diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 7cba40d91..d9a2e13ea 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -3,6 +3,7 @@
 ## New in git-machete 3.40.1
 
 - fixed: ASCII-only mode is now applied separately for stdout and stderr so that stderr retains formatting when stdout is redirected (contributed by @tmchow)
+- improved: bash, zsh and fish completion scripts now consistently filter out mutually exclusive options (contributed by @CodeLine9)
 
 ## New in git-machete 3.40.0
 
diff --git a/ci/checks/prohibit-fish-completion-repetition-checks-for-long-options.sh b/ci/checks/prohibit-fish-completion-repetition-checks-for-long-options.sh
index 804559b4d..266c627f7 100755
--- a/ci/checks/prohibit-fish-completion-repetition-checks-for-long-options.sh
+++ b/ci/checks/prohibit-fish-completion-repetition-checks-for-long-options.sh
@@ -10,7 +10,7 @@ fi
 
 if grep -Pn 'not __fish_seen_subcommand_from .*?--([a-zA-Z0-9-]+)[^a-zA-Z0-9-].*? -x.*? -l \1 .*?-a ' $file; then
   echo
-  echo "In fish completion ($file), flags with required parameter (-x) should not use \`not __fish_seen_subcommand_from <OPTION>\`."
-  echo 'If they do, as of fish v4.1.0, their parameter is not completed (-a) when the flag is used without `=` (`--foo <TAB>`).'
+  echo "In fish completion ($file), a flag \`--<FLAG>\` with required parameter (-x) should not use \`not __fish_seen_subcommand_from <FLAG>\`."
+  echo 'If it does, as of fish v4.1.0, its parameter is not completed (-a) when the flag is used without `=` (`--foo <TAB>`).'
   exit 1
 fi
diff --git a/completion/git-machete.completion.bash b/completion/git-machete.completion.bash
index 32e7a3119..e3c06cac9 100644
--- a/completion/git-machete.completion.bash
+++ b/completion/git-machete.completion.bash
@@ -1,5 +1,49 @@
 #!/usr/bin/env bash
 
+# Check if any of the given options appear in the current command line words.
+# Usage: _git_machete_seen_opt --opt1 -o --opt2 ...
+_git_machete_seen_opt() {
+  local opt
+  for opt in "$@"; do
+    local word
+    for word in "${COMP_WORDS[@]}"; do
+      # Handle options with = (e.g. --onto= matches --onto=* and --onto)
+      if [[ "$opt" == *"=" ]]; then
+        if [[ "$word" == "${opt%=}" || "$word" == "${opt}"* ]]; then
+          return 0
+        fi
+      else
+        if [[ "$word" == "$opt" ]]; then
+          return 0
+        fi
+      fi
+    done
+  done
+  return 1
+}
+
+# Apply mutual exclusion to a space-separated options string.
+# Each subsequent argument is a mutually-exclusive group of options (space-separated).
+# If any option in a group is present on the current command line,
+# all options from that group are removed from the resulting string.
+# Usage: result=$(_git_machete_filter_mutex_groups "<opts>" "<group1>" "<group2>" ...)
+_git_machete_filter_mutex_groups() {
+  local opts=" $1 "
+  shift
+  local group
+  for group in "$@"; do
+    if _git_machete_seen_opt $group; then
+      local opt
+      for opt in $group; do
+        opts="${opts// $opt / }"
+      done
+    fi
+  done
+  opts="${opts# }"
+  opts="${opts% }"
+  echo "$opts"
+}
+
 _git_machete() {
   local cmds="add advance anno completion delete-unmanaged diff discover edit file fork-point github gitlab go help is-managed list log reapply show slide-out squash status traverse update version"
   local help_topics="$cmds config format hooks"
@@ -47,13 +91,29 @@ _git_machete() {
     --stop-after=*) __gitcomp "$(__git_heads)" "" "${cur##--stop-after=}" ;;
     -*)
       case ${COMP_WORDS[2]} in
-        add) __gitcomp "$common_opts $add_opts" ;;
+        add)
+          local filtered_add_opts
+          filtered_add_opts=$(_git_machete_filter_mutex_groups "$add_opts" \
+            "-R --as-root -f --as-first-child" \
+            "-R --as-root -o --onto=")
+          __gitcomp "$common_opts $filtered_add_opts"
+          ;;
         advance) __gitcomp "$common_opts $advance_opts" ;;
-        anno) __gitcomp "$common_opts $anno_opts" ;;
+        anno)
+          local filtered_anno_opts
+          filtered_anno_opts=$(_git_machete_filter_mutex_groups "$anno_opts" \
+            "-H --sync-github-prs -L --sync-gitlab-mrs")
+          __gitcomp "$common_opts $filtered_anno_opts"
+          ;;
         d|diff) __gitcomp "$common_opts $diff_opts" ;;
         delete-unmanaged) __gitcomp "$common_opts $delete_unmanaged_opts" ;;
         discover) __gitcomp "$common_opts $discover_opts" ;;
-        fork-point) __gitcomp "$common_opts $fork_point_opts" ;;
+        fork-point)
+          local filtered_fork_point_opts
+          filtered_fork_point_opts=$(_git_machete_filter_mutex_groups "$fork_point_opts" \
+            "--inferred --override-to= --override-to-inferred --override-to-parent --unset-override")
+          __gitcomp "$common_opts $filtered_fork_point_opts"
+          ;;
         github)
           case ${COMP_WORDS[3]} in
             "anno-prs") __gitcomp "$common_opts $githublab_anno_opts" ;;
@@ -75,11 +135,51 @@ _git_machete() {
             *) __gitcomp "$common_opts" ;;
           esac ;;
         reapply) __gitcomp "$common_opts $reapply_opts" ;;
-        slide-out) __gitcomp "$common_opts $slide_out_opts" ;;
+        slide-out)
+          local filtered_slide_out_opts
+          filtered_slide_out_opts=$(_git_machete_filter_mutex_groups "$slide_out_opts" \
+            "--removed-from-remote -d --down-fork-point=" \
+            "--removed-from-remote -M --merge" \
+            "--removed-from-remote -n" \
+            "--removed-from-remote --no-edit-merge" \
+            "--removed-from-remote --no-interactive-rebase" \
+            "--removed-from-remote --no-rebase" \
+            "-M --merge -d --down-fork-point=" \
