::pgp_encrypt_message() - @ingroup crypto_pgp_encrypt_message
+ * pgp_gpgme_encrypt_message - PGP encrypt an email - Implements CryptModuleSpecs::pgp_encrypt_message() - @ingroup crypto_pgp_encrypt_message
  */
 struct Body *pgp_gpgme_encrypt_message(struct Body *a, char *keylist, bool sign,
                                        const struct AddressList *from)
@@ -1078,7 +1078,7 @@ struct Body *pgp_gpgme_encrypt_message(struct Body *a, char *keylist, bool sign,
 }
 
 /**
- * smime_gpgme_build_smime_entity - Implements CryptModuleSpecs::smime_build_smime_entity() - @ingroup crypto_smime_build_smime_entity
+ * smime_gpgme_build_smime_entity - Encrypt the email body to all recipients - Implements CryptModuleSpecs::smime_build_smime_entity() - @ingroup crypto_smime_build_smime_entity
  */
 struct Body *smime_gpgme_build_smime_entity(struct Body *a, char *keylist)
 {
@@ -1663,7 +1663,7 @@ static int verify_one(struct Body *sigbdy, struct State *state,
 }
 
 /**
- * pgp_gpgme_verify_one - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
+ * pgp_gpgme_verify_one - Check a signed MIME part against a signature - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
  */
 int pgp_gpgme_verify_one(struct Body *sigbdy, struct State *state, const char *tempfile)
 {
@@ -1671,7 +1671,7 @@ int pgp_gpgme_verify_one(struct Body *sigbdy, struct State *state, const char *t
 }
 
 /**
- * smime_gpgme_verify_one - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
+ * smime_gpgme_verify_one - Check a signed MIME part against a signature - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
  */
 int smime_gpgme_verify_one(struct Body *sigbdy, struct State *state, const char *tempfile)
 {
@@ -1848,7 +1848,7 @@ cleanup:
 }
 
 /**
- * pgp_gpgme_decrypt_mime - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
+ * pgp_gpgme_decrypt_mime - Decrypt an encrypted MIME part - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
  */
 int pgp_gpgme_decrypt_mime(FILE *fp_in, FILE **fp_out, struct Body *b, struct Body **cur)
 {
@@ -1945,7 +1945,7 @@ bail:
 }
 
 /**
- * smime_gpgme_decrypt_mime - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
+ * smime_gpgme_decrypt_mime - Decrypt an encrypted MIME part - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
  */
 int smime_gpgme_decrypt_mime(FILE *fp_in, FILE **fp_out, struct Body *b, struct Body **cur)
 {
@@ -2231,7 +2231,7 @@ cleanup:
 }
 
 /**
- * pgp_gpgme_check_traditional - Implements CryptModuleSpecs::pgp_check_traditional() - @ingroup crypto_pgp_check_traditional
+ * pgp_gpgme_check_traditional - Look for inline (non-MIME) PGP content - Implements CryptModuleSpecs::pgp_check_traditional() - @ingroup crypto_pgp_check_traditional
  */
 bool pgp_gpgme_check_traditional(FILE *fp, struct Body *b, bool just_one)
 {
@@ -2258,7 +2258,7 @@ bool pgp_gpgme_check_traditional(FILE *fp, struct Body *b, bool just_one)
 }
 
 /**
- * pgp_gpgme_invoke_import - Implements CryptModuleSpecs::pgp_invoke_import() - @ingroup crypto_pgp_invoke_import
+ * pgp_gpgme_invoke_import - Import a key from a message into the user's public key ring - Implements CryptModuleSpecs::pgp_invoke_import() - @ingroup crypto_pgp_invoke_import
  */
 void pgp_gpgme_invoke_import(const char *fname)
 {
@@ -2423,7 +2423,7 @@ static void copy_clearsigned(gpgme_data_t data, struct State *state, char *chars
 }
 
 /**
- * pgp_gpgme_application_handler - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
+ * pgp_gpgme_application_handler - Manage the MIME type "application/pgp" or "application/smime" - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
  */
 int pgp_gpgme_application_handler(struct Body *m, struct State *state)
 {
@@ -2653,7 +2653,7 @@ int pgp_gpgme_application_handler(struct Body *m, struct State *state)
 }
 
 /**
- * pgp_gpgme_encrypted_handler - Implements CryptModuleSpecs::encrypted_handler() - @ingroup crypto_encrypted_handler
+ * pgp_gpgme_encrypted_handler - Manage a PGP or S/MIME encrypted MIME part - Implements CryptModuleSpecs::encrypted_handler() - @ingroup crypto_encrypted_handler
  *
  * This handler is passed the application/octet-stream directly.
  * The caller must propagate a->goodsig to its parent.
@@ -2747,7 +2747,7 @@ int pgp_gpgme_encrypted_handler(struct Body *a, struct State *state)
 }
 
 /**
- * smime_gpgme_application_handler - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
+ * smime_gpgme_application_handler - Manage the MIME type "application/pgp" or "application/smime" - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
  */
 int smime_gpgme_application_handler(struct Body *a, struct State *state)
 {
@@ -3539,7 +3539,7 @@ static char *find_keys(const struct AddressList *addrlist, unsigned int app, boo
 }
 
 /**
- * pgp_gpgme_find_keys - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
+ * pgp_gpgme_find_keys - Find the keyids of the recipients of a message - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
  */
 char *pgp_gpgme_find_keys(const struct AddressList *addrlist, bool oppenc_mode)
 {
@@ -3547,7 +3547,7 @@ char *pgp_gpgme_find_keys(const struct AddressList *addrlist, bool oppenc_mode)
 }
 
 /**
- * smime_gpgme_find_keys - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
+ * smime_gpgme_find_keys - Find the keyids of the recipients of a message - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
  */
 char *smime_gpgme_find_keys(const struct AddressList *addrlist, bool oppenc_mode)
 {
@@ -3646,7 +3646,7 @@ cleanup:
 #endif
 
 /**
- * pgp_gpgme_make_key_attachment - Implements CryptModuleSpecs::pgp_make_key_attachment() - @ingroup crypto_pgp_make_key_attachment
+ * pgp_gpgme_make_key_attachment - Generate a public key attachment - Implements CryptModuleSpecs::pgp_make_key_attachment() - @ingroup crypto_pgp_make_key_attachment
  */
 struct Body *pgp_gpgme_make_key_attachment(void)
 {
@@ -3746,7 +3746,7 @@ static void init_smime(void)
 }
 
 /**
- * pgp_gpgme_init - Implements CryptModuleSpecs::init() - @ingroup crypto_init
+ * pgp_gpgme_init - Initialise the crypto module - Implements CryptModuleSpecs::init() - @ingroup crypto_init
  */
 void pgp_gpgme_init(void)
 {
@@ -3755,7 +3755,7 @@ void pgp_gpgme_init(void)
 }
 
 /**
- * smime_gpgme_init - Implements CryptModuleSpecs::init() - @ingroup crypto_init
+ * smime_gpgme_init - Initialise the crypto module - Implements CryptModuleSpecs::init() - @ingroup crypto_init
  */
 void smime_gpgme_init(void)
 {
@@ -3928,7 +3928,7 @@ static SecurityFlags gpgme_send_menu(struct Email *e, bool is_smime)
 }
 
 /**
- * pgp_gpgme_send_menu - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
+ * pgp_gpgme_send_menu - Ask the user whether to sign and/or encrypt the email - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
  */
 SecurityFlags pgp_gpgme_send_menu(struct Email *e)
 {
@@ -3936,7 +3936,7 @@ SecurityFlags pgp_gpgme_send_menu(struct Email *e)
 }
 
