diff --git a/src/aphront/AphrontRequest.php b/src/aphront/AphrontRequest.php
--- a/src/aphront/AphrontRequest.php
+++ b/src/aphront/AphrontRequest.php
@@ -780,9 +780,9 @@
    *
    * @param   string        $name Canonical header name, like
         `"Accept-Encoding"`.
-   * @param   wild?         $default Default value to return if header is not
-        present.
-   * @param   array?        $data Read this instead of `$_SERVER`.
+   * @param   wild          $default (optional) Default value to return if
+        header is not present.
+   * @param   array         $data (optional) Read this instead of `$_SERVER`.
    * @return  string|wild   Header value if present, or `$default` if not.
    */
   public static function getHTTPHeader($name, $default = null, $data = null) {
diff --git a/src/aphront/sink/AphrontHTTPSink.php b/src/aphront/sink/AphrontHTTPSink.php
--- a/src/aphront/sink/AphrontHTTPSink.php
+++ b/src/aphront/sink/AphrontHTTPSink.php
@@ -29,7 +29,7 @@
    * Write an HTTP status code to the output.
    *
    * @param int $code Numeric HTTP status code.
-   * @param string? $message
+   * @param string $message (optional)
    * @return void
    */
   final public function writeHTTPStatus($code, $message = '') {
diff --git a/src/applications/auth/constants/PhabricatorCookies.php b/src/applications/auth/constants/PhabricatorCookies.php
--- a/src/applications/auth/constants/PhabricatorCookies.php
+++ b/src/applications/auth/constants/PhabricatorCookies.php
@@ -107,8 +107,8 @@
    *
    * @param   AphrontRequest    $request Request to write to.
    * @param   string            $next_uri URI to write.
-   * @param   bool?             $force Write this cookie even if we have a
-   *                            fresh cookie already.
+   * @param   bool              $force (optional) Write this cookie even if we
+   *                            have a fresh cookie already.
    * @return  void
    *
    * @task next
diff --git a/src/applications/auth/controller/PhabricatorAuthController.php b/src/applications/auth/controller/PhabricatorAuthController.php
--- a/src/applications/auth/controller/PhabricatorAuthController.php
+++ b/src/applications/auth/controller/PhabricatorAuthController.php
@@ -45,8 +45,8 @@
    * event and do something else if they prefer.
    *
    * @param   PhabricatorUser $user User to log the viewer in as.
-   * @param bool? $force_full_session True to issue a full session immediately,
-   *   bypassing MFA.
+   * @param bool $force_full_session (optional) True to issue a full session
+   *   immediately, bypassing MFA.
    * @return  AphrontResponse   Response which continues the login process.
    */
   protected function loginUser(
diff --git a/src/applications/auth/engine/PhabricatorAuthSessionEngine.php b/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
--- a/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
+++ b/src/applications/auth/engine/PhabricatorAuthSessionEngine.php
@@ -327,7 +327,7 @@
    * multifactor authentication.
    *
    * @param PhabricatorUser $user User whose sessions should be terminated.
-   * @param string|null? $except_session Optionally, one session to keep.
+   * @param string|null $except_session (optional) One session to keep.
    *   Normally, the current login session.
    *
    * @return void
@@ -428,9 +428,9 @@
    * @param AphrontRequest  $request Current request.
    * @param string          $cancel_uri URI to return the user to if they
    *                        cancel.
-   * @param bool?           $jump_into_hisec True to jump partial sessions
-   *                        directly into high security instead of just
-   *                        upgrading them to full sessions.
+   * @param bool            $jump_into_hisec (optional) True to jump partial
+   *                        sessions directly into high security instead of
+   *                        just upgrading them to full sessions.
    * @return PhabricatorAuthHighSecurityToken Security token.
    * @task hisec
    */
@@ -742,7 +742,7 @@
    * Issue a high security token for a session, if authorized.
    *
    * @param PhabricatorAuthSession $session Session to issue a token for.
-   * @param bool? $force Force token issue.
+   * @param bool $force (optional) Force token issue.
