diff --git a/Sources/ArgumentParser/Completions/CompletionsGenerator.swift b/Sources/ArgumentParser/Completions/CompletionsGenerator.swift
index 5328e798c..d1370b6ce 100644
--- a/Sources/ArgumentParser/Completions/CompletionsGenerator.swift
+++ b/Sources/ArgumentParser/Completions/CompletionsGenerator.swift
@@ -124,11 +124,14 @@ struct CompletionsGenerator {
     CompletionShell._requesting.withLock { $0 = shell }
     switch shell {
     case .zsh:
-      return ToolInfoV0(commandStack: [command]).zshCompletionScript
+      return ToolInfoV0(commandStack: [command], includeHiddenArguments: true)
+        .zshCompletionScript
     case .bash:
-      return ToolInfoV0(commandStack: [command]).bashCompletionScript
+      return ToolInfoV0(commandStack: [command], includeHiddenArguments: true)
+        .bashCompletionScript
     case .fish:
-      return ToolInfoV0(commandStack: [command]).fishCompletionScript
+      return ToolInfoV0(commandStack: [command], includeHiddenArguments: true)
+        .fishCompletionScript
     default:
       fatalError("Invalid CompletionShell: \(shell)")
     }
diff --git a/Sources/ArgumentParser/Usage/DumpHelpGenerator.swift b/Sources/ArgumentParser/Usage/DumpHelpGenerator.swift
index 002d564f5..d01e94d97 100644
--- a/Sources/ArgumentParser/Usage/DumpHelpGenerator.swift
+++ b/Sources/ArgumentParser/Usage/DumpHelpGenerator.swift
@@ -43,19 +43,28 @@ extension BidirectionalCollection where Element == ParsableCommand.Type {
 }
 
 extension ToolInfoV0 {
-  init(commandStack: [ParsableCommand.Type]) {
-    self.init(command: CommandInfoV0(commandStack: commandStack))
+  init(
+    commandStack: [ParsableCommand.Type], includeHiddenArguments: Bool = false
+  ) {
+    self.init(
+      command: CommandInfoV0(
+        commandStack: commandStack,
+        includeHiddenArguments: includeHiddenArguments))
     // FIXME: This is a hack to inject the help command into the tool info
     // instead we should try to lift this into the parseable command tree
     self.command.subcommands =
       (self.command.subcommands ?? []) + [
-        CommandInfoV0(commandStack: commandStack + [HelpCommand.self])
+        CommandInfoV0(
+          commandStack: commandStack + [HelpCommand.self],
+          includeHiddenArguments: includeHiddenArguments)
       ]
   }
 }
 
 extension CommandInfoV0 {
-  fileprivate init(commandStack: [ParsableCommand.Type]) {
+  fileprivate init(
+    commandStack: [ParsableCommand.Type], includeHiddenArguments: Bool
+  ) {
     guard let command = commandStack.last else {
       preconditionFailure("commandStack must not be empty")
     }
@@ -72,12 +81,17 @@ extension CommandInfoV0 {
       .map { subcommand -> CommandInfoV0 in
         var commandStack = commandStack
         commandStack.append(subcommand)
-        return CommandInfoV0(commandStack: commandStack)
+        return CommandInfoV0(
+          commandStack: commandStack,
+          includeHiddenArguments: includeHiddenArguments)
       }
     let arguments =
       commandStack
       .allArguments()
-      .compactMap(ArgumentInfoV0.init)
+      .compactMap {
+        ArgumentInfoV0(
+          argument: $0, includeHiddenArguments: includeHiddenArguments)
+      }
 
     self = CommandInfoV0(
       superCommands: superCommands,
@@ -93,7 +107,8 @@ extension CommandInfoV0 {
 }
 
 extension ArgumentInfoV0 {
-  fileprivate init?(argument: ArgumentDefinition) {
+  fileprivate init?(argument: ArgumentDefinition, includeHiddenArguments: Bool)
+  {
     guard let kind = ArgumentInfoV0.KindV0(argument: argument) else {
       return nil
     }
@@ -112,9 +127,15 @@ extension ArgumentInfoV0 {
       allValueDescriptions = options.allValueDescriptions
     }
 