 /**
- * smime_gpgme_send_menu - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
+ * smime_gpgme_send_menu - Ask the user whether to sign and/or encrypt the email - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
  */
 SecurityFlags smime_gpgme_send_menu(struct Email *e)
 {
@@ -4025,7 +4025,7 @@ static bool verify_sender(struct Email *e)
 }
 
 /**
- * smime_gpgme_verify_sender - Implements CryptModuleSpecs::smime_verify_sender() - @ingroup crypto_smime_verify_sender
+ * smime_gpgme_verify_sender - Does the sender match the certificate? - Implements CryptModuleSpecs::smime_verify_sender() - @ingroup crypto_smime_verify_sender
  */
 int smime_gpgme_verify_sender(struct Email *e, struct Message *msg)
 {
@@ -4033,7 +4033,7 @@ int smime_gpgme_verify_sender(struct Email *e, struct Message *msg)
 }
 
 /**
- * pgp_gpgme_set_sender - Implements CryptModuleSpecs::set_sender() - @ingroup crypto_set_sender
+ * pgp_gpgme_set_sender - Set the sender of the email - Implements CryptModuleSpecs::set_sender() - @ingroup crypto_set_sender
  */
 void pgp_gpgme_set_sender(const char *sender)
 {
diff --git a/ncrypt/crypt_mod_pgp_classic.c b/ncrypt/crypt_mod_pgp_classic.c
index 4359eacd6..d88cb3a12 100644
--- a/ncrypt/crypt_mod_pgp_classic.c
+++ b/ncrypt/crypt_mod_pgp_classic.c
@@ -37,7 +37,7 @@
 #endif
 
 /**
- * CryptModPgpClassic - CLI PGP - Implements ::CryptModuleSpecs
+ * CryptModPgpClassic - CLI PGP - Implements ::CryptModuleSpecs - @ingroup crypto_api
  */
 const struct CryptModuleSpecs CryptModPgpClassic = {
   // clang-format off
diff --git a/ncrypt/crypt_mod_pgp_gpgme.c b/ncrypt/crypt_mod_pgp_gpgme.c
index e689983a7..dd9c62836 100644
--- a/ncrypt/crypt_mod_pgp_gpgme.c
+++ b/ncrypt/crypt_mod_pgp_gpgme.c
@@ -34,7 +34,7 @@
 #include "crypt_mod.h"
 
 /**
- * pgp_gpgme_void_passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
+ * pgp_gpgme_void_passphrase - Forget the cached passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
  *
  * This is handled by gpg-agent.
  */
@@ -43,7 +43,7 @@ static void pgp_gpgme_void_passphrase(void)
 }
 
 /**
- * pgp_gpgme_valid_passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
+ * pgp_gpgme_valid_passphrase - Ensure we have a valid passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
  *
  * This is handled by gpg-agent.
  */
@@ -53,7 +53,7 @@ static bool pgp_gpgme_valid_passphrase(void)
 }
 
 /**
- * CryptModPgpGpgme - GPGME PGP - Implements ::CryptModuleSpecs
+ * CryptModPgpGpgme - GPGME PGP - Implements ::CryptModuleSpecs - @ingroup crypto_api
  */
 const struct CryptModuleSpecs CryptModPgpGpgme = {
   // clang-format off
diff --git a/ncrypt/crypt_mod_smime_classic.c b/ncrypt/crypt_mod_smime_classic.c
index 8ba28da9f..efe3f4908 100644
--- a/ncrypt/crypt_mod_smime_classic.c
+++ b/ncrypt/crypt_mod_smime_classic.c
@@ -51,7 +51,7 @@ static void smime_class_cleanup(void)
 }
 
 /**
- * CryptModSmimeClassic - CLI SMIME - Implements ::CryptModuleSpecs
+ * CryptModSmimeClassic - CLI SMIME - Implements ::CryptModuleSpecs - @ingroup crypto_api
  */
 const struct CryptModuleSpecs CryptModSmimeClassic = {
   // clang-format off
diff --git a/ncrypt/crypt_mod_smime_gpgme.c b/ncrypt/crypt_mod_smime_gpgme.c
index 620a05431..5407fc7cb 100644
--- a/ncrypt/crypt_mod_smime_gpgme.c
+++ b/ncrypt/crypt_mod_smime_gpgme.c
@@ -34,7 +34,7 @@
 #include "crypt_mod.h"
 
 /**
- * smime_gpgme_void_passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
+ * smime_gpgme_void_passphrase - Forget the cached passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
  *
  * This is handled by gpg-agent.
  */
@@ -43,7 +43,7 @@ static void smime_gpgme_void_passphrase(void)
 }
 
 /**
- * smime_gpgme_valid_passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
+ * smime_gpgme_valid_passphrase - Ensure we have a valid passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
  *
  * This is handled by gpg-agent.
  */
@@ -53,7 +53,7 @@ static bool smime_gpgme_valid_passphrase(void)
 }
 
 /**
- * CryptModSmimeGpgme - GPGME SMIME - Implements ::CryptModuleSpecs
+ * CryptModSmimeGpgme - GPGME SMIME - Implements ::CryptModuleSpecs - @ingroup crypto_api
  */
 const struct CryptModuleSpecs CryptModSmimeGpgme = {
   // clang-format off
diff --git a/ncrypt/dlg_gpgme.c b/ncrypt/dlg_gpgme.c
index 0d6329c7a..67d6a1c7d 100644
--- a/ncrypt/dlg_gpgme.c
+++ b/ncrypt/dlg_gpgme.c
@@ -535,7 +535,7 @@ static const char *crypt_format_str(char *buf, size_t buflen, size_t col, int co
 }
 
 /**
- * crypt_make_entry - Format a menu item for the key selection list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * crypt_make_entry - Format a PGP Key for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $pgp_entry_format, crypt_format_str()
  */
diff --git a/ncrypt/dlg_pgp.c b/ncrypt/dlg_pgp.c
index 466dc030c..44f8a5d72 100644
--- a/ncrypt/dlg_pgp.c
+++ b/ncrypt/dlg_pgp.c
@@ -445,7 +445,7 @@ static const char *pgp_entry_format_str(char *buf, size_t buflen, size_t col, in
 }
 
 /**
- * pgp_make_entry - Format a menu item for the pgp key list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * pgp_make_entry - Format a PGP Key for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $pgp_entry_format, pgp_entry_format_str()
  */
diff --git a/ncrypt/dlg_smime.c b/ncrypt/dlg_smime.c
index e02a25aa5..671416cc7 100644
--- a/ncrypt/dlg_smime.c
+++ b/ncrypt/dlg_smime.c
@@ -105,7 +105,7 @@ static char *smime_key_flags(KeyFlags flags)
 }
 
 /**
- * smime_make_entry - Format a menu item for the smime key list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * smime_make_entry - Format an S/MIME Key for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  */
 static void smime_make_entry(struct Menu *menu, char *buf, size_t buflen, int line)
 {
diff --git a/ncrypt/pgp.c b/ncrypt/pgp.c
index b4d54ea01..7ea5d357b 100644
--- a/ncrypt/pgp.c
+++ b/ncrypt/pgp.c
@@ -72,7 +72,7 @@ static char PgpPass[1024];
 static time_t PgpExptime = 0; /* when does the cached passphrase expire? */
 
 /**
- * pgp_class_void_passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
+ * pgp_class_void_passphrase - Forget the cached passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
  */
 void pgp_class_void_passphrase(void)
 {
@@ -81,7 +81,7 @@ void pgp_class_void_passphrase(void)
 }
 
 /**
- * pgp_class_valid_passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
+ * pgp_class_valid_passphrase - Ensure we have a valid passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
  */
 bool pgp_class_valid_passphrase(void)
 {
@@ -468,7 +468,7 @@ static void pgp_copy_clearsigned(FILE *fp_in, struct State *state, char *charset
 }
 
