diff --git a/src/Magnum/Audio/AbstractImporter.h b/src/Magnum/Audio/AbstractImporter.h
index bbcc83bfe..73cdc6586 100644
--- a/src/Magnum/Audio/AbstractImporter.h
+++ b/src/Magnum/Audio/AbstractImporter.h
@@ -167,7 +167,8 @@ class MAGNUM_AUDIO_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * Closes previous file, if it was opened, and tries to open given
          * file. Available only if @ref ImporterFeature::OpenData is supported.
-         * Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref openFile()
          */
         bool openData(Containers::ArrayView<const void> data);
@@ -176,7 +177,8 @@ class MAGNUM_AUDIO_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Open file
          *
          * Closes previous file, if it was opened, and tries to open given
-         * file. Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * file. On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref openData()
          */
         bool openFile(const std::string& filename);
diff --git a/src/Magnum/ShaderTools/AbstractConverter.h b/src/Magnum/ShaderTools/AbstractConverter.h
index f3fbcdf04..e284a9e7d 100644
--- a/src/Magnum/ShaderTools/AbstractConverter.h
+++ b/src/Magnum/ShaderTools/AbstractConverter.h
@@ -754,7 +754,7 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * -    @cpp false @ce if validation doesn't pass. If an external error
          *      occurs (for example a referenced file not being found), it may
          *      also happen that the returned string is empty and a message is
-         *      printed to error output instead.
+         *      printed to @relativeref{Magnum,Error} instead.
          *
          * @see @ref features(), @ref validateFile()
          */
@@ -773,7 +773,7 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * -    @cpp false @ce if validation doesn't pass. If an external error
          *      occurs (for example when a file cannot be read), it may also
          *      happen that the returned string is empty and a message is
-         *      printed to error output instead.
+         *      printed to @relativeref{Magnum,Error} instead.
          *
          * Corresponds to the `--validate` option in
          * @ref magnum-shaderconverter "magnum-shaderconverter".
@@ -785,8 +785,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Convert shader data to a data
          *
          * Available only if @ref ConverterFeature::ConvertData is supported.
-         * On failure the function prints an error message and returns
-         * @cpp nullptr @ce.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertDataToFile(),
          *      @ref convertFileToData(), @ref convertFileToFile()
          */
@@ -796,8 +796,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Convert shader data to a file
          *
          * Available only if @ref ConverterFeature::ConvertData is supported.
-         * Returns @cpp true @ce on success, prints an error message and
-         * returns @cpp false @ce otherwise.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref convertDataToData(),
          *      @ref convertFileToData(), @ref convertFileToFile()
          */
@@ -807,9 +807,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Convert shader file to a file
          *
          * Available only if @ref ConverterFeature::ConvertFile or
-         * @ref ConverterFeature::ConvertData is supported. Returns
-         * @cpp true @ce on success, prints an error message and returns
-         * @cpp false @ce otherwise.
+         * @ref ConverterFeature::ConvertData is supported. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp false @ce.
          *
          * Corresponds to the default behavior of
          * @ref magnum-shaderconverter "magnum-shaderconverter" when neither
@@ -823,8 +822,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Convert shader data to a file
          *
          * Available only if @ref ConverterFeature::ConvertData is supported.
-         * On failure the function prints an error message and returns
-         * @cpp nullptr @ce.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertFileToFile(),
          *      @ref convertDataToFile(), @ref convertDataToData()
          */
@@ -834,7 +833,7 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Link shader data together to a data
          *
          * Available only if @ref ConverterFeature::LinkData is supported. On
-         * failure the function prints an error message and returns
+         * failure prints a message to @relativeref{Magnum,Error} and returns
          * @cpp nullptr @ce. Can't be called if
          * @ref ConverterFlag::PreprocessOnly is set --- in that case
          * @ref convertDataToData() has to be used instead.
@@ -849,8 +848,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Link shader data together to a file
          *
          * Available only if @ref ConverterFeature::LinkData is supported. On
-         * Returns @cpp true @ce on success, prints an error message and
-         * returns @cpp false @ce otherwise. Can't be called if
+         * failure prints a message to @relativeref{Magnum,Error} and returns
+         * @cpp false @ce. Can't be called if
          * @ref ConverterFlag::PreprocessOnly is set --- in that case
          * @ref convertDataToFile() has to be used instead.
          * @see @ref features(), @ref linkFilesToFile(),
@@ -865,11 +864,10 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
          * @brief Link shader files together to a file
          *
          * Available only if @ref ConverterFeature::LinkFile or
-         * @ref ConverterFeature::LinkData is supported. Returns @cpp true @ce
-         * on success, prints an error message and returns @cpp false @ce
-         * otherwise. Can't be called if @ref ConverterFlag::PreprocessOnly is
-         * set --- in that case  @ref convertFileToFile() has to be used
-         * instead.