    * @return PhabricatorAuthHighSecurityToken|null Token, if authorized.
    * @task hisec
    */
@@ -945,11 +945,11 @@
    * @param PhabricatorUser $user User to generate a URI for.
    * @param PhabricatorUserEmail? $email Optionally, email to verify when
    *  link is used.
-   * @param string? $type Optional context string for the URI. This is purely
+   * @param string $type (optional) Context string for the URI. This is purely
    *  cosmetic and used only to customize workflow and error messages.
-   * @param bool? $force_full_session True to generate a URI which forces an
-   *  immediate upgrade to a full session, bypassing MFA and other login
-   *  checks.
+   * @param bool $force_full_session (optional) True to generate a URI which
+   *  forces an immediate upgrade to a full session, bypassing MFA and other
+   *  login checks.
    * @return string Login URI.
    * @task onetime
    */
@@ -994,9 +994,10 @@
    * Load the temporary token associated with a given one-time login key.
    *
    * @param PhabricatorUser $user User to load the token for.
-   * @param PhabricatorUserEmail? $email Optionally, email to verify when
-   *  link is used.
-   * @param string? $key Key user is presenting as a valid one-time login key.
+   * @param PhabricatorUserEmail $email (optional) Email to verify when link is
+   *   used.
+   * @param string $key (optional) Key user is presenting as a valid one-time
+   *   login key.
    * @return PhabricatorAuthTemporaryToken|null Token, if one exists.
    * @task onetime
    */
@@ -1022,9 +1023,9 @@
    * Hash a one-time login key for storage as a temporary token.
    *
    * @param PhabricatorUser $user User this key is for.
-   * @param PhabricatorUserEmail? $email Optionally, email to verify when
-   *  link is used.
-   * @param string? $key The one time login key.
+   * @param PhabricatorUserEmail $email (optional) Email to verify when link is
+   *   used.
+   * @param string $key (optional) The one time login key.
    * @return string Hash of the key.
    * task onetime
    */
diff --git a/src/applications/auth/provider/PhabricatorAuthProvider.php b/src/applications/auth/provider/PhabricatorAuthProvider.php
--- a/src/applications/auth/provider/PhabricatorAuthProvider.php
+++ b/src/applications/auth/provider/PhabricatorAuthProvider.php
@@ -462,7 +462,8 @@
    *
    * @param   AphrontRequest $request HTTP request.
    * @param   string         $mode Request mode string.
-   * @param   map?           $attributes Additional parameters, see above.
+   * @param   map            $attributes (optional) Additional parameters, see
+   *   above.
    * @return  wild            Log in button.
    */
   protected function renderStandardLoginButton(
diff --git a/src/applications/base/PhabricatorApplication.php b/src/applications/base/PhabricatorApplication.php
--- a/src/applications/base/PhabricatorApplication.php
+++ b/src/applications/base/PhabricatorApplication.php
@@ -331,8 +331,8 @@
    * Build items for the main menu.
    *
    * @param  PhabricatorUser    $user The viewing user.
-   * @param  AphrontController? $controller The current controller. May be null
-   *   for special pages like 404, exception handlers, etc.
+   * @param  AphrontController  $controller (optional) The current controller.
+   *   May be null for special pages like 404, exception handlers, etc.
    * @return list<PHUIListItemView> List of menu items.
    * @task ui
    */
diff --git a/src/applications/celerity/api.php b/src/applications/celerity/api.php
--- a/src/applications/celerity/api.php
+++ b/src/applications/celerity/api.php
@@ -11,7 +11,7 @@
  *
  * @param string $symbol Name of the celerity module to include. This is
  *               whatever you annotated as "@provides" in the file.
- * @param string? $source_name
+ * @param string $source_name (optional)
  * @return void
  */
 function require_celerity_resource($symbol, $source_name = 'phabricator') {
@@ -42,7 +42,7 @@
  * Get the versioned URI for a raw resource, like an image.
  *
  * @param   string  $resource Path to the raw image.