 /**
- * pgp_class_application_handler - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
+ * pgp_class_application_handler - Manage the MIME type "application/pgp" or "application/smime" - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
  */
 int pgp_class_application_handler(struct Body *m, struct State *state)
 {
@@ -866,7 +866,7 @@ cleanup:
 }
 
 /**
- * pgp_class_check_traditional - Implements CryptModuleSpecs::pgp_check_traditional() - @ingroup crypto_pgp_check_traditional
+ * pgp_class_check_traditional - Look for inline (non-MIME) PGP content - Implements CryptModuleSpecs::pgp_check_traditional() - @ingroup crypto_pgp_check_traditional
  */
 bool pgp_class_check_traditional(FILE *fp, struct Body *b, bool just_one)
 {
@@ -895,7 +895,7 @@ bool pgp_class_check_traditional(FILE *fp, struct Body *b, bool just_one)
 }
 
 /**
- * pgp_class_verify_one - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
+ * pgp_class_verify_one - Check a signed MIME part against a signature - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
  */
 int pgp_class_verify_one(struct Body *sigbdy, struct State *state, const char *tempfile)
 {
@@ -1000,7 +1000,7 @@ cleanup:
 }
 
 /**
- * pgp_class_extract_key_from_attachment - Implements CryptModuleSpecs::pgp_extract_key_from_attachment() - @ingroup crypto_pgp_extract_key_from_attachment
+ * pgp_class_extract_key_from_attachment - Extract PGP key from an attachment - Implements CryptModuleSpecs::pgp_extract_key_from_attachment() - @ingroup crypto_pgp_extract_key_from_attachment
  */
 void pgp_class_extract_key_from_attachment(FILE *fp, struct Body *top)
 {
@@ -1159,7 +1159,7 @@ cleanup:
 }
 
 /**
- * pgp_class_decrypt_mime - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
+ * pgp_class_decrypt_mime - Decrypt an encrypted MIME part - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
  */
 int pgp_class_decrypt_mime(FILE *fp_in, FILE **fp_out, struct Body *b, struct Body **cur)
 {
@@ -1244,7 +1244,7 @@ bail:
 }
 
 /**
- * pgp_class_encrypted_handler - Implements CryptModuleSpecs::encrypted_handler() - @ingroup crypto_encrypted_handler
+ * pgp_class_encrypted_handler - Manage a PGP or S/MIME encrypted MIME part - Implements CryptModuleSpecs::encrypted_handler() - @ingroup crypto_encrypted_handler
  */
 int pgp_class_encrypted_handler(struct Body *a, struct State *state)
 {
@@ -1332,7 +1332,7 @@ int pgp_class_encrypted_handler(struct Body *a, struct State *state)
  */
 
 /**
- * pgp_class_sign_message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
+ * pgp_class_sign_message - Cryptographically sign the Body of a message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
  */
 struct Body *pgp_class_sign_message(struct Body *a, const struct AddressList *from)
 {
@@ -1463,7 +1463,7 @@ cleanup:
 }
 
 /**
- * pgp_class_find_keys - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
+ * pgp_class_find_keys - Find the keyids of the recipients of a message - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
  */
 char *pgp_class_find_keys(const struct AddressList *addrlist, bool oppenc_mode)
 {
@@ -1584,7 +1584,7 @@ char *pgp_class_find_keys(const struct AddressList *addrlist, bool oppenc_mode)
 }
 
 /**
- * pgp_class_encrypt_message - Implements CryptModuleSpecs::pgp_encrypt_message() - @ingroup crypto_pgp_encrypt_message
+ * pgp_class_encrypt_message - PGP encrypt an email - Implements CryptModuleSpecs::pgp_encrypt_message() - @ingroup crypto_pgp_encrypt_message
  *
  * @warning "a" is no longer freed in this routine, you need to free it later.
  * This is necessary for $fcc_attach.
@@ -1721,7 +1721,7 @@ cleanup:
 }
 
 /**
- * pgp_class_traditional_encryptsign - Implements CryptModuleSpecs::pgp_traditional_encryptsign() - @ingroup crypto_pgp_traditional_encryptsign
+ * pgp_class_traditional_encryptsign - Create an inline PGP encrypted, signed email - Implements CryptModuleSpecs::pgp_traditional_encryptsign() - @ingroup crypto_pgp_traditional_encryptsign
  */
 struct Body *pgp_class_traditional_encryptsign(struct Body *a, SecurityFlags flags, char *keylist)
 {
@@ -1893,7 +1893,7 @@ cleanup:
 }
 
 /**
- * pgp_class_send_menu - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
+ * pgp_class_send_menu - Ask the user whether to sign and/or encrypt the email - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
  */
 SecurityFlags pgp_class_send_menu(struct Email *e)
 {
diff --git a/ncrypt/pgpinvoke.c b/ncrypt/pgpinvoke.c
index cbf4a726f..69e0b9d57 100644
--- a/ncrypt/pgpinvoke.c
+++ b/ncrypt/pgpinvoke.c
@@ -414,7 +414,7 @@ pid_t pgp_invoke_traditional(FILE **fp_pgp_in, FILE **fp_pgp_out, FILE **fp_pgp_
 }
 
 /**
- * pgp_class_invoke_import - Implements CryptModuleSpecs::pgp_invoke_import() - @ingroup crypto_pgp_invoke_import
+ * pgp_class_invoke_import - Import a key from a message into the user's public key ring - Implements CryptModuleSpecs::pgp_invoke_import() - @ingroup crypto_pgp_invoke_import
  */
 void pgp_class_invoke_import(const char *fname)
 {
@@ -441,7 +441,7 @@ void pgp_class_invoke_import(const char *fname)
 }
 
 /**
- * pgp_class_invoke_getkeys - Implements CryptModuleSpecs::pgp_invoke_getkeys() - @ingroup crypto_pgp_invoke_getkeys
+ * pgp_class_invoke_getkeys - Run a command to download a PGP key - Implements CryptModuleSpecs::pgp_invoke_getkeys() - @ingroup crypto_pgp_invoke_getkeys
  */
 void pgp_class_invoke_getkeys(struct Address *addr)
 {
diff --git a/ncrypt/pgpkey.c b/ncrypt/pgpkey.c
index 5282d483e..fd4da7ddc 100644
--- a/ncrypt/pgpkey.c
+++ b/ncrypt/pgpkey.c
@@ -235,7 +235,7 @@ done:
 }
 
 /**
- * pgp_class_make_key_attachment - Implements CryptModuleSpecs::pgp_make_key_attachment() - @ingroup crypto_pgp_make_key_attachment
+ * pgp_class_make_key_attachment - Generate a public key attachment - Implements CryptModuleSpecs::pgp_make_key_attachment() - @ingroup crypto_pgp_make_key_attachment
  */
 struct Body *pgp_class_make_key_attachment(void)
 {
diff --git a/ncrypt/smime.c b/ncrypt/smime.c
index e1ce60c96..c54614f8d 100644
--- a/ncrypt/smime.c
+++ b/ncrypt/smime.c
@@ -161,7 +161,7 @@ static struct SmimeKey *smime_copy_key(struct SmimeKey *key)
  */
 
 /**
- * smime_class_void_passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
+ * smime_class_void_passphrase - Forget the cached passphrase - Implements CryptModuleSpecs::void_passphrase() - @ingroup crypto_void_passphrase
  */
 void smime_class_void_passphrase(void)
 {
@@ -170,7 +170,7 @@ void smime_class_void_passphrase(void)
 }
 