+         * @ref ConverterFeature::LinkData is supported. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp false @ce.
+         * Can't be called if @ref ConverterFlag::PreprocessOnly is set --- in
+         * that case @ref convertFileToFile() has to be used instead.
          *
          * Corresponds to the `--link` option in
          * @ref magnum-shaderconverter "magnum-shaderconverter".
@@ -884,8 +882,8 @@ class MAGNUM_SHADERTOOLS_EXPORT AbstractConverter: public PluginManager::Abstrac
         /**
          * @brief Link shader files together to a data
          *
-         * Available only if @ref ConverterFeature::LinkData is supported, On
-         * failure the function prints an error message and returns
+         * Available only if @ref ConverterFeature::LinkData is supported. On
+         * failure prints a message to @relativeref{Magnum,Error} and returns
          * @cpp nullptr @ce. Can't be called if
          * @ref ConverterFlag::PreprocessOnly is set --- in that case
          * @ref convertFileToData() has to be used instead.
diff --git a/src/Magnum/Text/AbstractFont.h b/src/Magnum/Text/AbstractFont.h
index d79fa07a8..376d1b0b1 100644
--- a/src/Magnum/Text/AbstractFont.h
+++ b/src/Magnum/Text/AbstractFont.h
@@ -318,7 +318,8 @@ class MAGNUM_TEXT_EXPORT AbstractFont: public PluginManager::AbstractPlugin {
          *
          * Closes previous file, if it was opened, and tries to open given
          * file. Available only if @ref FontFeature::OpenData is supported.
-         * Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref openFile()
          */
         bool openData(Containers::ArrayView<const void> data, Float size);
@@ -343,7 +344,8 @@ class MAGNUM_TEXT_EXPORT AbstractFont: public PluginManager::AbstractPlugin {
          * @param size          Font size
          *
          * Closes previous file, if it was opened, and tries to open given
-         * file. Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * file. On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          */
         bool openFile(const std::string& filename, Float size);
 
diff --git a/src/Magnum/Text/AbstractFontConverter.h b/src/Magnum/Text/AbstractFontConverter.h
index d1d487061..d27b52b59 100644
--- a/src/Magnum/Text/AbstractFontConverter.h
+++ b/src/Magnum/Text/AbstractFontConverter.h
@@ -218,11 +218,12 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          *
          * Available only if @ref FontConverterFeature::ConvertData and
          * @ref FontConverterFeature::ExportFont is supported. Returns pairs of
-         * filename and data on success, empty vector otherwise. All data will
-         * be sharing common basename derived from @p filename. If the plugin
-         * doesn't have @ref FontConverterFeature::MultiFile, only one pair is
-         * returned, thus using @ref exportFontToSingleData() might be more
-         * convenient in that case.
+         * filename and data on success, prints a message to
+         * @relativeref{Magnum,Error} and returns an empty vector otherwise.
+         * All data will be sharing common basename derived from @p filename.
+         * If the plugin doesn't have @ref FontConverterFeature::MultiFile,
+         * only one pair is returned, thus using @ref exportFontToSingleData()
+         * might be more convenient in that case.
          * @see @ref features(), @ref exportFontToFile(),
          *      @ref exportGlyphCacheToData()
          */
@@ -233,9 +234,9 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          *
          * Available only if @ref FontConverterFeature::ConvertData and
          * @ref FontConverterFeature::ExportFont is supported and the plugin
-         * doesn't have @ref FontConverterFeature::MultiFile. Returns data on
-         * success, zero-sized array otherwise. See @ref exportFontToData() for
-         * more information.
+         * doesn't have @ref FontConverterFeature::MultiFile. On failure prints
+         * a message to @relativeref{Magnum,Error} and returns
+         * @cpp nullptr @ce. See @ref exportFontToData() for more information.
          * @see @ref features(), @ref exportFontToFile(),
          *      @ref exportGlyphCacheToSingleData()
          */
@@ -247,9 +248,9 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          * Available only if @ref FontConverterFeature::ExportFont is
          * supported. If the plugin has @ref FontConverterFeature::MultiFile,
          * the function will create more than one file in given path, all
-         * sharing common basename derived from @p filename. Returns
-         * @cpp true @ce on success, @cpp false @ce otherwise. See
-         * @ref exportFontToData() for more information.
+         * sharing common basename derived from @p filename. On failure prints
+         * a message to @relativeref{Magnum,Error} and returns @cpp false @ce.
+         * See @ref exportFontToData() for more information.