- * @param   string? $source
+ * @param   string  $source (optional) Defaults to 'phabricator'
  * @return  string  Versioned path to the image, if one is available.
  */
 function celerity_get_resource_uri($resource, $source = 'phabricator') {
diff --git a/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php b/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
--- a/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
+++ b/src/applications/differential/render/DifferentialChangesetHTMLRenderer.php
@@ -494,7 +494,7 @@
    * @param int $top Beginning of the line range to build links for.
    * @param int $len Length of the line range to build links for.
    * @param int $changeset_length Total number of lines in the changeset.
-   * @param bool? $is_blocks
+   * @param bool $is_blocks (optional)
    * @return markup Rendered links.
    */
   protected function renderShowContextLinks(
diff --git a/src/applications/diffusion/data/DiffusionGitBranch.php b/src/applications/diffusion/data/DiffusionGitBranch.php
--- a/src/applications/diffusion/data/DiffusionGitBranch.php
+++ b/src/applications/diffusion/data/DiffusionGitBranch.php
@@ -20,8 +20,8 @@
    *   );
    *
    * @param string $stdout stdout of git branch command.
-   * @param string? $only_this_remote Filter branches to those on a specific
-   *   remote.
+   * @param string $only_this_remote (optional) Filter branches to those on a
+   *   specific remote.
    * @return map Map of 'branch' or 'remote/branch' to hash at HEAD.
    */
   public static function parseRemoteBranchOutput(
diff --git a/src/applications/diffusion/request/DiffusionRequest.php b/src/applications/diffusion/request/DiffusionRequest.php
--- a/src/applications/diffusion/request/DiffusionRequest.php
+++ b/src/applications/diffusion/request/DiffusionRequest.php
@@ -135,7 +135,7 @@
    *
    * @param   string            $identifier  Repository identifier.
    * @param   PhabricatorUser   $viewer  Viewing user.
-   * @param   bool?             $need_edit
+   * @param   bool              $need_edit (optional)
    * @return  DiffusionRequest    New request object.
    * @task new
    */
diff --git a/src/applications/files/PhabricatorImageTransformer.php b/src/applications/files/PhabricatorImageTransformer.php
--- a/src/applications/files/PhabricatorImageTransformer.php
+++ b/src/applications/files/PhabricatorImageTransformer.php
@@ -21,7 +21,7 @@
    * extensions), but can save images in another format.
    *
    * @param   resource  $data GD image resource.
-   * @param   string?   $preferred_mime Optionally, preferred mime type.
+   * @param   string    $preferred_mime (optional) Preferred mime type.
    * @return  string    Bytes of an image file.
    * @task save
    */
diff --git a/src/applications/files/storage/PhabricatorFile.php b/src/applications/files/storage/PhabricatorFile.php
--- a/src/applications/files/storage/PhabricatorFile.php
+++ b/src/applications/files/storage/PhabricatorFile.php
@@ -807,8 +807,8 @@
   /**
    * Return an iterable which emits file content bytes.
    *
-   * @param int? $begin Offset for the start of data.
-   * @param int? $end Offset for the end of data.
+   * @param int $begin (optional) Offset for the start of data.
+   * @param int $end (optional) Offset for the end of data.
    * @return Iterable Iterable object which emits requested data.
    */
   public function getFileDataIterator($begin = null, $end = null) {
diff --git a/src/applications/meta/panel/PhabricatorApplicationConfigurationPanel.php b/src/applications/meta/panel/PhabricatorApplicationConfigurationPanel.php
--- a/src/applications/meta/panel/PhabricatorApplicationConfigurationPanel.php
+++ b/src/applications/meta/panel/PhabricatorApplicationConfigurationPanel.php
@@ -27,7 +27,7 @@
   /**
    * Get the URI for this application configuration panel.
    *
-   * @param string? $path Optional path to append.
+   * @param string $path (optional) Path to append.
    * @return string Relative URI for the panel.
    */
   public function getPanelURI($path = '') {
diff --git a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
--- a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
+++ b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
@@ -456,8 +456,8 @@
    *
    * @param string  $thread_id Unique identifier, appropriate for use in a
    *                Message-ID, In-Reply-To or References headers.