 /**
- * smime_class_valid_passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
+ * smime_class_valid_passphrase - Ensure we have a valid passphrase - Implements CryptModuleSpecs::valid_passphrase() - @ingroup crypto_valid_passphrase
  */
 bool smime_class_valid_passphrase(void)
 {
@@ -809,7 +809,7 @@ static void getkeys(const char *mailbox)
 }
 
 /**
- * smime_class_getkeys - Implements CryptModuleSpecs::smime_getkeys() - @ingroup crypto_smime_getkeys
+ * smime_class_getkeys - Get the S/MIME keys required to encrypt this email - Implements CryptModuleSpecs::smime_getkeys() - @ingroup crypto_smime_getkeys
  */
 void smime_class_getkeys(struct Envelope *env)
 {
@@ -849,7 +849,7 @@ void smime_class_getkeys(struct Envelope *env)
 }
 
 /**
- * smime_class_find_keys - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
+ * smime_class_find_keys - Find the keyids of the recipients of a message - Implements CryptModuleSpecs::find_keys() - @ingroup crypto_find_keys
  */
 char *smime_class_find_keys(const struct AddressList *al, bool oppenc_mode)
 {
@@ -1179,7 +1179,7 @@ cleanup:
 }
 
 /**
- * smime_class_invoke_import - Implements CryptModuleSpecs::smime_invoke_import() - @ingroup crypto_smime_invoke_import
+ * smime_class_invoke_import - Add a certificate and update index file (externally) - Implements CryptModuleSpecs::smime_invoke_import() - @ingroup crypto_smime_invoke_import
  */
 void smime_class_invoke_import(const char *infile, const char *mailbox)
 {
@@ -1253,7 +1253,7 @@ done:
 }
 
 /**
- * smime_class_verify_sender - Implements CryptModuleSpecs::smime_verify_sender() - @ingroup crypto_smime_verify_sender
+ * smime_class_verify_sender - Does the sender match the certificate? - Implements CryptModuleSpecs::smime_verify_sender() - @ingroup crypto_smime_verify_sender
  */
 int smime_class_verify_sender(struct Email *e, struct Message *msg)
 {
@@ -1379,7 +1379,7 @@ static pid_t smime_invoke_sign(FILE **fp_smime_in, FILE **fp_smime_out,
 }
 
 /**
- * smime_class_build_smime_entity - Implements CryptModuleSpecs::smime_build_smime_entity() - @ingroup crypto_smime_build_smime_entity
+ * smime_class_build_smime_entity - Encrypt the email body to all recipients - Implements CryptModuleSpecs::smime_build_smime_entity() - @ingroup crypto_smime_build_smime_entity
  */
 struct Body *smime_class_build_smime_entity(struct Body *a, char *certlist)
 {
@@ -1542,7 +1542,7 @@ static char *openssl_md_to_smime_micalg(const char *md)
 }
 
 /**
- * smime_class_sign_message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
+ * smime_class_sign_message - Cryptographically sign the Body of a message - Implements CryptModuleSpecs::sign_message() - @ingroup crypto_sign_message
  */
 struct Body *smime_class_sign_message(struct Body *a, const struct AddressList *from)
 {
@@ -1750,7 +1750,7 @@ static pid_t smime_invoke_decrypt(FILE **fp_smime_in, FILE **fp_smime_out,
 }
 
 /**
- * smime_class_verify_one - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
+ * smime_class_verify_one - Check a signed MIME part against a signature - Implements CryptModuleSpecs::verify_one() - @ingroup crypto_verify_one
  */
 int smime_class_verify_one(struct Body *sigbdy, struct State *state, const char *tempfile)
 {
@@ -2102,7 +2102,7 @@ cleanup:
 }
 
 /**
- * smime_class_decrypt_mime - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
+ * smime_class_decrypt_mime - Decrypt an encrypted MIME part - Implements CryptModuleSpecs::decrypt_mime() - @ingroup crypto_decrypt_mime
  */
 int smime_class_decrypt_mime(FILE *fp_in, FILE **fp_out, struct Body *b, struct Body **cur)
 {
@@ -2165,7 +2165,7 @@ bail:
 }
 
 /**
- * smime_class_application_handler - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
+ * smime_class_application_handler - Manage the MIME type "application/pgp" or "application/smime" - Implements CryptModuleSpecs::application_handler() - @ingroup crypto_application_handler
  */
 int smime_class_application_handler(struct Body *m, struct State *state)
 {
@@ -2184,7 +2184,7 @@ int smime_class_application_handler(struct Body *m, struct State *state)
 }
 
 /**
- * smime_class_send_menu - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
+ * smime_class_send_menu - Ask the user whether to sign and/or encrypt the email - Implements CryptModuleSpecs::send_menu() - @ingroup crypto_send_menu
  */
 SecurityFlags smime_class_send_menu(struct Email *e)
 {
diff --git a/nntp/adata.c b/nntp/adata.c
index aa6c0c8eb..9ce40cd64 100644
--- a/nntp/adata.c
+++ b/nntp/adata.c
@@ -34,7 +34,7 @@
 struct Connection;
 
 /**
- * nntp_adata_free - Free the private Account data - Implements Account::adata_free()
+ * nntp_adata_free - Free the private Account data - Implements Account::adata_free() - @ingroup account_adata_free
  *
  * The NntpAccountData struct stores global NNTP data, such as the connection to
  * the database.  This function will close the database, free the resources and
diff --git a/nntp/edata.c b/nntp/edata.c
index f286e0d20..be5138a4b 100644
--- a/nntp/edata.c
+++ b/nntp/edata.c
@@ -33,7 +33,7 @@
 #include "edata.h"
 
 /**
- * nntp_edata_free - Free the private Email data - Implements Email::edata_free()
+ * nntp_edata_free - Free the private Email data - Implements Email::edata_free() - @ingroup email_edata_free
  */
 void nntp_edata_free(void **ptr)
 {
diff --git a/nntp/mdata.c b/nntp/mdata.c
index 623e810f4..a679a4de1 100644
--- a/nntp/mdata.c
+++ b/nntp/mdata.c
@@ -33,7 +33,7 @@
 #include "bcache/lib.h"
 
 /**
- * nntp_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free()
+ * nntp_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free() - @ingroup mailbox_mdata_free
  */
 void nntp_mdata_free(void **ptr)
 {
diff --git a/nntp/newsrc.c b/nntp/newsrc.c
index cbb83d9cc..14f105178 100644
--- a/nntp/newsrc.c
+++ b/nntp/newsrc.c
@@ -779,7 +779,7 @@ void nntp_hcache_update(struct NntpMboxData *mdata, struct HeaderCache *hc)
 #endif
 
 /**
- * nntp_bcache_delete - Remove bcache file - Implements ::bcache_list_t - @ingroup bcache_list_api
+ * nntp_bcache_delete - Delete an entry from the message cache - Implements ::bcache_list_t - @ingroup bcache_list_api
  * @retval 0 Always
  */
 static int nntp_bcache_delete(const char *id, struct BodyCache *bcache, void *data)
@@ -985,7 +985,7 @@ const char *nntp_format_str(char *buf, size_t buflen, size_t col, int cols, char
 }
 
 /**
- * nntp_get_field - Get connection login credentials - Implements ConnAccount::get_field()
+ * nntp_get_field - Get connection login credentials - Implements ConnAccount::get_field() - @ingroup conn_account_get_field
  */
 static const char *nntp_get_field(enum ConnAccountField field, void *gf_data)
 {
diff --git a/nntp/nntp.c b/nntp/nntp.c
index 71fc454b8..3c98d327f 100644
--- a/nntp/nntp.c
+++ b/nntp/nntp.c
@@ -2300,7 +2300,7 @@ int nntp_check_children(struct Mailbox *m, const char *msgid)
 }
 