+            "-M --merge --no-interactive-rebase" \
+            "-M --merge --no-rebase" \
+            "-n --no-edit-merge" \
+            "-n --no-interactive-rebase" \
+            "--no-rebase -d --down-fork-point=" \
+            "--no-rebase --no-edit-merge" \
+            "--no-rebase --no-interactive-rebase")
+          __gitcomp "$common_opts $filtered_slide_out_opts"
+          ;;
         squash) __gitcomp "$common_opts $squash_opts" ;;
         s|status) __gitcomp "$common_opts $status_opts" ;;
-        t|traverse) __gitcomp "$common_opts $traverse_opts" ;;
-        update) __gitcomp "$common_opts $update_opts" ;;
+        t|traverse)
+          local filtered_traverse_opts
+          filtered_traverse_opts=$(_git_machete_filter_mutex_groups "$traverse_opts" \
+            "-W -F --fetch" \
+            "-W -l --list-commits" \
+            "-W -w --whole" \
+            "-H --sync-github-prs -L --sync-gitlab-mrs" \
+            "-M --merge --no-interactive-rebase" \
+            "-n --no-edit-merge" \
+            "-n --no-interactive-rebase" \
+            "-n -y --yes" \
+            "--push --no-push" \
+            "--push-untracked --no-push-untracked")
+          __gitcomp "$common_opts $filtered_traverse_opts"
+          ;;
+        update)
+          local filtered_update_opts
+          filtered_update_opts=$(_git_machete_filter_mutex_groups "$update_opts" \
+            "-M --merge -f --fork-point=" \
+            "-M --merge --no-interactive-rebase" \
+            "-n --no-edit-merge" \
+            "-n --no-interactive-rebase")
+          __gitcomp "$common_opts $filtered_update_opts"
+          ;;
         *)
           if [[ $COMP_CWORD -eq 2 ]]; then
             __gitcomp "$common_opts --version"
diff --git a/completion/git-machete.completion.zsh b/completion/git-machete.completion.zsh
index 690cc6d67..f214e6711 100644
--- a/completion/git-machete.completion.zsh
+++ b/completion/git-machete.completion.zsh
@@ -19,9 +19,9 @@ _git-machete() {
         (add)
           _arguments \
             '1:: :__git_machete_list_addable' \
-            '(-f --as-first-child)'{-f,--as-first-child}'[Add the given branch as the first (instead of last) child of its parent]' \
-            '(-R --as-root)'{-R,--as-root}'[Add the given branch as a new root]' \
-            '(-o --onto)'{-o,--onto=}'[Specify the target parent branch to add the given branch onto]: :__git_machete_list_managed' \
+            '(-R --as-root -f --as-first-child)'{-f,--as-first-child}'[Add the given branch as the first (instead of last) child of its parent]' \
+            '(-R --as-root -f --as-first-child -o --onto)'{-R,--as-root}'[Add the given branch as a new root]' \
+            '(-R --as-root -o --onto)'{-o,--onto=}'[Specify the target parent branch to add the given branch onto]: :__git_machete_list_managed' \
             '(-y --yes)'{-y,--yes}'[Do not ask for confirmation whether to create the branch or whether to add onto the inferred upstream]' \
             "${common_flags[@]}"
           ;;
@@ -33,8 +33,8 @@ _git-machete() {
         (anno)
           _arguments \
             '(-b --branch)'{-b,--branch=}'[Branch to set the annotation for]: :__git_machete_list_managed' \
-            '(-H --sync-github-prs)'{-H,--sync-github-prs}'[Annotate with GitHub PR numbers and author logins where applicable]' \
-            '(-L --sync-gitlab-mrs)'{-L,--sync-gitlab-mrs}'[Annotate with GitLab MR numbers and author logins where applicable]' \
+            '(-L --sync-gitlab-mrs -H --sync-github-prs)'{-H,--sync-github-prs}'[Annotate with GitHub PR numbers and author logins where applicable]' \
+            '(-H --sync-github-prs -L --sync-gitlab-mrs)'{-L,--sync-gitlab-mrs}'[Annotate with GitLab MR numbers and author logins where applicable]' \
             "${common_flags[@]}"
           ;;
         (completion)
@@ -67,11 +67,11 @@ _git-machete() {
           ;;
         (fork-point)
           _arguments '1:: :__git_branch_names' \
-            '(--inferred)'--inferred'[Display the fork point ignoring any potential override]' \
-            '(--override-to)'--override-to='[Override fork point to the given revision]: :__git_references' \
-            '(--override-to-inferred)'--override-to-inferred'[Override fork point to the inferred location]' \
-            '(--override-to-parent)'--override-to-parent'[Override fork point to the upstream (parent) branch]' \
-            '(--unset-override)'--unset-override='[Unset fork point override by removing machete.overrideForkPoint.<branch>.* configs]: :__git_machete_list_with_overridden_fork_point' \
+            '(--inferred --override-to --override-to-inferred --override-to-parent --unset-override)'--inferred'[Display the fork point ignoring any potential override]' \
+            '(--inferred --override-to --override-to-inferred --override-to-parent --unset-override)'--override-to='[Override fork point to the given revision]: :__git_references' \
+            '(--inferred --override-to --override-to-inferred --override-to-parent --unset-override)'--override-to-inferred'[Override fork point to the inferred location]' \
+            '(--inferred --override-to --override-to-inferred --override-to-parent --unset-override)'--override-to-parent'[Override fork point to the upstream (parent) branch]' \
+            '(--inferred --override-to --override-to-inferred --override-to-parent --unset-override)'--unset-override='[Unset fork point override by removing machete.overrideForkPoint.<branch>.* configs]: :__git_machete_list_with_overridden_fork_point' \
             "${common_flags[@]}"
           ;;
         (g|go)
@@ -115,14 +115,14 @@ _git-machete() {