-   * @param bool?   $is_first_message If true, indicates this is the first
-   *                message in the thread.
+   * @param bool    $is_first_message (optional) If true, indicates this is the
+   *                first message in the thread.
    * @return this
    */
   public function setThreadID($thread_id, $is_first_message = false) {
diff --git a/src/applications/repository/daemon/PhabricatorRepositoryPullLocalDaemon.php b/src/applications/repository/daemon/PhabricatorRepositoryPullLocalDaemon.php
--- a/src/applications/repository/daemon/PhabricatorRepositoryPullLocalDaemon.php
+++ b/src/applications/repository/daemon/PhabricatorRepositoryPullLocalDaemon.php
@@ -341,8 +341,8 @@
    * With the `$consume` flag, an internal cursor will also be incremented so
    * that these messages are not returned by subsequent calls.
    *
-   * @param bool? $consume Pass `true` to consume these messages, so the
-   *   process will not see them again.
+   * @param bool $consume (optional) Pass `true` to consume these messages, so
+   *   the process will not see them again.
    * @return list<wild> Pending update messages.
    *
    * @task pull
diff --git a/src/applications/repository/graphcache/PhabricatorRepositoryGraphCache.php b/src/applications/repository/graphcache/PhabricatorRepositoryGraphCache.php
--- a/src/applications/repository/graphcache/PhabricatorRepositoryGraphCache.php
+++ b/src/applications/repository/graphcache/PhabricatorRepositoryGraphCache.php
@@ -236,8 +236,8 @@
    * to force a cache update by passing the existing data to `$rebuild_data`.
    *
    * @param   int    $bucket_key Bucket key, from @{method:getBucketKey}.
-   * @param   mixed? $rebuild_data Current data, to force a cache rebuild of
-   *                 this bucket.
+   * @param   mixed  $rebuild_data (optional) Current data, to force a cache
+   *                 rebuild of this bucket.
    * @return  array  Data from the cache.
    * @task cache
    */
diff --git a/src/applications/repository/storage/PhabricatorRepository.php b/src/applications/repository/storage/PhabricatorRepository.php
--- a/src/applications/repository/storage/PhabricatorRepository.php
+++ b/src/applications/repository/storage/PhabricatorRepository.php
@@ -1701,7 +1701,8 @@
    * 2037). We adjust the pull frequency based on when the most recent commit
    * occurred.
    *
-   * @param   int? $minimum The minimum update interval to use, in seconds.
+   * @param   int  $minimum (optional) The minimum update interval to use, in
+   *   seconds.
    * @return  int   Repository update interval, in seconds.
    */
   public function loadUpdateInterval($minimum = 15) {
@@ -2169,7 +2170,8 @@
    * For lower-level service resolution, see @{method:getAlmanacServiceURI}.
    *
    * @param PhabricatorUser $viewer Viewing user.
-   * @param bool? $never_proxy `true` to throw if a client would be returned.
+   * @param bool $never_proxy (optional) `true` to throw if a client would be
+   *   returned.
    * @return ConduitClient|null Client, or `null` for local repositories.
    */
   public function newConduitClient(
diff --git a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
--- a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
+++ b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
@@ -732,7 +732,7 @@
    *
    * @param AphrontRequest  $request Request to read user PHIDs from.
    * @param string          $key Key to read in the request.
-   * @param list<const>?    $allow_types Other permitted PHID types.
+   * @param list<const>     $allow_types (optional) Other permitted PHID types.
    * @return list<phid>     List of user PHIDs and selector functions.
    * @task read
    */
@@ -807,7 +807,7 @@
    *
    * @param AphrontRequest  $request Request to read PHIDs from.
    * @param string          $key Key to read in the request.
-   * @param list<const>?    $allow_types Optional, list of permitted PHID
+   * @param list<const>     $allow_types (optional) List of permitted PHID
    *                        types.
    * @return list<phid>     List of object PHIDs.