 /**
- * nntp_compare_order - Sort to mailbox order - Implements ::sort_mail_t - @ingroup sort_mail_api
+ * nntp_compare_order - Restore the 'unsorted' order of emails - Implements ::sort_mail_t - @ingroup sort_mail_api
  */
 int nntp_compare_order(const struct Email *a, const struct Email *b, bool reverse)
 {
diff --git a/notmuch/adata.c b/notmuch/adata.c
index 0e7cb2c07..17afad013 100644
--- a/notmuch/adata.c
+++ b/notmuch/adata.c
@@ -34,7 +34,7 @@
 #include "adata.h"
 
 /**
- * nm_adata_free - Free the private Account data - Implements Account::adata_free()
+ * nm_adata_free - Free the private Account data - Implements Account::adata_free() - @ingroup account_adata_free
  */
 void nm_adata_free(void **ptr)
 {
diff --git a/notmuch/config.c b/notmuch/config.c
index 72aa7df10..71ab3b195 100644
--- a/notmuch/config.c
+++ b/notmuch/config.c
@@ -49,7 +49,9 @@ static bool is_valid_notmuch_url(const char *url)
 #endif
 
 /**
- * nm_default_url_validator - Ensure nm_default_url is of the form notmuch://[absolute path] - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ * nm_default_url_validator - Validate the "nm_default_url" config variable - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ *
+ * Ensure nm_default_url is of the form notmuch://[absolute path]
  */
 static int nm_default_url_validator(const struct ConfigSet *cs, const struct ConfigDef *cdef,
                                     intptr_t value, struct Buffer *err)
@@ -66,7 +68,7 @@ static int nm_default_url_validator(const struct ConfigSet *cs, const struct Con
 }
 
 /**
- * nm_query_window_timebase_validator - Validate $nm_query_window_timebase - Implements ConfigDef::validator() - @ingroup cfg_def_validator
+ * nm_query_window_timebase_validator - Validate the "nm_query_window_timebase" config variable - Implements ConfigDef::validator() - @ingroup cfg_def_validator
  *
  * Ensure $nm_query_window_timebase matches allowed values.
  *
diff --git a/notmuch/mdata.c b/notmuch/mdata.c
index cb1fe9b8a..0ad9a1d05 100644
--- a/notmuch/mdata.c
+++ b/notmuch/mdata.c
@@ -36,7 +36,7 @@
 #include "query.h"
 
 /**
- * nm_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free()
+ * nm_mdata_free - Free the private Mailbox data - Implements Mailbox::mdata_free() - @ingroup mailbox_mdata_free
  *
  * The NmMboxData struct stores global Notmuch data, such as the connection to
  * the database.  This function will close the database, free the resources and
diff --git a/pager/pbar.c b/pager/pbar.c
index c3d0dbe4e..cea140465 100644
--- a/pager/pbar.c
+++ b/pager/pbar.c
@@ -293,7 +293,7 @@ static int pbar_window_observer(struct NotifyCallback *nc)
 }
 
 /**
- * pbar_data_free - Free the private data attached to the MuttWindow - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
+ * pbar_data_free - Free the private data - Implements MuttWindow::wdata_free() - @ingroup window_wdata_free
  */
 static void pbar_data_free(struct MuttWindow *win, void **ptr)
 {
@@ -308,7 +308,7 @@ static void pbar_data_free(struct MuttWindow *win, void **ptr)
 }
 
 /**
- * pbar_data_new - Free the private data attached to the MuttWindow
+ * pbar_data_new - Create new private data
  * @param shared Shared Index data
  * @param priv   Private Index data
  * @retval ptr New PBar
diff --git a/pattern/dlg_pattern.c b/pattern/dlg_pattern.c
index 11729959c..4a1160fff 100644
--- a/pattern/dlg_pattern.c
+++ b/pattern/dlg_pattern.c
@@ -131,7 +131,7 @@ static const char *pattern_format_str(char *buf, size_t buflen, size_t col, int
 }
 
 /**
- * make_pattern_entry - Create a line for the Pattern Completion menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * make_pattern_entry - Create a Pattern for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
  *
  * @sa $pattern_format, pattern_format_str()
  */
diff --git a/pop/adata.c b/pop/adata.c
index 643d03467..09b68055c 100644
--- a/pop/adata.c
+++ b/pop/adata.c
@@ -32,7 +32,7 @@
 #include "adata.h"
 
 /**
- * pop_adata_free - Free the private Account data - Implements Account::adata_free()
+ * pop_adata_free - Free the private Account data - Implements Account::adata_free() - @ingroup account_adata_free
  *
  * The PopAccountData struct stores global POP data, such as the connection to
  * the database.  This function will close the database, free the resources and
diff --git a/pop/auth.c b/pop/auth.c
index 4e89c0f76..82ae30a7c 100644
--- a/pop/auth.c
+++ b/pop/auth.c
@@ -48,7 +48,7 @@
 
 #ifdef USE_SASL_GNU
 /**
- * pop_auth_gsasl - POP GNU SASL authenticator - Implements PopAuth::authenticate()
+ * pop_auth_gsasl - POP GNU SASL authenticator - Implements PopAuth::authenticate() - @ingroup pop_authenticate
  */
 static enum PopAuthRes pop_auth_gsasl(struct PopAccountData *adata, const char *method)
 {
@@ -140,7 +140,7 @@ fail:
 
 #ifdef USE_SASL_CYRUS
 /**
- * pop_auth_sasl - POP SASL authenticator - Implements PopAuth::authenticate()
+ * pop_auth_sasl - POP SASL authenticator - Implements PopAuth::authenticate() - @ingroup pop_authenticate
  */
 static enum PopAuthRes pop_auth_sasl(struct PopAccountData *adata, const char *method)
 {
@@ -310,7 +310,7 @@ void pop_apop_timestamp(struct PopAccountData *adata, char *buf)
 }
 
 /**
- * pop_auth_apop - APOP authenticator - Implements PopAuth::authenticate()
+ * pop_auth_apop - APOP authenticator - Implements PopAuth::authenticate() - @ingroup pop_authenticate
  */
 static enum PopAuthRes pop_auth_apop(struct PopAccountData *adata, const char *method)
 {
@@ -359,7 +359,7 @@ static enum PopAuthRes pop_auth_apop(struct PopAccountData *adata, const char *m
 }
 
 /**
- * pop_auth_user - USER authenticator - Implements PopAuth::authenticate()
+ * pop_auth_user - USER authenticator - Implements PopAuth::authenticate() - @ingroup pop_authenticate
  */
 static enum PopAuthRes pop_auth_user(struct PopAccountData *adata, const char *method)
 {
@@ -417,7 +417,7 @@ static enum PopAuthRes pop_auth_user(struct PopAccountData *adata, const char *m
 }
 
 /**
- * pop_auth_oauth - Authenticate a POP connection using OAUTHBEARER - Implements PopAuth::authenticate()
+ * pop_auth_oauth - Authenticate a POP connection using OAUTHBEARER - Implements PopAuth::authenticate() - @ingroup pop_authenticate
  */
 static enum PopAuthRes pop_auth_oauth(struct PopAccountData *adata, const char *method)
 {
diff --git a/pop/edata.c b/pop/edata.c
index 75f56d1a9..eeead885c 100644
--- a/pop/edata.c
+++ b/pop/edata.c
@@ -33,7 +33,7 @@
 #include "edata.h"
 
 /**
- * pop_edata_free - Free the private Email data - Implements Email::edata_free()
+ * pop_edata_free - Free the private Email data - Implements Email::edata_free() - @ingroup email_edata_free
  *
  * Each email has an attached PopEmailData, which contains things like the tags
  * (labels).
diff --git a/pop/lib.c b/pop/lib.c
index df3d1e0da..a1e24e828 100644
--- a/pop/lib.c
+++ b/pop/lib.c
@@ -51,7 +51,7 @@
 struct Progress;
 