           # TODO (#113): suggest further branches based on the previous specified branch (like in Bash completion script)
           _arguments \
             '*:: :__git_machete_list_slidable' \
-            '(-d --down-fork-point)'{-d,--down-fork-point=}'[If updating by rebase, specify fork point commit after which the rebased part of history of the downstream branch is meant to start]: :__git_references' \
+            '(--removed-from-remote -M --merge --no-rebase -d --down-fork-point)'{-d,--down-fork-point=}'[If updating by rebase, specify fork point commit after which the rebased part of history of the downstream branch is meant to start]: :__git_references' \
             '(--delete)'--delete'[Delete branches after sliding them out]' \
-            '(-M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
-            '(-n)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
-            '(--no-edit-merge)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
-            '(--no-interactive-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
-            '(--no-rebase)'--no-rebase'[Skip rebase of downstream branches after sliding out]' \
-            '(--removed-from-remote)'--removed-from-remote'[Slide out all branches removed from the remote]' \
+            '(--removed-from-remote -d --down-fork-point --no-interactive-rebase --no-rebase -M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
+            '(--removed-from-remote -n --no-edit-merge --no-interactive-rebase)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
+            '(--removed-from-remote -n --no-edit-merge --no-interactive-rebase --no-rebase)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
+            '(--removed-from-remote -M --merge -n --no-edit-merge --no-interactive-rebase --no-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
+            '(--removed-from-remote -d --down-fork-point -M --merge --no-interactive-rebase --no-edit-merge --no-rebase)'--no-rebase'[Skip rebase of downstream branches after sliding out]' \
+            '(--removed-from-remote -d --down-fork-point -M --merge -n --no-edit-merge --no-interactive-rebase --no-rebase)'--removed-from-remote'[Slide out all branches removed from the remote]' \
             "${common_flags[@]}"
           ;;
         (squash)
@@ -140,34 +140,34 @@ _git-machete() {
           ;;
         (t|traverse)
           _arguments \
-            '(-F --fetch)'{-F,--fetch}'[Fetch the remotes of all managed branches at the beginning of traversal]' \
-            '(-H --sync-github-prs)'{-H,--sync-github-prs}'[Create and retarget GitHub PRs while traversing]' \
-            '(-L --sync-gitlab-mrs)'{-L,--sync-gitlab-mrs}'[Create and retarget GitLab MRs while traversing]' \
-            '(-l --list-commits)'{-l,--list-commits}'[List the messages of commits introduced on each branch]' \
-            '(-M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
-            '(-n)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
+            '(-W -F --fetch)'{-F,--fetch}'[Fetch the remotes of all managed branches at the beginning of traversal]' \
+            '(-L --sync-gitlab-mrs -H --sync-github-prs)'{-H,--sync-github-prs}'[Create and retarget GitHub PRs while traversing]' \
+            '(-H --sync-github-prs -L --sync-gitlab-mrs)'{-L,--sync-gitlab-mrs}'[Create and retarget GitLab MRs while traversing]' \
+            '(-W -l --list-commits)'{-l,--list-commits}'[List the messages of commits introduced on each branch]' \
+            '(--no-interactive-rebase -M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
+            '(-n --no-edit-merge --no-interactive-rebase -y --yes)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
             '(--no-detect-squash-merges)'--no-detect-squash-merges'[Only consider "strict" (fast-forward or 2-parent) merges, rather than rebase/squash merges, when detecting if a branch is merged into its upstream]' \
-            '(--no-edit-merge)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
-            '(--no-interactive-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
-            '(--no-push)'--no-push'[Do not push any (neither tracked nor untracked) branches to remote]' \
-            '(--no-push-untracked)'--no-push-untracked'[Do not push untracked branches to remote]' \
-            '(--push)'--push'[Push all (both tracked and untracked) branches to remote (default behavior)]' \
-            '(--push-untracked)'--push-untracked'[Push untracked branches to remote (default behavior)]' \
+            '(-n --no-edit-merge)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
+            '(-n -M --merge --no-interactive-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
+            '(--push --no-push)'--no-push'[Do not push any (neither tracked nor untracked) branches to remote]' \
+            '(--push-untracked --no-push-untracked)'--no-push-untracked'[Do not push untracked branches to remote]' \
+            '(--no-push --push)'--push'[Push all (both tracked and untracked) branches to remote (default behavior)]' \
+            '(--no-push-untracked --push-untracked)'--push-untracked'[Push untracked branches to remote (default behavior)]' \
             '(--return-to)'--return-to='[The branch to return after traversal is successfully completed; argument can be "here", "nearest-remaining", or "stay"]: :__git_machete_opt_return_to_args' \
             '(--start-from)'--start-from='[The branch to start the traversal from; argument can be "here", "root", "first-root", or any branch name]: :__git_machete_opt_start_from_args_or_branches' \
             '(--stop-after)'--stop-after='[The branch to stop the traversal after]: :__git_branch_names' \