    *
diff --git a/src/applications/settings/panel/PhabricatorSettingsPanel.php b/src/applications/settings/panel/PhabricatorSettingsPanel.php
--- a/src/applications/settings/panel/PhabricatorSettingsPanel.php
+++ b/src/applications/settings/panel/PhabricatorSettingsPanel.php
@@ -234,7 +234,7 @@
   /**
    * Get the URI for this panel.
    *
-   * @param string? $path Optional path to append.
+   * @param string $path (optional) Path to append.
    * @return string Relative URI for the panel.
    * @task panel
    */
diff --git a/src/applications/transactions/editengine/PhabricatorEditEngine.php b/src/applications/transactions/editengine/PhabricatorEditEngine.php
--- a/src/applications/transactions/editengine/PhabricatorEditEngine.php
+++ b/src/applications/transactions/editengine/PhabricatorEditEngine.php
@@ -713,8 +713,8 @@
    * to make Conduit a little easier to use.
    *
    * @param wild $identifier ID, PHID, or monogram.
-   * @param list<const>? $capabilities List of required capability constants,
-   *   or omit for defaults.
+   * @param list<const> $capabilities (optional) List of required capability
+   *   constants, or omit for defaults.
    * @return object Corresponding editable object.
    * @task load
    */
@@ -793,8 +793,8 @@
    * Load an object by ID.
    *
    * @param int $id Object ID.
-   * @param list<const>? $capabilities List of required capability constants,
-   *   or omit for defaults.
+   * @param list<const> $capabilities (optional) List of required capability
+   *   constants, or omit for defaults.
    * @return object|null Object, or null if no such object exists.
    * @task load
    */
@@ -810,8 +810,8 @@
    * Load an object by PHID.
    *
    * @param phid $phid Object PHID.
-   * @param list<const>? $capabilities List of required capability constants,
-   *   or omit for defaults.
+   * @param list<const> $capabilities (optional) List of required capability
+   *   constants, or omit for defaults.
    * @return object|null Object, or null if no such object exists.
    * @task load
    */
@@ -827,8 +827,8 @@
    * Load an object given a configured query.
    *
    * @param PhabricatorPolicyAwareQuery $query Configured query.
-   * @param list<const>? $capabilities List of required capability constants,
-   *  or omit for defaults.
+   * @param list<const> $capabilities (optional) List of required capability
+   *  constants, or omit for defaults.
    * @return object|null Object, or null if no such object exists.
    * @task load
    */
diff --git a/src/infrastructure/cache/PhutilKeyValueCache.php b/src/infrastructure/cache/PhutilKeyValueCache.php
--- a/src/infrastructure/cache/PhutilKeyValueCache.php
+++ b/src/infrastructure/cache/PhutilKeyValueCache.php
@@ -31,7 +31,7 @@
    * once.
    *
    * @param   string  $key Key to retrieve.
-   * @param   wild?   $default Optional value to return if the key is not
+   * @param   wild    $default (optional) Value to return if the key is not
    *                  found. By default, returns null.
    * @return  wild    Cache value (on cache hit) or default value (on cache
    *                  miss).
@@ -51,7 +51,7 @@
    *
    * @param   string    $key Key to set.
    * @param   wild      $value Value to set.
-   * @param   int|null? $ttl Optional TTL.
+   * @param   int|null  $ttl (optional) TTL.
    * @return  this
    * @task kvimpl
    */
@@ -93,7 +93,7 @@
    * policy and data will persist in cache indefinitely.
    *
    * @param dict<string, wild>  $keys Map of cache keys to values.
-   * @param int|null?           $ttl TTL for cache keys, in seconds.
+   * @param int|null            $ttl (optional) TTL for cache keys, in seconds.
    * @return this
    * @task kvimpl
    */
diff --git a/src/infrastructure/contentsource/PhabricatorContentSource.php b/src/infrastructure/contentsource/PhabricatorContentSource.php
--- a/src/infrastructure/contentsource/PhabricatorContentSource.php
+++ b/src/infrastructure/contentsource/PhabricatorContentSource.php
@@ -23,9 +23,9 @@
    * Construct a new content source object.