+    // When building for completions (includeHiddenArguments == true), mark
+    // hidden arguments as displayable so completion scripts include them.
+    // Private arguments remain non-displayable in both cases.
+    let shouldDisplay = argument.help.visibility.isAtLeastAsVisible(
+      as: includeHiddenArguments ? .hidden : .default)
+
     self.init(
       kind: kind,
-      shouldDisplay: argument.help.visibility.base == .default,
+      shouldDisplay: shouldDisplay,
       sectionTitle: argument.help.parentTitle.nonEmpty,
       isOptional: argument.help.options.contains(.isOptional),
       isRepeating: argument.help.options.contains(.isRepeating),
diff --git a/Tests/ArgumentParserExampleTests/Snapshots/testMathBashCompletionScript().bash b/Tests/ArgumentParserExampleTests/Snapshots/testMathBashCompletionScript().bash
index b96d7ace9..ed358a365 100644
--- a/Tests/ArgumentParserExampleTests/Snapshots/testMathBashCompletionScript().bash
+++ b/Tests/ArgumentParserExampleTests/Snapshots/testMathBashCompletionScript().bash
@@ -249,13 +249,16 @@ _math_stats_stdev() {
 
 _math_stats_quantiles() {
     repeating_flags=()
-    non_repeating_flags=(--version -h --help)
+    non_repeating_flags=(--test-success-exit-code --test-failure-exit-code --test-validation-exit-code --version -h --help)
     repeating_options=()
-    non_repeating_options=(--file --directory --shell --custom --custom-deprecated)
+    non_repeating_options=(--test-custom-exit-code --file --directory --shell --custom --custom-deprecated)
     __math_offer_flags_options -1
 