-            '(-w --whole)'{-w,--whole}'[Equivalent to -n --start-from=first-root --return-to=nearest-remaining]' \
-            '(-W)'-W'[Equivalent to --fetch --whole]' \
-            '(-y --yes)'{-y,--yes}'[Do not ask for any interactive input; implicates -n]' \
+            '(-W -w --whole)'{-w,--whole}'[Equivalent to -n --start-from=first-root --return-to=nearest-remaining]' \
+            '(-F --fetch -l --list-commits -w --whole -W)'-W'[Equivalent to --fetch --whole]' \
+            '(-n -y --yes)'{-y,--yes}'[Do not ask for any interactive input; implicates -n]' \
             "${common_flags[@]}"
           ;;
          (update)
           _arguments \
-            '(-f --fork-point)'{-f,--fork-point=}'[If updating by rebase, specify fork point commit after which the rebased part of history is meant to start]: :__git_references' \
-            '(-M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
-            '(-n)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
-            '(--no-edit-merge)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
-            '(--no-interactive-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
+            '(-M --merge -f --fork-point)'{-f,--fork-point=}'[If updating by rebase, specify fork point commit after which the rebased part of history is meant to start]: :__git_references' \
+            '(-f --fork-point --no-interactive-rebase -M --merge)'{-M,--merge}'[Update by merge rather than by rebase]' \
+            '(-n --no-edit-merge --no-interactive-rebase)'-n'[If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge]' \
+            '(-n --no-edit-merge)'--no-edit-merge'[If updating by merge, pass --no-edit flag to underlying git merge]' \
+            '(-n -M --merge --no-interactive-rebase)'--no-interactive-rebase'[If updating by rebase, do NOT pass --interactive flag to underlying git rebase]' \
             "${common_flags[@]}"
           ;;
       esac
diff --git a/completion/git-machete.fish b/completion/git-machete.fish
index 67b80b457..7357799e2 100644
--- a/completion/git-machete.fish
+++ b/completion/git-machete.fish
@@ -194,14 +194,14 @@ complete -c git-machete -n "__fish_seen_subcommand_from show; and not __fish_see
 # git machete slide-out
 complete -c git-machete -n "not __fish_seen_subcommand_from $__machete_commands" -f -a slide-out -d 'Slide out the current branch and sync its downstream (child) branches with its upstream (parent) branch via rebase or merge'
 complete -c git-machete -n "__fish_seen_subcommand_from slide-out"               -f -a '(__machete_slidable_branches)'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote"                                                        -f -l removed-from-remote                         -d 'Slide out all branches removed from the remote'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote --merge -M"                                             -x -l down-fork-point -s d -a '(__fish_git_refs)' -d 'If updating by rebase, specifies the alternative fork point for downstream branches for the operation. Not allowed if updating by merge'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --delete"                                                                     -f -l delete                                      -d 'Delete branches after sliding them out'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote --merge -M --down-fork-point -d"                        -f -l merge           -s M                        -d 'Update the downstream branch by merge rather than by rebase'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -n --no-edit-merge --no-interactive-rebase"             -f                    -s n                        -d 'If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -n --no-edit-merge --no-interactive-rebase"             -f -l no-edit-merge                               -d 'If updating by merge, skip opening the editor for merge commit message while doing git merge (i.e. pass --no-edit flag to underlying git merge). Not allowed if updating by rebase'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -M --merge -n --no-edit-merge --no-interactive-rebase"  -f -l no-interactive-rebase                       -d 'If updating by rebase, run git rebase in non-interactive mode (without -i/--interactive flag). Not allowed if updating by merge'
-complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -d --down-fork-point -n --no-edit-merge --no-rebase"    -f -l no-rebase                                   -d 'Skip rebase of downstream branches after sliding out'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -d --down-fork-point -M --merge -n --no-edit-merge --no-interactive-rebase --no-rebase" -f -l removed-from-remote                         -d 'Slide out all branches removed from the remote'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote --merge -M --no-rebase"                                                        -x -l down-fork-point -s d -a '(__fish_git_refs)' -d 'If updating by rebase, specifies the alternative fork point for downstream branches for the operation. Not allowed if updating by merge'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --delete"                                                                                                  -f -l delete                                      -d 'Delete branches after sliding them out'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote --merge -M --down-fork-point -d --no-rebase"                                          -f -l merge           -s M                        -d 'Update the downstream branch by merge rather than by