          * @see @ref features(), @ref exportFontToData(),
          *      @ref exportGlyphCacheToFile()
          */
@@ -262,11 +263,13 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          *
          * Available only if @ref FontConverterFeature::ConvertData and
          * @ref FontConverterFeature::ExportGlyphCache is supported. Returns
-         * pairs of filename and data on success, empty vector otherwise. All
-         * data will be sharing common basename derived from @p filename. If
-         * the plugin doesn't have @ref FontConverterFeature::MultiFile, only
-         * one pair is returned, thus using @ref exportGlyphCacheToSingleData()
-         * might be more convenient in that case.
+         * pairs of filename and data on success, prints a message to
+         * @relativeref{Magnum,Error} and returns an empty vector otherwise.
+         * All data will be sharing common basename derived from @p filename.
+         * If the plugin doesn't have @ref FontConverterFeature::MultiFile,
+         * only one pair is returned, thus using
+         * @ref exportGlyphCacheToSingleData() might be more convenient in that
+         * case.
          *
          * All glyphs from given cache will be exported. If you want to export
          * smaller subset, fill the cache with less characters.
@@ -280,9 +283,10 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          *
          * Available only if @ref FontConverterFeature::ConvertData and
          * @ref FontConverterFeature::ExportGlyphCache is supported and the
-         * plugin doesn't have @ref FontConverterFeature::MultiFile. Returns
-         * data on success, zero-sized array otherwise. See
-         * @ref exportGlyphCacheToData() for more information.
+         * plugin doesn't have @ref FontConverterFeature::MultiFile. On failure
+         * prints a message to @relativeref{Magnum,Error} and returns
+         * @cpp nullptr @ce. See @ref exportGlyphCacheToData() for more
+         * information.
          * @see @ref features(), @ref exportGlyphCacheToFile(),
          *      @ref importGlyphCacheFromSingleData()
          */
@@ -294,8 +298,8 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          * Available only if @ref FontConverterFeature::ExportGlyphCache is
          * supported. If the plugin has @ref FontConverterFeature::MultiFile,
          * the function will create more than one file in given path, all
-         * sharing common basename derived from @p filename. Returns
-         * @cpp true @ce on success, @cpp false @ce otherwise.
+         * sharing common basename derived from @p filename. On failure prints
+         * a message to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref exportGlyphCacheToData(),
          *      @ref exportFontToFile()
          */
@@ -306,11 +310,12 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          * @param data      Pairs of filename and file data
          *
          * Available only if @ref FontConverterFeature::ConvertData and
-         * @ref FontConverterFeature::ImportGlyphCache is supported. Returns
-         * imported cache on success, @cpp nullptr @ce otherwise. If the plugin
-         * doesn't have @ref FontConverterFeature::MultiFile, only one file is
-         * needed, thus using @ref importGlyphCacheFromSingleData() might be
-         * more convenient in that case.
+         * @ref FontConverterFeature::ImportGlyphCache is supported. On failure
+         * prints a message to @relativeref{Magnum,Error} and returns
+         * @cpp nullptr @ce. If the plugin doesn't have
+         * @ref FontConverterFeature::MultiFile, only one file is needed, thus
+         * using @ref importGlyphCacheFromSingleData() might be more convenient
+         * in that case.
          * @see @ref features(), @ref importGlyphCacheFromFile(),
          *      @ref exportGlyphCacheToData()
          */
@@ -321,9 +326,10 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          *
          * Available only if @ref FontConverterFeature::ConvertData and
          * @ref FontConverterFeature::ImportGlyphCache is supported and the
-         * plugin doesn't have @ref FontConverterFeature::MultiFile. Returns
-         * imported cache on success, @cpp nullptr @ce otherwise. See
-         * @ref importGlyphCacheFromData() for multi-file conversion.
+         * plugin doesn't have @ref FontConverterFeature::MultiFile. On failure
+         * prints a message to @relativeref{Magnum,Error} and returns
+         * @cpp nullptr @ce. See @ref importGlyphCacheFromData() for multi-file
+         * conversion.
          * @see @ref features(), @ref importGlyphCacheFromFile(),
          *      @ref exportFontToSingleData()
          */
@@ -335,8 +341,8 @@ class MAGNUM_TEXT_EXPORT AbstractFontConverter: public PluginManager::AbstractPl
          * Available only if @ref FontConverterFeature::ImportGlyphCache is
          * supported. If the plugin has @ref FontConverterFeature::MultiFile,
          * the function will use additional files in given path, all sharing
-         * common basename derived from @p filename. Returns imported cache on
-         * success, @cpp nullptr @ce otherwise.