 /**
- * pop_get_field - Get connection login credentials - Implements ConnAccount::get_field()
+ * pop_get_field - Get connection login credentials - Implements ConnAccount::get_field() - @ingroup conn_account_get_field
  */
 const char *pop_get_field(enum ConnAccountField field, void *gf_data)
 {
@@ -138,7 +138,7 @@ static void pop_error(struct PopAccountData *adata, char *msg)
 }
 
 /**
- * fetch_capa - Parse CAPA output - Implements ::pop_fetch_t - @ingroup pop_fetch_api
+ * fetch_capa - Parse CAPA response - Implements ::pop_fetch_t - @ingroup pop_fetch_api
  * @param line List of capabilities
  * @param data POP data
  * @retval 0 (always)
@@ -173,7 +173,7 @@ static int fetch_capa(const char *line, void *data)
 }
 
 /**
- * fetch_auth - Fetch list of the authentication mechanisms - Implements ::pop_fetch_t - @ingroup pop_fetch_api
+ * fetch_auth - Parse AUTH response - Implements ::pop_fetch_t - @ingroup pop_fetch_api
  * @param line List of authentication methods
  * @param data POP data
  * @retval 0 (always)
@@ -563,11 +563,13 @@ int pop_fetch_data(struct PopAccountData *adata, const char *query,
 }
 
 /**
- * check_uidl - Find message with this UIDL and set refno - Implements ::pop_fetch_t - @ingroup pop_fetch_api
+ * check_uidl - Parse UIDL response - Implements ::pop_fetch_t - @ingroup pop_fetch_api
  * @param line String containing UIDL
  * @param data POP data
  * @retval  0 Success
  * @retval -1 Error
+ *
+ * Find message with this UIDL and set refno.
  */
 static int check_uidl(const char *line, void *data)
 {
diff --git a/pop/pop.c b/pop/pop.c
index ac7aee23f..19c2ed272 100644
--- a/pop/pop.c
+++ b/pop/pop.c
@@ -88,11 +88,13 @@ static const char *cache_id(const char *id)
 }
 
 /**
- * fetch_message - Write line to file - Implements ::pop_fetch_t - @ingroup pop_fetch_api
+ * fetch_message - Parse a Message response - Implements ::pop_fetch_t - @ingroup pop_fetch_api
  * @param line String to write
  * @param data FILE pointer to write to
  * @retval  0 Success
  * @retval -1 Failure
+ *
+ * Save a Message to a file.
  */
 static int fetch_message(const char *line, void *data)
 {
@@ -191,7 +193,7 @@ static int pop_read_header(struct PopAccountData *adata, struct Email *e)
 }
 
 /**
- * fetch_uidl - Parse UIDL - Implements ::pop_fetch_t - @ingroup pop_fetch_api
+ * fetch_uidl - Parse UIDL response - Implements ::pop_fetch_t - @ingroup pop_fetch_api
  * @param line String to parse
  * @param data Mailbox
  * @retval  0 Success
@@ -249,9 +251,9 @@ static int fetch_uidl(const char *line, void *data)
 }
 
 /**
- * msg_cache_check - Check the Body Cache for an ID - Implements ::bcache_list_t - @ingroup bcache_list_api
+ * pop_bcache_delete - Delete an entry from the message cache - Implements ::bcache_list_t - @ingroup bcache_list_api
  */
-static int msg_cache_check(const char *id, struct BodyCache *bcache, void *data)
+static int pop_bcache_delete(const char *id, struct BodyCache *bcache, void *data)
 {
   struct Mailbox *m = data;
   if (!m)
@@ -478,7 +480,7 @@ static int pop_fetch_headers(struct Mailbox *m)
    * the availability of our cache */
   const bool c_message_cache_clean = cs_subset_bool(NeoMutt->sub, "message_cache_clean");
   if (c_message_cache_clean)
-    mutt_bcache_list(adata->bcache, msg_cache_check, m);
+    mutt_bcache_list(adata->bcache, pop_bcache_delete, m);
 
   mutt_clear_error();
   return new_count - old_count;
diff --git a/pop/private.h b/pop/private.h
index 77ae2ea3d..153454e21 100644
--- a/pop/private.h
+++ b/pop/private.h
@@ -77,6 +77,8 @@ struct PopCache
 struct PopAuth
 {
   /**
+   * @defgroup pop_authenticate POP Authenticaion API
+   *
    * authenticate - Authenticate a POP connection
    * @param adata  POP Account data
    * @param method Name of this authentication method (UNUSED)
diff --git a/postpone/dlg_postpone.c b/postpone/dlg_postpone.c
index 49d4126b9..5a9a758c4 100644
--- a/postpone/dlg_postpone.c
+++ b/postpone/dlg_postpone.c
@@ -97,7 +97,9 @@ static const struct Mapping PostponedHelp[] = {
 };
 
 /**
- * post_make_entry - Format a menu item for the email list - Implements Menu::make_entry() - @ingroup menu_make_entry
+ * post_make_entry - Format an Email for the Menu - Implements Menu::make_entry() - @ingroup menu_make_entry
+ *
+ * @sa $index_format, index_format_str()
  */
 static void post_make_entry(struct Menu *menu, char *buf, size_t buflen, int line)
 {
diff --git a/rfc3676.c b/rfc3676.c
index 1c7f16335..679a92b7d 100644
--- a/rfc3676.c
+++ b/rfc3676.c
@@ -314,7 +314,7 @@ static void print_fixed_line(const char *line, struct State *state, int ql,
 }
 
 /**
- * rfc3676_handler - Body handler implementing RFC3676 for format=flowed - Implements ::handler_t - @ingroup handler_api
+ * rfc3676_handler - Handler for format=flowed - Implements ::handler_t - @ingroup handler_api
  * @retval 0 Always
  */
 int rfc3676_handler(struct Body *a, struct State *state)
diff --git a/send/smtp.c b/send/smtp.c
index 7240dbda5..bfcfec2a0 100644
--- a/send/smtp.c
+++ b/send/smtp.c
@@ -312,7 +312,7 @@ done:
 }
 
 /**
- * smtp_get_field - Get connection login credentials - Implements ConnAccount::get_field()
+ * smtp_get_field - Get connection login credentials - Implements ConnAccount::get_field() - @ingroup conn_account_get_field
  */
 static const char *smtp_get_field(enum ConnAccountField field, void *gf_data)
 {
diff --git a/sort.c b/sort.c
index deca1da2d..b69ca24b7 100644
--- a/sort.c
+++ b/sort.c
@@ -437,4 +437,6 @@ void mutt_sort_headers(struct MailboxView *mv, bool init)
 
   if (m->verbose)
     mutt_clear_error();
+
+  return;
 }
diff --git a/store/bdb.c b/store/bdb.c
index 91aaa84ce..5e2665514 100644
--- a/store/bdb.c
+++ b/store/bdb.c
@@ -111,7 +111,7 @@ static void dbt_empty_init(DBT *dbt)
 }
 
 /**
- * store_bdb_open - Implements StoreOps::open() - @ingroup store_open
+ * store_bdb_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_bdb_open(const char *path)
 {
@@ -178,7 +178,7 @@ fail_close:
 }
 
 /**
- * store_bdb_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_bdb_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_bdb_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -202,7 +202,7 @@ static void *store_bdb_fetch(StoreHandle *store, const char *key, size_t klen, s
 }
 