rebase'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -n --no-edit-merge --no-interactive-rebase"                                           -f                    -s n                        -d 'If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -n --no-edit-merge --no-interactive-rebase --no-rebase"                               -f -l no-edit-merge                               -d 'If updating by merge, skip opening the editor for merge commit message while doing git merge (i.e. pass --no-edit flag to underlying git merge). Not allowed if updating by rebase'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -M --merge -n --no-edit-merge --no-interactive-rebase --no-rebase"                    -f -l no-interactive-rebase                       -d 'If updating by rebase, run git rebase in non-interactive mode (without -i/--interactive flag). Not allowed if updating by merge'
+complete -c git-machete -n "__fish_seen_subcommand_from slide-out; and not __fish_seen_subcommand_from --removed-from-remote -d --down-fork-point -M --merge --no-edit-merge --no-interactive-rebase --no-rebase"  -f -l no-rebase                                   -d 'Skip rebase of downstream branches after sliding out'
 
 # git machete squash
 complete -c git-machete -n "not __fish_seen_subcommand_from $__machete_commands" -f -a squash -d 'Squash the unique history of the current branch into a single commit'
@@ -216,25 +216,25 @@ complete -c git-machete -n "__fish_seen_subcommand_from status s; and not __fish
 
 # git machete traverse
 complete -c git-machete -n "not __fish_seen_subcommand_from $__machete_commands" -f -a traverse -d 'Walk through the tree of branch dependencies and rebase, merge, slide out, push and/or pull each branch one by one'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --fetch -F"                -f -l fetch           -s F                             -d 'Fetch the remotes of all managed branches at the beginning of traversal (no git pull involved, only git fetch)'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --list-commits -l"         -f -l list-commits    -s l                             -d 'When printing the status, additionally list the messages of commits introduced on each branch'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --sync-gitlab-mrs"         -f -l sync-github-prs -s H                             -d 'Create and retarget GitHub PRs while traversing'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --sync-github-prs"         -f -l sync-gitlab-mrs -s L                             -d 'Create and retarget GitLab MRs while traversing'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --merge -M"                -f -l merge           -s M                             -d 'Update by merge rather than by rebase'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --yes -y"                  -f                    -s n                             -d 'If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-detect-squash-merges" -f -l no-detect-squash-merges                          -d 'Only consider "strict" (fast-forward or 2-parent) merges, rather than rebase/squash merges, when detecting if a branch is merged into its upstream (parent)'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-edit-merge"           -f -l no-edit-merge                                    -d 'If updating by merge, skip opening the editor for merge commit message while doing git merge (i.e. pass --no-edit flag to underlying git merge). Not allowed if updating by rebase'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-interactive-rebase"   -f -l no-interactive-rebase                            -d 'If updating by rebase, run git rebase in non-interactive mode (without -i/--interactive flag). Not allowed if updating by merge'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-push"                 -f -l no-push                                          -d 'Do not push any (neither tracked nor untracked) branches to remote, re-enable via --push'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-push-untracked"       -f -l no-push-untracked                                -d 'Do not push untracked branches to remote, re-enable via --push-untracked'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --push"                    -f -l push                                             -d 'Push all (both tracked and untracked) branches to remote - default behavior'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --push-untracked"          -f -l push-untracked                                   -d 'Push untracked branches to remote - default behavior'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                -x -l return-to       -a 'STAY HERE NEAREST-REMAINING' -d 'Specifies the branch to return after traversal is successfully completed'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                -x -l start-from      -a 'HERE ROOT FIRST-ROOT (__fish_git_local_branches)' -d 'Specifies the branch to start the traversal from'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                -x -l stop-after      -a '(__fish_git_local_branches)' -d 'Specifies the branch to stop the traversal after'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --whole -w"                -f -l whole           -s w                             -d 'Equivalent to -n --start-from=first-root --return-to=nearest-remaining'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from -W"                        -f                    -s W                             -d 'Equivalent to --fetch --whole; useful for even more automated traversal of all branches'
-complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --yes -y"                  -f -l yes             -s y                             -d 'Do not ask for any interactive input, including confirmation of rebase/push/pull. Implies -n'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --fetch -F -W"                                       -f -l fetch           -s F                             -d 'Fetch the remotes of all managed branches at the beginning of traversal (no git pull involved, only git fetch)'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --list-commits -l -W"                                -f -l list-commits    -s l                             -d 'When printing the status, additionally list the messages of commits introduced on each branch'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --sync-github-prs -H --sync-gitlab-mrs -L"           -f -l sync-github-prs -s H                             -d 'Create and retarget GitHub PRs while traversing'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --sync-gitlab-mrs -L --sync-github-prs -H"           -f -l sync-gitlab-mrs -s L                             -d 'Create and retarget GitLab MRs while traversing'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --merge -M --no-interactive-rebase"                  -f -l merge           -s M                             -d 'Update by merge rather than by rebase'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from -n --no-edit-merge --no-interactive-rebase --yes -y" -f                    -s n                             -d 'If updating by rebase, equivalent to --no-interactive-rebase. If updating by merge, equivalent to --no-edit-merge'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-detect-squash-merges"                           -f -l no-detect-squash-merges                          -d 'Only consider "strict" (fast-forward or 2-parent) merges, rather than rebase/squash merges, when detecting if a branch is merged into its upstream (parent)'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-edit-merge -n"                                  -f -l no-edit-merge                                    -d 'If updating by merge, skip opening the editor for merge commit message while doing git merge (i.e. pass --no-edit flag to underlying git merge). Not allowed if updating by rebase'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-interactive-rebase -n --merge -M"               -f -l no-interactive-rebase                            -d 'If updating by rebase, run git rebase in non-interactive mode (without -i/--interactive flag). Not allowed if updating by merge'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-push --push"                                    -f -l no-push                                          -d 'Do not push any (neither tracked nor untracked) branches to remote, re-enable via --push'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --no-push-untracked --push-untracked"                -f -l no-push-untracked                                -d 'Do not push untracked branches to remote, re-enable via --push-untracked'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --push --no-push"                                    -f -l push                                             -d 'Push all (both tracked and untracked) branches to remote - default behavior'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --push-untracked --no-push-untracked"                -f -l push-untracked                                   -d 'Push untracked branches to remote - default behavior'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                                          -x -l return-to       -a 'STAY HERE NEAREST-REMAINING' -d 'Specifies the branch to return after traversal is successfully completed'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                                          -x -l start-from      -a 'HERE ROOT FIRST-ROOT (__fish_git_local_branches)' -d 'Specifies the branch to start the traversal from'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t"                                                                                          -x -l stop-after      -a '(__fish_git_local_branches)' -d 'Specifies the branch to stop the traversal after'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --whole -w -W"                                       -f -l whole           -s w                             -d 'Equivalent to -n --start-from=first-root --return-to=nearest-remaining'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from -W --fetch -F --list-commits -l --whole -w"          -f                    -s W                             -d 'Equivalent to --fetch --whole; useful for even more automated traversal of all branches'
+complete -c git-machete -n "__fish_seen_subcommand_from traverse t; and not __fish_seen_subcommand_from --yes -y -n"                                         -f -l yes             -s y                             -d 'Do not ask for any interactive input, including confirmation of rebase/push/pull. Implies -n'
 
 # git machete update
 complete -c git-machete -n "not __fish_seen_subcommand_from $__machete_commands" -f -a update -d 'Sync the current branch with its upstream (parent) branch via rebase or merge'
diff --git a/tests/completion_e2e/test_completion_e2e.py b/tests/completion_e2e/test_completion_e2e.py
index 5680298bc..9b0c2f81a 100644
--- a/tests/completion_e2e/test_completion_e2e.py
+++ b/tests/completion_e2e/test_completion_e2e.py
@@ -27,6 +27,18 @@
         "develop master",
     "git machete add --onto=":
         "develop master",
+    # Mutex: with --as-root on the cmdline,
+    # `-f`/`--as-first-child` and `-o`/`--onto` MUST NOT be suggested.