+         * common basename derived from @p filename. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref importGlyphCacheFromData(),
          *      @ref exportGlyphCacheToFile()
          */
diff --git a/src/Magnum/Trade/AbstractImageConverter.h b/src/Magnum/Trade/AbstractImageConverter.h
index 728b87618..8066b08fa 100644
--- a/src/Magnum/Trade/AbstractImageConverter.h
+++ b/src/Magnum/Trade/AbstractImageConverter.h
@@ -707,10 +707,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::Convert1D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const CompressedImageView1D&),
          *      @ref convert(const ImageData1D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -722,10 +722,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::Convert2D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const CompressedImageView2D&),
          *      @ref convert(const ImageData2D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -753,10 +753,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::Convert3D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const CompressedImageView3D&),
          *      @ref convert(const ImageData3D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -768,10 +768,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::ConvertCompressed1D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const ImageView1D&),
          *      @ref convert(const ImageData1D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -783,10 +783,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::ConvertCompressed2D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const ImageView2D&),
          *      @ref convert(const ImageData2D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -798,10 +798,10 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref ImageConverterFeature::ConvertCompressed3D is
-         * supported. Returns converted image on success,
-         * @ref Containers::NullOpt otherwise. The implementation is allowed to
-         * return both a compressed an an uncompressed image, see documentation
-         * of a particular converter for more information.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt. The implementation is allowed
+         * to return both a compressed an an uncompressed image, see
+         * documentation of a particular converter for more information.
          * @see @ref features(), @ref convert(const ImageView3D&),
          *      @ref convert(const ImageData3D&), @ref convertToData(),
          *      @ref convertToFile(), @ref ImageData::isCompressed()
@@ -863,7 +863,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::Convert1DToData or
          * @ref ImageConverterFeature::ConvertLevels1DToData is supported. The
          * image view is expected to not be @cpp nullptr @ce and to have a
-         * non-zero size. Returns data on success, @cpp nullptr @ce otherwise.
+         * non-zero size. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const CompressedImageView1D&),
          *      @ref convertToData(const ImageData1D&), @ref convert(),
          *      @ref convertToFile()
@@ -877,8 +878,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::Convert2DToData or
          * @ref ImageConverterFeature::ConvertLevels2DToData is supported. The
          * image view is expected to not be @cpp nullptr @ce and to have a
-         * non-zero size in all dimensions. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * non-zero size in all dimensions. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const CompressedImageView2D&),
          *      @ref convertToData(const ImageData2D&), @ref convert(),
          *      @ref convertToFile()
@@ -901,8 +902,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::Convert3DToData or
          * @ref ImageConverterFeature::ConvertLevels3DToData is supported. The
          * image view is expected to not be @cpp nullptr @ce and to have a
-         * non-zero size in all dimensions. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * non-zero size in all dimensions. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const CompressedImageView3D&),
          *      @ref convertToData(const ImageData3D&), @ref convert(),
          *      @ref convertToFile()
@@ -916,8 +917,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed1DToData
          * or @ref ImageConverterFeature::ConvertCompressedLevels1DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size. Returns data on success, @cpp nullptr @ce
-         * otherwise.
+         * to have a non-zero size. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const ImageView1D&),
          *      @ref convertToData(const ImageData1D&), @ref convert(),
          *      @ref convertToFile()
@@ -931,8 +932,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed2DToData
          * or @ref ImageConverterFeature::ConvertCompressedLevels2DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size in all dimensions. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * to have a non-zero size in all dimensions. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const ImageView2D&),
          *      @ref convertToData(const ImageData2D&), @ref convert(),
          *      @ref convertToFile()
@@ -955,8 +956,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed3DToData
          * or @ref ImageConverterFeature::ConvertCompressedLevels3DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size in all dimensions. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * to have a non-zero size in all dimensions. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(const ImageView3D&),
          *      @ref convertToData(const ImageData3D&), @ref convert(),
          *      @ref convertToFile()
@@ -1018,8 +1019,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size, and all of them sharing the same pixel format. Note
          * that certain converters may impose additional size and order
          * restrictions on the images, see documentation of a particular plugin
-         * for more information. Returns data on success, @cpp nullptr @ce
-         * otherwise.
+         * for more information. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const CompressedImageView1D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1037,8 +1038,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const CompressedImageView2D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1056,8 +1057,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const CompressedImageView3D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1075,8 +1076,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size, and all views sharing the same pixel format. Note
          * that certain converters may impose additional size and order
          * restrictions on the images, see documentation of a particular plugin
-         * for more information. Returns data on success, @cpp nullptr @ce
-         * otherwise.
+         * for more information. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const ImageView1D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1094,8 +1095,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const ImageView2D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1113,8 +1114,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns data on success,
-         * @cpp nullptr @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp nullptr @ce.