 /**
- * store_bdb_free - Implements StoreOps::free() - @ingroup store_free
+ * store_bdb_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_bdb_free(StoreHandle *store, void **ptr)
 {
@@ -210,7 +210,7 @@ static void store_bdb_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_bdb_store - Implements StoreOps::store() - @ingroup store_store
+ * store_bdb_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_bdb_store(StoreHandle *store, const char *key, size_t klen,
                            void *value, size_t vlen)
@@ -235,7 +235,7 @@ static int store_bdb_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_bdb_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_bdb_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_bdb_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -251,7 +251,7 @@ static int store_bdb_delete_record(StoreHandle *store, const char *key, size_t k
 }
 
 /**
- * store_bdb_close - Implements StoreOps::close() - @ingroup store_close
+ * store_bdb_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_bdb_close(StoreHandle **ptr)
 {
@@ -271,7 +271,7 @@ static void store_bdb_close(StoreHandle **ptr)
 }
 
 /**
- * store_bdb_version - Implements StoreOps::version() - @ingroup store_version
+ * store_bdb_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_bdb_version(void)
 {
diff --git a/store/gdbm.c b/store/gdbm.c
index 9e89db354..0c14804ec 100644
--- a/store/gdbm.c
+++ b/store/gdbm.c
@@ -38,7 +38,7 @@
 #include "lib.h"
 
 /**
- * store_gdbm_open - Implements StoreOps::open() - @ingroup store_open
+ * store_gdbm_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_gdbm_open(const char *path)
 {
@@ -59,7 +59,7 @@ static StoreHandle *store_gdbm_open(const char *path)
 }
 
 /**
- * store_gdbm_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_gdbm_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_gdbm_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -81,7 +81,7 @@ static void *store_gdbm_fetch(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_gdbm_free - Implements StoreOps::free() - @ingroup store_free
+ * store_gdbm_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_gdbm_free(StoreHandle *store, void **ptr)
 {
@@ -89,7 +89,7 @@ static void store_gdbm_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_gdbm_store - Implements StoreOps::store() - @ingroup store_store
+ * store_gdbm_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_gdbm_store(StoreHandle *store, const char *key, size_t klen,
                             void *value, size_t vlen)
@@ -113,7 +113,7 @@ static int store_gdbm_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_gdbm_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_gdbm_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_gdbm_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -132,7 +132,7 @@ static int store_gdbm_delete_record(StoreHandle *store, const char *key, size_t
 }
 
 /**
- * store_gdbm_close - Implements StoreOps::close() - @ingroup store_close
+ * store_gdbm_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_gdbm_close(StoreHandle **ptr)
 {
@@ -146,7 +146,7 @@ static void store_gdbm_close(StoreHandle **ptr)
 }
 
 /**
- * store_gdbm_version - Implements StoreOps::version() - @ingroup store_version
+ * store_gdbm_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_gdbm_version(void)
 {
diff --git a/store/kc.c b/store/kc.c
index a3d3892f0..90169f1a8 100644
--- a/store/kc.c
+++ b/store/kc.c
@@ -37,7 +37,7 @@
 #include "lib.h"
 
 /**
- * store_kyotocabinet_open - Implements StoreOps::open() - @ingroup store_open
+ * store_kyotocabinet_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_kyotocabinet_open(const char *path)
 {
@@ -67,7 +67,7 @@ static StoreHandle *store_kyotocabinet_open(const char *path)
 }
 
 /**
- * store_kyotocabinet_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_kyotocabinet_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_kyotocabinet_fetch(StoreHandle *store, const char *key,
                                       size_t klen, size_t *vlen)
@@ -81,7 +81,7 @@ static void *store_kyotocabinet_fetch(StoreHandle *store, const char *key,
 }
 
 /**
- * store_kyotocabinet_free - Implements StoreOps::free() - @ingroup store_free
+ * store_kyotocabinet_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_kyotocabinet_free(StoreHandle *store, void **ptr)
 {
@@ -93,7 +93,7 @@ static void store_kyotocabinet_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_kyotocabinet_store - Implements StoreOps::store() - @ingroup store_store
+ * store_kyotocabinet_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_kyotocabinet_store(StoreHandle *store, const char *key,
                                     size_t klen, void *value, size_t vlen)
@@ -112,7 +112,7 @@ static int store_kyotocabinet_store(StoreHandle *store, const char *key,
 }
 
 /**
- * store_kyotocabinet_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_kyotocabinet_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_kyotocabinet_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -130,7 +130,7 @@ static int store_kyotocabinet_delete_record(StoreHandle *store, const char *key,
 }
 
 /**
- * store_kyotocabinet_close - Implements StoreOps::close() - @ingroup store_close
+ * store_kyotocabinet_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_kyotocabinet_close(StoreHandle **ptr)
 {
@@ -149,7 +149,7 @@ static void store_kyotocabinet_close(StoreHandle **ptr)
 }
 
 /**
- * store_kyotocabinet_version - Implements StoreOps::version() - @ingroup store_version
+ * store_kyotocabinet_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_kyotocabinet_version(void)
 {
diff --git a/store/lmdb.c b/store/lmdb.c
index 90c696ece..1625e1746 100644
--- a/store/lmdb.c
+++ b/store/lmdb.c
@@ -144,7 +144,7 @@ static int lmdb_get_write_txn(struct LmdbStoreData *sdata)
 }
 
 /**
- * store_lmdb_open - Implements StoreOps::open() - @ingroup store_open
+ * store_lmdb_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_lmdb_open(const char *path)
 {
@@ -201,7 +201,7 @@ fail_env:
 }
 
 /**
- * store_lmdb_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_lmdb_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_lmdb_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -241,7 +241,7 @@ static void *store_lmdb_fetch(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_lmdb_free - Implements StoreOps::free() - @ingroup store_free
+ * store_lmdb_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_lmdb_free(StoreHandle *store, void **ptr)
 {
@@ -249,7 +249,7 @@ static void store_lmdb_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_lmdb_store - Implements StoreOps::store() - @ingroup store_store
+ * store_lmdb_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_lmdb_store(StoreHandle *store, const char *key, size_t klen,
                             void *value, size_t vlen)
@@ -285,7 +285,7 @@ static int store_lmdb_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_lmdb_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_lmdb_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_lmdb_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -318,7 +318,7 @@ static int store_lmdb_delete_record(StoreHandle *store, const char *key, size_t
 }
 
 /**
- * store_lmdb_close - Implements StoreOps::close() - @ingroup store_close
+ * store_lmdb_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_lmdb_close(StoreHandle **ptr)
 {
@@ -344,7 +344,7 @@ static void store_lmdb_close(StoreHandle **ptr)
 }
 
 /**
- * store_lmdb_version - Implements StoreOps::version() - @ingroup store_version
+ * store_lmdb_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_lmdb_version(void)
 {
diff --git a/store/qdbm.c b/store/qdbm.c
index e64a4ce25..3ac90f14a 100644
--- a/store/qdbm.c
+++ b/store/qdbm.c
@@ -39,7 +39,7 @@
 #include "lib.h"
 
 /**
- * store_qdbm_open - Implements StoreOps::open() - @ingroup store_open
+ * store_qdbm_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_qdbm_open(const char *path)
 {
@@ -53,7 +53,7 @@ static StoreHandle *store_qdbm_open(const char *path)
 }
 
 /**
- * store_qdbm_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_qdbm_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_qdbm_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -69,7 +69,7 @@ static void *store_qdbm_fetch(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_qdbm_free - Implements StoreOps::free() - @ingroup store_free
+ * store_qdbm_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_qdbm_free(StoreHandle *store, void **ptr)
 {
@@ -77,7 +77,7 @@ static void store_qdbm_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_qdbm_store - Implements StoreOps::store() - @ingroup store_store
+ * store_qdbm_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_qdbm_store(StoreHandle *store, const char *key, size_t klen,
                             void *value, size_t vlen)
@@ -94,7 +94,7 @@ static int store_qdbm_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_qdbm_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_qdbm_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_qdbm_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -110,7 +110,7 @@ static int store_qdbm_delete_record(StoreHandle *store, const char *key, size_t
 }
 