+    "git machete add --as-root -":
+        "--debug -h --help -v --verbose -y --yes",
+    # Mutex: with --as-root and -f (== --as-first-child) on the cmdline,
+    # `-o`/`--onto` MUST NOT be suggested (mutex with --as-root).
+    "git machete add --as-root -f -":
+        "--debug -h --help -v --verbose -y --yes",
+    # Same mutex case as above, expressed with short flags `-R -f`;
+    # `-o`/`--onto` MUST NOT be suggested.
+    "git machete add -R -f -":
+        "--debug -h --help -v --verbose -y --yes",
     "git machete advance -":
         "--debug -h --help -v --verbose -y --yes",
     "git machete anno -":
@@ -37,6 +49,14 @@
         "develop master",
     "git machete anno --branch=":
         "develop master",
+    # Mutex: with --sync-github-prs (== -H) on the cmdline,
+    # `-L`/`--sync-gitlab-mrs` MUST NOT be suggested.
+    "git machete anno --sync-github-prs -":
+        "-b --branch --debug -h --help -v --verbose",
+    # Mutex: with --sync-gitlab-mrs (== -L) on the cmdline,
+    # `-H`/`--sync-github-prs` MUST NOT be suggested.
+    "git machete anno --sync-gitlab-mrs -":
+        "-b --branch --debug -h --help -v --verbose",
     "git machete completion ":
         "bash fish zsh",
     "git machete delete-unmanaged -":
@@ -57,6 +77,21 @@
         "--debug -h --help --inferred --override-to --override-to-inferred --override-to-parent --unset-override -v --verbose",
     "git machete fork-point --inferred ":
         "develop feature master",
+    # Mutex: with --inferred on the cmdline,
+    # `--override-to=`, `--override-to-parent`, `--override-to-inferred`,
+    # `--unset-override` MUST NOT be suggested.
+    "git machete fork-point --inferred -":
+        "--debug -h --help -v --verbose",
+    # Mutex: with --override-to-parent on the cmdline,
+    # `--inferred`, `--override-to=`, `--override-to-inferred`,
+    # `--unset-override` MUST NOT be suggested.
+    "git machete fork-point --override-to-parent -":
+        "--debug -h --help -v --verbose",
+    # Mutex: with --override-to-inferred on the cmdline,
+    # `--inferred`, `--override-to=`, `--override-to-parent`,
+    # `--unset-override` MUST NOT be suggested.
+    "git machete fork-point --override-to-inferred -":
+        "--debug -h --help -v --verbose",
     "git machete fork-point --override-to=":
         "HEAD develop feature master",
     "git machete fork-point --unset-override ":
@@ -123,6 +158,31 @@
         "--no-edit-merge --no-interactive-rebase --no-rebase --removed-from-remote -v --verbose",
     "git machete slide-out --down-fork-point=":
         "HEAD develop feature master",
+    # Mutex: with --merge on the cmdline, `-d`/`--down-fork-point=`,
+    # `--no-rebase`, `--no-interactive-rebase`, `--removed-from-remote`
+    # MUST NOT be suggested.
+    "git machete slide-out --merge -":
+        "--debug --delete -h --help -n --no-edit-merge -v --verbose",
+    # Same mutex case as above, expressed with the short flag `-M`.
+    "git machete slide-out -M -":
+        "--debug --delete -h --help -n --no-edit-merge -v --verbose",
+    # Mutex: with -n on the cmdline,
+    # `--no-edit-merge`, `--no-interactive-rebase`, `--removed-from-remote`
+    # MUST NOT be suggested.