          * @see @ref features(), @ref convertToData(Containers::ArrayView<const ImageView3D>),
          *      @ref convert(), @ref convertToFile()
          */
@@ -1129,7 +1130,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::Convert1DToFile or
          * @ref ImageConverterFeature::Convert1DToData is supported. The image
          * view is expected to not be @cpp nullptr @ce and to have a non-zero
-         * size. Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * size. On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(const CompressedImageView1D&, Containers::StringView),
          *      @ref convertToFile(const ImageData1D&, Containers::StringView),
          *      @ref convert(), @ref convertToData()
@@ -1168,7 +1170,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::Convert3DToFile or
          * @ref ImageConverterFeature::Convert3DToData is supported. The image
          * view is expected to not be @cpp nullptr @ce and to have a non-zero
-         * size. Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * size. On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(const CompressedImageView3D&, Containers::StringView),
          *      @ref convertToFile(const ImageData3D&, Containers::StringView),
          *      @ref convert(), @ref convertToData()
@@ -1182,8 +1185,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed1DToFile
          * or @ref ImageConverterFeature::ConvertCompressed1DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size in all dimensions. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * to have a non-zero size in all dimensions. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(const ImageView1D&, Containers::StringView),
          *      @ref convertToFile(const ImageData1D&, Containers::StringView),
          *      @ref convert(), @ref convertToData()
@@ -1197,8 +1200,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed2DToFile
          * or @ref ImageConverterFeature::ConvertCompressed2DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size in all dimensions. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * to have a non-zero size in all dimensions. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(const ImageView2D&, Containers::StringView),
          *      @ref convertToFile(const ImageData2D&, Containers::StringView),
          *      @ref convert(), @ref convertToData()
@@ -1222,8 +1225,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * Available only if @ref ImageConverterFeature::ConvertCompressed3DToFile
          * or @ref ImageConverterFeature::ConvertCompressed3DToData is
          * supported. The image view is expected to not be @cpp nullptr @ce and
-         * to have a non-zero size in all dimensions. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * to have a non-zero size in all dimensions. On failure prints a
+         * message to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(const ImageView3D&, Containers::StringView),
          *      @ref convertToFile(const ImageData3D&, Containers::StringView),
          *      @ref convert(), @ref convertToData()
@@ -1298,8 +1301,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size, and all views sharing the same pixel format. Note
          * that certain converters may impose additional size and order
          * restrictions on the images, see documentation of a particular plugin
-         * for more information. Returns @cpp true @ce on success,
-         * @cpp false @ce otherwise.
+         * for more information. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const CompressedImageView1D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
@@ -1317,8 +1320,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const CompressedImageView2D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
@@ -1336,8 +1339,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const CompressedImageView3D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
@@ -1355,8 +1358,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size, and all views sharing the same pixel format. Note
          * that certain converters may impose additional size and order
          * restrictions on the images, see documentation of a particular plugin
-         * for more information. Returns @cpp true @ce on success,
-         * @cpp false @ce otherwise.
+         * for more information. On failure prints a message to
+         * @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const ImageView1D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
@@ -1374,8 +1377,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const ImageView2D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
@@ -1393,8 +1396,8 @@ class MAGNUM_TRADE_EXPORT AbstractImageConverter: public PluginManager::Abstract
          * non-zero size in all dimensions, and all views sharing the same
          * pixel format. Note that certain converters may impose additional
          * size and order restrictions on the images, see documentation of a
-         * particular plugin for more information. Returns @cpp true @ce on
-         * success, @cpp false @ce otherwise.
+         * particular plugin for more information. On failure prints a message
+         * to @relativeref{Magnum,Error} and returns @cpp false @ce.
          * @see @ref features(), @ref convertToFile(Containers::ArrayView<const ImageView3D>, Containers::StringView),
          *      @ref convert(), @ref convertToData()
          */
diff --git a/src/Magnum/Trade/AbstractImporter.h b/src/Magnum/Trade/AbstractImporter.h
index b0f9f99cb..89e4fadde 100644
--- a/src/Magnum/Trade/AbstractImporter.h
+++ b/src/Magnum/Trade/AbstractImporter.h
@@ -634,7 +634,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * Closes previous file, if it was opened, and tries to open given raw
          * data. Available only if @ref ImporterFeature::OpenData is supported.
-         * Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          *
          * The @p data is not expected to be alive after the function exits.
          * Using @ref openMemory() instead as can avoid unnecessary copies in
@@ -649,7 +650,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * Closes previous file, if it was opened, and tries to open given raw
          * data. Available only if @ref ImporterFeature::OpenData is supported.