     # Offer option value completions
     case "${prev}" in
+    '--test-custom-exit-code')
+        return
+        ;;
     '--file')
         __math_add_completions -o plusdirs -fX '!*.@(txt|md)'
         return
diff --git a/Tests/ArgumentParserExampleTests/Snapshots/testMathFishCompletionScript().fish b/Tests/ArgumentParserExampleTests/Snapshots/testMathFishCompletionScript().fish
index 0fd19c10d..1d92835b8 100644
--- a/Tests/ArgumentParserExampleTests/Snapshots/testMathFishCompletionScript().fish
+++ b/Tests/ArgumentParserExampleTests/Snapshots/testMathFishCompletionScript().fish
@@ -41,7 +41,7 @@ function __math_parse_tokens -S
             case 'stdev'
                 __math_parse_subcommand -r 1 'version' 'h/help'
             case 'quantiles'
-                __math_parse_subcommand -r 4 'file=' 'directory=' 'shell=' 'custom=' 'custom-deprecated=' 'version' 'h/help'
+                __math_parse_subcommand -r 4 'test-success-exit-code' 'test-failure-exit-code' 'test-validation-exit-code' 'test-custom-exit-code=' 'file=' 'directory=' 'shell=' 'custom=' 'custom-deprecated=' 'version' 'h/help'
             end
         case 'help'
             __math_parse_subcommand -r 1 'version'
@@ -130,6 +130,10 @@ complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "mat
 complete -c 'math' -n '__math_should_offer_completions_for_positional "math stats quantiles" 1' -fka 'alphabet alligator branch braggart'
 complete -c 'math' -n '__math_should_offer_completions_for_positional "math stats quantiles" 2' -fka '(__math_custom_completion ---completion stats quantiles -- positional@1 (count (__math_tokens -pc)) (__math_tokens -tC))'
 complete -c 'math' -n '__math_should_offer_completions_for_positional "math stats quantiles" 3' -fka '(__math_custom_completion ---completion stats quantiles -- positional@2)'
+complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" test-success-exit-code' -l 'test-success-exit-code'
+complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" test-failure-exit-code' -l 'test-failure-exit-code'
+complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" test-validation-exit-code' -l 'test-validation-exit-code'
+complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" test-custom-exit-code' -l 'test-custom-exit-code' -rfka ''
 complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" file' -l 'file' -rfa '(set -l exts \'txt\' \'md\';for p in (string match -e -- \'*/\' (commandline -t);or printf \n)*.{$exts};printf %s\n $p;end;__fish_complete_directories (commandline -t) \'\')'
 complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" directory' -l 'directory' -rfa '(__math_complete_directories)'
 complete -c 'math' -n '__math_should_offer_completions_for_flags_or_options "math stats quantiles" shell' -l 'shell' -rfka '(head -100 \'/usr/share/dict/words\' | tail -50)'
diff --git a/Tests/ArgumentParserExampleTests/Snapshots/testMathZshCompletionScript().zsh b/Tests/ArgumentParserExampleTests/Snapshots/testMathZshCompletionScript().zsh
index 0f5518ba8..9fc6d6a19 100644
--- a/Tests/ArgumentParserExampleTests/Snapshots/testMathZshCompletionScript().zsh
+++ b/Tests/ArgumentParserExampleTests/Snapshots/testMathZshCompletionScript().zsh
@@ -159,6 +159,10 @@ _math_stats_quantiles() {
         ':custom-arg:{__math_custom_complete ---completion stats quantiles -- positional@1 "${current_word_index}" "$(__math_cursor_index_in_current_word)"}'
         ':custom-deprecated-arg:{__math_custom_complete ---completion stats quantiles -- positional@2}'
         '*:values:'
+        '--test-success-exit-code'
+        '--test-failure-exit-code'
+        '--test-validation-exit-code'
+        '--test-custom-exit-code:test-custom-exit-code:'
         '--file:file:_files -g '\''*.txt *.md'\'''
         '--directory:directory:_files -/'
         '--shell:shell:{local -a list;list=(${(f)"$(head -100 '\''/usr/share/dict/words'\'' | tail -50)"});_describe -V "" list}'
diff --git a/Tests/ArgumentParserUnitTests/CompletionScriptTests.swift b/Tests/ArgumentParserUnitTests/CompletionScriptTests.swift
index d34d71aaf..d395d3d76 100644
--- a/Tests/ArgumentParserUnitTests/CompletionScriptTests.swift
+++ b/Tests/ArgumentParserUnitTests/CompletionScriptTests.swift
@@ -280,3 +280,93 @@ extension CompletionScriptTests {
     try await assertCustomCompletions(shell: .zsh)
   }
 }
+
+// MARK: - Hidden and private visibility tests
+
+extension CompletionScriptTests {
+  /// A command with arguments at each visibility level to verify that
+  /// completion scripts include hidden arguments but exclude private ones.
+  struct Visibility: ParsableCommand {
+    static let configuration = CommandConfiguration(
+      commandName: "visibility-test")
+
+    @Flag(help: ArgumentHelp("A default flag.", visibility: .default))
+    var defaultFlag = false
+
+    @Flag(help: ArgumentHelp("A hidden flag.", visibility: .hidden))
+    var hiddenFlag = false
+
+    @Flag(help: ArgumentHelp("A private flag.", visibility: .private))
+    var privateFlag = false
+
+    @Option(
+      help: ArgumentHelp("A hidden option.", visibility: .hidden),
+      completion: .list(["hidden-a", "hidden-b"]))
+    var hiddenOption: String?
+
+    @Option(
+      help: ArgumentHelp("A private option.", visibility: .private),
+      completion: .list(["private-a", "private-b"]))
+    var privateOption: String?
+  }
+
+  func testHiddenAndPrivateBash() throws {
+    let script = try CompletionsGenerator(
+      command: Visibility.self, shell: .bash
+    )
+    .generateCompletionScript()
+    // Hidden args should appear in completions.
+    XCTAssert(
+      script.contains("--hidden-flag"),
+      "Expected --hidden-flag in bash completion")
+    XCTAssert(
+      script.contains("--hidden-option"),
+      "Expected --hidden-option in bash completion")
+    // Private args must not appear.
+    XCTAssertFalse(
+      script.contains("--private-flag"),
+      "Expected --private-flag absent from bash completion")
+    XCTAssertFalse(
+      script.contains("--private-option"),
+      "Expected --private-option absent from bash completion")
+  }
+
+  func testHiddenAndPrivateFish() throws {
+    let script = try CompletionsGenerator(
+      command: Visibility.self, shell: .fish
+    )
+    .generateCompletionScript()
+    // Hidden args should appear in completions.
+    XCTAssert(
+      script.contains("hidden-flag"), "Expected hidden-flag in fish completion")
+    XCTAssert(
+      script.contains("hidden-option"),
+      "Expected hidden-option in fish completion")
+    // Private args must not appear.
+    XCTAssertFalse(
+      script.contains("private-flag"),
+      "Expected private-flag absent from fish completion")
+    XCTAssertFalse(
+      script.contains("private-option"),
+      "Expected private-option absent from fish completion")
+  }
+
+  func testHiddenAndPrivateZsh() throws {
+    let script = try CompletionsGenerator(command: Visibility.self, shell: .zsh)
+      .generateCompletionScript()
+    // Hidden args should appear in completions.
+    XCTAssert(
+      script.contains("--hidden-flag"),
+      "Expected --hidden-flag in zsh completion")
+    XCTAssert(
+      script.contains("--hidden-option"),
+      "Expected --hidden-option in zsh completion")
+    // Private args must not appear.
+    XCTAssertFalse(
+      script.contains("--private-flag"),
+      "Expected --private-flag absent from zsh completion")
+    XCTAssertFalse(
+      script.contains("--private-option"),
+      "Expected --private-option absent from zsh completion")
+  }
+}
diff --git a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Bash().bash b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Bash().bash
index 95b84438d..fb1cdc3ed 100644
--- a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Bash().bash
+++ b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Bash().bash
@@ -163,7 +163,7 @@ _base-test() {
     local -a unparsed_words=("${COMP_WORDS[@]:1:${COMP_CWORD}}")
 