+    "git machete slide-out -n -":
+        "-M -d --debug --delete --down-fork-point -h --help --merge --no-rebase -v --verbose",
+    # Mutex: with --no-rebase on the cmdline,
+    # `-d`/`--down-fork-point=`, `-M`/`--merge`, `--no-edit-merge`,
+    # `--no-interactive-rebase`, `--removed-from-remote`
+    # MUST NOT be suggested.
+    "git machete slide-out --no-rebase -":
+        "--debug --delete -h --help -n -v --verbose",
+    # Mutex: with --removed-from-remote on the cmdline,
+    # `-d`/`--down-fork-point=`, `-M`/`--merge`, `-n`, `--no-edit-merge`,
+    # `--no-interactive-rebase`, `--no-rebase` MUST NOT be suggested
+    # (only `--delete` is compatible with --removed-from-remote).
+    "git machete slide-out --removed-from-remote -":
+        "--debug --delete -h --help -v --verbose",
     "git machete squash -":
         "--debug -f --fork-point -h --help -v --verbose",
     "git machete squash --fork-point ":
@@ -163,10 +223,94 @@
         "develop feature master",
     "git machete traverse --stop-after=":
         "develop feature master",
+    # Mutex: with --push on the cmdline, `--no-push` MUST NOT be suggested.
+    "git machete traverse --push -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "-n --no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push-untracked --push-untracked --return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with --no-push on the cmdline, `--push` MUST NOT be suggested.
+    "git machete traverse --no-push -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "-n --no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push-untracked --push-untracked --return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with --push-untracked on the cmdline,
+    # `--no-push-untracked` MUST NOT be suggested.
+    "git machete traverse --push-untracked -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "-n --no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push --push --return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with --no-push-untracked on the cmdline,
+    # `--push-untracked` MUST NOT be suggested.
+    "git machete traverse --no-push-untracked -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "-n --no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push --push --return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with -W (== --fetch + --whole) on the cmdline,
+    # `-F`/`--fetch`, `-l`/`--list-commits`, `-w`/`--whole` MUST NOT be suggested.
+    "git machete traverse -W -":
+        "-H -L -M --debug -h --help --merge -n --no-detect-squash-merges "
+        "--no-edit-merge --no-interactive-rebase --no-push --no-push-untracked "
+        "--push --push-untracked --return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -y --yes",
+    # Mutex: with -F (== --fetch) on the cmdline, `-W` MUST NOT be suggested
+    # (since -W implies --fetch + --whole).
+    "git machete traverse -F -":
+        "-H -L -M --debug -h --help -l --list-commits --merge -n "
+        "--no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with -H (== --sync-github-prs) on the cmdline,
+    # `-L`/`--sync-gitlab-mrs` MUST NOT be suggested.
+    "git machete traverse -H -":
+        "-F -M -W --debug --fetch -h --help -l --list-commits --merge -n "
+        "--no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after -v --verbose -w --whole -y --yes",
+    # Mutex: with -M (== --merge) on the cmdline,
+    # `--no-interactive-rebase` MUST NOT be suggested.
+    "git machete traverse -M -":
+        "-F -H -L -W --debug --fetch -h --help -l --list-commits -n "
+        "--no-detect-squash-merges --no-edit-merge "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with -n on the cmdline,
+    # `--no-edit-merge`, `--no-interactive-rebase`, `-y`/`--yes` MUST NOT be suggested.
+    "git machete traverse -n -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "--no-detect-squash-merges "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole",
+    # Mutex: with --no-interactive-rebase on the cmdline,
+    # `-n` and `-M`/`--merge` MUST NOT be suggested.
+    "git machete traverse --no-interactive-rebase -":
+        "-F -H -L -W --debug --fetch -h --help -l --list-commits "
+        "--no-detect-squash-merges --no-edit-merge "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole -y --yes",
+    # Mutex: with -y (== --yes) on the cmdline, `-n` MUST NOT be suggested
+    # (since --yes implies -n).
+    "git machete traverse -y -":
+        "-F -H -L -M -W --debug --fetch -h --help -l --list-commits --merge "
+        "--no-detect-squash-merges --no-edit-merge --no-interactive-rebase "
+        "--no-push --no-push-untracked --push --push-untracked "
+        "--return-to --start-from --stop-after "
+        "--sync-github-prs --sync-gitlab-mrs -v --verbose -w --whole",
     "git machete update -":
         "-M --debug -f --fork-point -h --help --merge -n --no-edit-merge --no-interactive-rebase -v --verbose",
     "git machete update -f ":
         "HEAD develop feature master",
+    # Mutex: with -n on the cmdline,
+    # `--no-edit-merge` and `--no-interactive-rebase` MUST NOT be suggested.
+    "git machete update -n -":
+        "-M --debug -f --fork-point -h --help --merge -v --verbose",
     "git machete version ":
         ""
 }