-         * Returns @cpp true @ce on success, @cpp false @ce otherwise.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce.
          *
          * Unlike @ref openData(), this function expects @p memory to stay in
          * scope until the importer is destructed, @ref close() is called or
@@ -668,8 +670,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * Closes previous file, if it was opened, and tries to open given
          * state. Available only if @ref ImporterFeature::OpenState is
-         * supported. Returns @cpp true @ce on success, @cpp false @ce
-         * otherwise.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @cpp false @ce.
          *
          * See documentation of a particular plugin for more information about
          * type and contents of the @p state parameter.
@@ -687,12 +689,12 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Open a file
          *
          * Closes previous file, if it was opened, and tries to open given
-         * file. Returns @cpp true @ce on success, @cpp false @ce otherwise.
-         * If file loading callbacks are set via @ref setFileCallback() and
-         * @ref ImporterFeature::OpenData is supported, this function uses the
-         * callback to load the file and passes the memory view to
-         * @ref openData() instead. See @ref setFileCallback() for more
-         * information.
+         * file. On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @cpp false @ce. If file loading callbacks are set via
+         * @ref setFileCallback() and @ref ImporterFeature::OpenData is
+         * supported, this function uses the callback to load the file and
+         * passes the memory view to @ref openData() instead. See
+         * @ref setFileCallback() for more information.
          * @see @ref features(), @ref openData(), @ref openMemory(),
          *      @ref openState()
          */
@@ -784,8 +786,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Scene
          * @param id        Scene ID, from range [0, @ref sceneCount()).
          *
-         * Returns given scene or @ref Containers::NullOpt if import failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref scene(Containers::StringView)
          */
         Containers::Optional<SceneData> scene(UnsignedInt id);
@@ -796,9 +798,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref sceneForName() and
          * @ref scene(UnsignedInt). If @ref sceneForName() returns @cpp -1 @ce,
-         * prints an error message and returns @ref Containers::NullOpt,
-         * otherwise propagates the result from @ref scene(UnsignedInt).
-         * Expects that a file is opened.
+         * prints a message to @relativeref{Magnum,Error} and returns
+         * @ref Containers::NullOpt, otherwise propagates the result from
+         * @ref scene(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<SceneData> scene(Containers::StringView name);
 
@@ -861,8 +863,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Animation
          * @param id    Animation ID, from range [0, @ref animationCount()).
          *
-         * Returns given animation or @ref Containers::NullOpt if importing
-         * failed. Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref animation(Containers::StringView)
          */
         Containers::Optional<AnimationData> animation(UnsignedInt id);
@@ -873,9 +875,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref animationForName() and
          * @ref animation(UnsignedInt). If @ref animationForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref animation(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref animation(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<AnimationData> animation(Containers::StringView name);
 
@@ -910,8 +912,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Light
          * @param id        Light ID, from range [0, @ref lightCount()).
          *
-         * Returns given light or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref light(Containers::StringView)
          */
         Containers::Optional<LightData> light(UnsignedInt id);
@@ -922,9 +924,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref lightForName() and
          * @ref light(UnsignedInt). If @ref lightForName() returns @cpp -1 @ce,
-         * prints an error message and returns @ref Containers::NullOpt,
-         * otherwise propagates the result from @ref light(UnsignedInt).
-         * Expects that a file is opened.
+         * prints a message to @relativeref{Magnum,Error} and returns
+         * @ref Containers::NullOpt, otherwise propagates the result from
+         * @ref light(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<LightData> light(Containers::StringView name);
 
@@ -959,8 +961,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Camera
          * @param id        Camera ID, from range [0, @ref cameraCount()).
          *
-         * Returns given camera or @ref Containers::NullOpt if importing
-         * failed. Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref camera(Containers::StringView)
          */
         Containers::Optional<CameraData> camera(UnsignedInt id);
@@ -971,9 +973,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref cameraForName() and
          * @ref camera(UnsignedInt). If @ref cameraForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref camera(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref camera(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<CameraData> camera(Containers::StringView name);
 
@@ -1144,8 +1146,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param id        Skin ID, from range [0, @ref skin2DCount()).
          * @m_since_latest
          *
-         * Returns given skin or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref skin2D(Containers::StringView)
          */
         Containers::Optional<SkinData2D> skin2D(UnsignedInt id);
@@ -1156,9 +1158,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref skin2DForName() and
          * @ref skin2D(UnsignedInt). If @ref skin2DForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref skin2D(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref skin2D(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<SkinData2D> skin2D(Containers::StringView name);
 
@@ -1197,8 +1199,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param id        Skin ID, from range [0, @ref skin3DCount()).