     local -a repeating_flags=(--kind-counter)
-    local -a non_repeating_flags=(--one --two --custom-three -h --help)
+    local -a non_repeating_flags=(--verbose --one --two --custom-three -h --help)
     local -a repeating_options=(--rep1 -r --rep2)
     local -a non_repeating_options=(--name --kind --other-kind --path1 --path2 --path3)
     __base-test_offer_flags_options 2
diff --git a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Fish().fish b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Fish().fish
index df9e309b8..a8a2ab953 100644
--- a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Fish().fish
+++ b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Fish().fish
@@ -27,7 +27,7 @@ function __base-test_parse_tokens -S
 
     switch $unparsed_tokens[1]
     case 'base-test'
-        __base-test_parse_subcommand 2 'name=' 'kind=' 'other-kind=' 'path1=' 'path2=' 'path3=' 'one' 'two' 'custom-three' 'kind-counter' 'rep1=+' 'r/rep2=+' 'h/help'
+        __base-test_parse_subcommand 2 'name=' 'kind=' 'other-kind=' 'path1=' 'path2=' 'path3=' 'verbose' 'one' 'two' 'custom-three' 'kind-counter' 'rep1=+' 'r/rep2=+' 'h/help'
         switch $unparsed_tokens[1]
         case 'sub-command'
             __base-test_parse_subcommand 0 'h/help'
@@ -101,6 +101,7 @@ complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_op
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" path1' -l 'path1' -rF
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" path2' -l 'path2' -rF
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" path3' -l 'path3' -rfka 'c1_fish c2_fish c3_fish'
+complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" verbose' -l 'verbose'
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" one' -l 'one'
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" two' -l 'two'
 complete -c 'base-test' -n '__base-test_should_offer_completions_for_flags_or_options "base-test" custom-three' -l 'custom-three'
diff --git a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Zsh().zsh b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Zsh().zsh
index 6d8eb1aa8..58f648ab5 100644
--- a/Tests/ArgumentParserUnitTests/Snapshots/testBase_Zsh().zsh
+++ b/Tests/ArgumentParserUnitTests/Snapshots/testBase_Zsh().zsh
@@ -50,6 +50,7 @@ _base-test() {
         '--path1:path1:_files'
         '--path2:path2:_files'
         '--path3:path3:{__base-test_complete "${___path3[@]}"}'
+        '--verbose'
         '--one'
         '--two'
         '--custom-three'