diff --git a/plugins/cargo/_cargo b/plugins/cargo/_cargo
index 99eac2bdb..7ed95c0ce 100644
--- a/plugins/cargo/_cargo
+++ b/plugins/cargo/_cargo
@@ -34,6 +34,7 @@ case $state in
                     '--target=[target triple]: :_get_targets' \
                     '(-v, --verbose)'{-v,--verbose}'[use verbose output]' \
                     '(-q, --quiet)'{-q,--quiet}'[no output printed to stdout]' \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     ;;
 
@@ -51,6 +52,7 @@ case $state in
                     '--target=[target triple]: :_get_targets' \
                     '(-v, --verbose)'{-v,--verbose}'[use verbose output]' \
                     '(-q, --quiet)'{-q,--quiet}'[no output printed to stdout]' \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     ;;
 
@@ -259,12 +261,14 @@ case $state in
                     '--release=[build in release mode]' \
                     '--target=[target triple]' \
                     '(-v, --verbose)'{-v,--verbose}'[use verbose output]' \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     '*: :_normal' \
                     ;;
 
             rustc)
                 _arguments \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     '--features=[features to compile for the package]' \
                     '--all-features[enable all available features]' \
@@ -283,6 +287,7 @@ case $state in
 
             rustdoc)
                 _arguments \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     '--features=[space-separated list of features to also build]' \
                     '--all-features[enable all available features]' \
@@ -325,6 +330,7 @@ case $state in
                     '--release[build artifacts in release mode, with optimizations]' \
                     '--target=[target triple]: :_get_targets' \
                     '(-v, --verbose)'{-v,--verbose}'[use verbose output]' \
+                    '--message-format=[error format]:format option:(human json)' \
                     '--color=[coloring]:colorization option:(auto always never)' \
                     '1: :_test_names' \
                     ;;