          * @m_since_latest
          *
-         * Returns given skin or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref skin3D(Containers::StringView)
          */
         Containers::Optional<SkinData3D> skin3D(UnsignedInt id);
@@ -1209,9 +1211,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref skin3DForName() and
          * @ref skin3D(UnsignedInt). If @ref skin3DForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref skin3D(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref skin3D(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<SkinData3D> skin3D(Containers::StringView name);
 
@@ -1262,11 +1264,11 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param level     Mesh level, from range [0, @ref meshLevelCount())
          * @m_since{2020,06}
          *
-         * Returns given mesh or @ref Containers::NullOpt if importing failed.
-         * The @p level parameter allows access to additional data and is
-         * largely left as importer-specific --- for example allowing access to
-         * per-instance, per-face or per-edge data. Expects that a file is
-         * opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. The @p level parameter allows
+         * access to additional data and is largely left as importer-specific
+         * --- for example allowing access to per-instance, per-face or
+         * per-edge data. Expects that a file is opened.
          * @see @ref mesh(Containers::StringView, UnsignedInt),
          *      @ref MeshPrimitive::Instances, @ref MeshPrimitive::Faces,
          *      @ref MeshPrimitive::Edges
@@ -1279,9 +1281,10 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref meshForName() and
          * @ref mesh(UnsignedInt, UnsignedInt). If @ref meshForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref mesh(UnsignedInt, UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref mesh(UnsignedInt, UnsignedInt). Expects that a file is
+         * opened.
          */
         Containers::Optional<MeshData> mesh(Containers::StringView name, UnsignedInt level = 0);
 
@@ -1426,8 +1429,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Material
          * @param id        Material ID, from range [0, @ref materialCount()).
          *
-         * Returns given material or @ref Containers::NullOpt if importing
-         * failed. Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref material(Containers::StringView)
          */
         #if !defined(MAGNUM_BUILD_DEPRECATED) || defined(DOXYGEN_GENERATING_OUTPUT)
@@ -1443,9 +1446,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref materialForName() and
          * @ref material(UnsignedInt). If @ref materialForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref material(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref material(UnsignedInt). Expects that a file is opened.
          */
         #if !defined(MAGNUM_BUILD_DEPRECATED) || defined(DOXYGEN_GENERATING_OUTPUT)
         Containers::Optional<MaterialData>
@@ -1485,8 +1488,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @brief Texture
          * @param id        Texture ID, from range [0, @ref textureCount()).
          *
-         * Returns given texture or @ref Containers::NullOpt if importing
-         * failed. Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref texture(Containers::StringView)
          */
         Containers::Optional<TextureData> texture(UnsignedInt id);
@@ -1497,9 +1500,9 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref textureForName() and
          * @ref texture(UnsignedInt). If @ref textureForName() returns
-         * @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref texture(UnsignedInt). Expects that a file is opened.
+         * @cpp -1 @ce, prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt, otherwise propagates the result
+         * from @ref texture(UnsignedInt). Expects that a file is opened.
          */
         Containers::Optional<TextureData> texture(Containers::StringView name);
 
@@ -1546,8 +1549,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param id        Image ID, from range [0, @ref image1DCount()).
          * @param level     Mip level, from range [0, @ref image1DLevelCount())
          *
-         * Returns given image or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref image1D(Containers::StringView, UnsignedInt)
          */
         Containers::Optional<ImageData1D> image1D(UnsignedInt id, UnsignedInt level = 0);
@@ -1558,10 +1561,10 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref image1DForName() and
          * @ref image1D(UnsignedInt, UnsignedInt). If @ref image1DForName()
-         * returns @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref image1D(UnsignedInt, UnsignedInt). Expects that a file is
-         * opened.
+         * returns @cpp -1 @ce, prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt, otherwise propagates the
+         * result from @ref image1D(UnsignedInt, UnsignedInt). Expects that a
+         * file is opened.
          */
         Containers::Optional<ImageData1D> image1D(Containers::StringView name, UnsignedInt level = 0);
 
@@ -1608,8 +1611,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param id        Image ID, from range [0, @ref image2DCount()).
          * @param level     Mip level, from range [0, @ref image2DLevelCount())
          *
-         * Returns given image or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref image2D(Containers::StringView, UnsignedInt)
          */
         Containers::Optional<ImageData2D> image2D(UnsignedInt id, UnsignedInt level = 0);
@@ -1620,10 +1623,10 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref image2DForName() and
          * @ref image2D(UnsignedInt, UnsignedInt). If @ref image2DForName()
-         * returns @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref image2D(UnsignedInt, UnsignedInt). Expects that a file is
-         * opened.