 /**
- * store_qdbm_close - Implements StoreOps::close() - @ingroup store_close
+ * store_qdbm_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_qdbm_close(StoreHandle **ptr)
 {
@@ -124,7 +124,7 @@ static void store_qdbm_close(StoreHandle **ptr)
 }
 
 /**
- * store_qdbm_version - Implements StoreOps::version() - @ingroup store_version
+ * store_qdbm_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_qdbm_version(void)
 {
diff --git a/store/rocksdb.c b/store/rocksdb.c
index 8a46c3178..836e0635a 100644
--- a/store/rocksdb.c
+++ b/store/rocksdb.c
@@ -70,7 +70,7 @@ static struct RocksDbStoreData *rocksdb_sdata_new(void)
 }
 
 /**
- * store_rocksdb_open - Implements StoreOps::open() - @ingroup store_open
+ * store_rocksdb_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_rocksdb_open(const char *path)
 {
@@ -112,7 +112,7 @@ static StoreHandle *store_rocksdb_open(const char *path)
 }
 
 /**
- * store_rocksdb_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_rocksdb_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_rocksdb_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -134,7 +134,7 @@ static void *store_rocksdb_fetch(StoreHandle *store, const char *key, size_t kle
 }
 
 /**
- * store_rocksdb_free - Implements StoreOps::free() - @ingroup store_free
+ * store_rocksdb_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_rocksdb_free(StoreHandle *store, void **ptr)
 {
@@ -142,7 +142,7 @@ static void store_rocksdb_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_rocksdb_store - Implements StoreOps::store() - @ingroup store_store
+ * store_rocksdb_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_rocksdb_store(StoreHandle *store, const char *key, size_t klen,
                                void *value, size_t vlen)
@@ -165,7 +165,7 @@ static int store_rocksdb_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_rocksdb_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_rocksdb_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_rocksdb_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -187,7 +187,7 @@ static int store_rocksdb_delete_record(StoreHandle *store, const char *key, size
 }
 
 /**
- * store_rocksdb_close - Implements StoreOps::close() - @ingroup store_close
+ * store_rocksdb_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_rocksdb_close(StoreHandle **ptr)
 {
@@ -207,7 +207,7 @@ static void store_rocksdb_close(StoreHandle **ptr)
 }
 
 /**
- * store_rocksdb_version - Implements StoreOps::version() - @ingroup store_version
+ * store_rocksdb_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_rocksdb_version(void)
 {
diff --git a/store/tc.c b/store/tc.c
index 10e48dd01..4fcc40032 100644
--- a/store/tc.c
+++ b/store/tc.c
@@ -38,7 +38,7 @@
 #include "lib.h"
 
 /**
- * store_tokyocabinet_open - Implements StoreOps::open() - @ingroup store_open
+ * store_tokyocabinet_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_tokyocabinet_open(const char *path)
 {
@@ -62,7 +62,7 @@ static StoreHandle *store_tokyocabinet_open(const char *path)
 }
 
 /**
- * store_tokyocabinet_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_tokyocabinet_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_tokyocabinet_fetch(StoreHandle *store, const char *key,
                                       size_t klen, size_t *vlen)
@@ -79,7 +79,7 @@ static void *store_tokyocabinet_fetch(StoreHandle *store, const char *key,
 }
 
 /**
- * store_tokyocabinet_free - Implements StoreOps::free() - @ingroup store_free
+ * store_tokyocabinet_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_tokyocabinet_free(StoreHandle *store, void **ptr)
 {
@@ -87,7 +87,7 @@ static void store_tokyocabinet_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_tokyocabinet_store - Implements StoreOps::store() - @ingroup store_store
+ * store_tokyocabinet_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_tokyocabinet_store(StoreHandle *store, const char *key,
                                     size_t klen, void *value, size_t vlen)
@@ -106,7 +106,7 @@ static int store_tokyocabinet_store(StoreHandle *store, const char *key,
 }
 
 /**
- * store_tokyocabinet_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_tokyocabinet_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_tokyocabinet_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -124,7 +124,7 @@ static int store_tokyocabinet_delete_record(StoreHandle *store, const char *key,
 }
 
 /**
- * store_tokyocabinet_close - Implements StoreOps::close() - @ingroup store_close
+ * store_tokyocabinet_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_tokyocabinet_close(StoreHandle **ptr)
 {
@@ -143,7 +143,7 @@ static void store_tokyocabinet_close(StoreHandle **ptr)
 }
 
 /**
- * store_tokyocabinet_version - Implements StoreOps::version() - @ingroup store_version
+ * store_tokyocabinet_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_tokyocabinet_version(void)
 {
diff --git a/store/tdb.c b/store/tdb.c
index 26b62dd43..a0cd115a3 100644
--- a/store/tdb.c
+++ b/store/tdb.c
@@ -35,7 +35,7 @@
 #include "lib.h"
 
 /**
- * store_tdb_open - Implements StoreOps::open() - @ingroup store_open
+ * store_tdb_open - Open a connection to a Store - Implements StoreOps::open() - @ingroup store_open
  */
 static StoreHandle *store_tdb_open(const char *path)
 {
@@ -56,7 +56,7 @@ static StoreHandle *store_tdb_open(const char *path)
 }
 
 /**
- * store_tdb_fetch - Implements StoreOps::fetch() - @ingroup store_fetch
+ * store_tdb_fetch - Fetch a Value from the Store - Implements StoreOps::fetch() - @ingroup store_fetch
  */
 static void *store_tdb_fetch(StoreHandle *store, const char *key, size_t klen, size_t *vlen)
 {
@@ -77,7 +77,7 @@ static void *store_tdb_fetch(StoreHandle *store, const char *key, size_t klen, s
 }
 
 /**
- * store_tdb_free - Implements StoreOps::free() - @ingroup store_free
+ * store_tdb_free - Free a Value returned by fetch() - Implements StoreOps::free() - @ingroup store_free
  */
 static void store_tdb_free(StoreHandle *store, void **ptr)
 {
@@ -85,7 +85,7 @@ static void store_tdb_free(StoreHandle *store, void **ptr)
 }
 
 /**
- * store_tdb_store - Implements StoreOps::store() - @ingroup store_store
+ * store_tdb_store - Write a Value to the Store - Implements StoreOps::store() - @ingroup store_store
  */
 static int store_tdb_store(StoreHandle *store, const char *key, size_t klen,
                            void *value, size_t vlen)
@@ -108,7 +108,7 @@ static int store_tdb_store(StoreHandle *store, const char *key, size_t klen,
 }
 
 /**
- * store_tdb_delete_record - Implements StoreOps::delete_record() - @ingroup store_delete_record
+ * store_tdb_delete_record - Delete a record from the Store - Implements StoreOps::delete_record() - @ingroup store_delete_record
  */
 static int store_tdb_delete_record(StoreHandle *store, const char *key, size_t klen)
 {
@@ -126,7 +126,7 @@ static int store_tdb_delete_record(StoreHandle *store, const char *key, size_t k
 }
 
 /**
- * store_tdb_close - Implements StoreOps::close() - @ingroup store_close
+ * store_tdb_close - Close a Store connection - Implements StoreOps::close() - @ingroup store_close
  */
 static void store_tdb_close(StoreHandle **ptr)
 {
@@ -140,7 +140,7 @@ static void store_tdb_close(StoreHandle **ptr)
 }
 
 /**
- * store_tdb_version - Implements StoreOps::version() - @ingroup store_version
+ * store_tdb_version - Get a Store version string - Implements StoreOps::version() - @ingroup store_version
  */
 static const char *store_tdb_version(void)
 {