+         * returns @cpp -1 @ce, prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt, otherwise propagates the
+         * result from @ref image2D(UnsignedInt, UnsignedInt). Expects that a
+         * file is opened.
          */
         Containers::Optional<ImageData2D> image2D(Containers::StringView name, UnsignedInt level = 0);
 
@@ -1670,8 +1673,8 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          * @param id        Image ID, from range [0, @ref image3DCount()).
          * @param level     Mip level, from range [0, @ref image3DLevelCount())
          *
-         * Returns given image or @ref Containers::NullOpt if importing failed.
-         * Expects that a file is opened.
+         * On failure prints a message to @relativeref{Magnum,Error} and
+         * returns @ref Containers::NullOpt. Expects that a file is opened.
          * @see @ref image3D(Containers::StringView, UnsignedInt)
          */
         Containers::Optional<ImageData3D> image3D(UnsignedInt id, UnsignedInt level = 0);
@@ -1682,10 +1685,10 @@ class MAGNUM_TRADE_EXPORT AbstractImporter: public PluginManager::AbstractManagi
          *
          * A convenience API combining @ref image3DForName() and
          * @ref image3D(UnsignedInt, UnsignedInt). If @ref image3DForName()
-         * returns @cpp -1 @ce, prints an error message and returns
-         * @ref Containers::NullOpt, otherwise propagates the result from
-         * @ref image3D(UnsignedInt, UnsignedInt). Expects that a file is
-         * opened.
+         * returns @cpp -1 @ce, prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt, otherwise propagates the
+         * result from @ref image3D(UnsignedInt, UnsignedInt). Expects that a
+         * file is opened.
          */
         Containers::Optional<ImageData3D> image3D(Containers::StringView name, UnsignedInt level = 0);
 
diff --git a/src/Magnum/Trade/AbstractSceneConverter.h b/src/Magnum/Trade/AbstractSceneConverter.h
index fba0a3f26..cb3f46d97 100644
--- a/src/Magnum/Trade/AbstractSceneConverter.h
+++ b/src/Magnum/Trade/AbstractSceneConverter.h
@@ -355,7 +355,8 @@ class MAGNUM_TRADE_EXPORT AbstractSceneConverter: public PluginManager::Abstract
          * Depending on the plugin, can perform for example vertex format
          * conversion, overdraw optimization or decimation / subdivision.
          * Available only if @ref SceneConverterFeature::ConvertMesh is
-         * supported.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @ref Containers::NullOpt.
          * @see @ref features(), @ref convertInPlace(MeshData&)
          */
         Containers::Optional<MeshData> convert(const MeshData& mesh);
@@ -366,9 +367,8 @@ class MAGNUM_TRADE_EXPORT AbstractSceneConverter: public PluginManager::Abstract
          * Depending on the plugin, can perform for example index buffer
          * reordering for better vertex cache use or overdraw optimization.
          * Available only if @ref SceneConverterFeature::ConvertMeshInPlace is
-         * supported. Returns @cpp true @ce if the operation succeeded. On
-         * failure the function prints an error message and returns
-         * @cpp false @ce, @p mesh is guaranteed to stay unchanged.
+         * supported. On failure prints a message to @relativeref{Magnum,Error}
+         * and returns @cpp false @ce, @p mesh is guaranteed to stay unchanged.
          * @see @ref features(), @ref convert(const MeshData&)
          */
         bool convertInPlace(MeshData& mesh);
@@ -379,7 +379,7 @@ class MAGNUM_TRADE_EXPORT AbstractSceneConverter: public PluginManager::Abstract
          * Depending on the plugin, can convert the mesh to a file format that
          * can be saved to disk. Available only if
          * @ref SceneConverterFeature::ConvertMeshToData is supported. On
-         * failure the function prints an error message and returns
+         * failure prints a message to @relativeref{Magnum,Error} and returns
          * @cpp nullptr @ce.
          * @see @ref features(), @ref convertToFile()
          */
@@ -390,9 +390,9 @@ class MAGNUM_TRADE_EXPORT AbstractSceneConverter: public PluginManager::Abstract
          * @m_since_latest
          *
          * Available only if @ref SceneConverterFeature::ConvertMeshToFile or
-         * @ref SceneConverterFeature::ConvertMeshToData is supported. Returns
-         * @cpp true @ce on success, prints an error message and returns
-         * @cpp false @ce otherwise.
+         * @ref SceneConverterFeature::ConvertMeshToData is supported. On
+         * failure prints a message to @relativeref{Magnum,Error} and returns
+         * @cpp false @ce.
          * @see @ref features(), @ref convertToData()
          */
         bool convertToFile(const MeshData& mesh, Containers::StringView filename);