    *
    * @param const $source The source type constant to build a source for.
-   * @param array? $params Source parameters.
-   * @param bool? $force True to suppress errors and force construction of a
-   *   source even if the source type is not valid.
+   * @param array $params (optional) Source parameters.
+   * @param bool  $force (optional) True to suppress errors and force
+   *   construction of a source even if the source type is not valid.
    * @return PhabricatorContentSource New source object.
    */
   final public static function newForSource(
diff --git a/src/infrastructure/daemon/PhutilDaemonHandle.php b/src/infrastructure/daemon/PhutilDaemonHandle.php
--- a/src/infrastructure/daemon/PhutilDaemonHandle.php
+++ b/src/infrastructure/daemon/PhutilDaemonHandle.php
@@ -329,7 +329,7 @@
    * Dispatch an event to event listeners.
    *
    * @param  string $type Event type.
-   * @param  dict?  $params Event parameters.
+   * @param  dict   $params (optional) Event parameters.
    * @return void
    */
   private function dispatchEvent($type, array $params = array()) {
diff --git a/src/infrastructure/daemon/workers/PhabricatorWorker.php b/src/infrastructure/daemon/workers/PhabricatorWorker.php
--- a/src/infrastructure/daemon/workers/PhabricatorWorker.php
+++ b/src/infrastructure/daemon/workers/PhabricatorWorker.php
@@ -232,7 +232,7 @@
    *
    * @param string    $class Task class to queue.
    * @param array     $data Data for the followup task.
-   * @param array?    $options Options for the followup task.
+   * @param array     $options (optional) Options for the followup task.
    * @return this
    */
   final protected function queueTask(
@@ -261,7 +261,7 @@
    * this method to force the queue to flush before failing (for example, if
    * you are using queues to improve locking behavior).
    *
-   * @param map<string, wild>? $defaults Optional default options.
+   * @param map<string, wild> $defaults (optional) Default options.
    */
   final public function flushTaskQueue($defaults = array()) {
     foreach ($this->getQueuedTasks() as $task) {
diff --git a/src/infrastructure/edges/editor/PhabricatorEdgeEditor.php b/src/infrastructure/edges/editor/PhabricatorEdgeEditor.php
--- a/src/infrastructure/edges/editor/PhabricatorEdgeEditor.php
+++ b/src/infrastructure/edges/editor/PhabricatorEdgeEditor.php
@@ -48,7 +48,7 @@
    * @param phid  $src Source object PHID.
    * @param const $type Edge type constant.
    * @param phid  $dst Destination object PHID.
-   * @param map?  $options Options map (see documentation).
+   * @param map   $options (optional) Options map (see documentation).
    * @return this
    *
    * @task edit
diff --git a/src/infrastructure/edges/query/PhabricatorEdgeQuery.php b/src/infrastructure/edges/query/PhabricatorEdgeQuery.php
--- a/src/infrastructure/edges/query/PhabricatorEdgeQuery.php
+++ b/src/infrastructure/edges/query/PhabricatorEdgeQuery.php
@@ -256,8 +256,10 @@
    *     $object->attachHandles(array_select_keys($handles, $dst_phids));
    *   }
    *
-   * @param list? $src_phids List of PHIDs to select, or empty to select all.
-   * @param list? $types List of edge types to select, or empty to select all.
+   * @param list $src_phids (optional) List of PHIDs to select, or empty to
+   *   select all.
+   * @param list $types (optional) List of edge types to select, or empty to
+   *   select all.
    * @return list<phid> List of matching destination PHIDs.
    */
   public function getDestinationPHIDs(
diff --git a/src/infrastructure/markup/PhabricatorMarkupEngine.php b/src/infrastructure/markup/PhabricatorMarkupEngine.php
--- a/src/infrastructure/markup/PhabricatorMarkupEngine.php
+++ b/src/infrastructure/markup/PhabricatorMarkupEngine.php
@@ -59,8 +59,8 @@
    * @param PhabricatorMarkupInterface  $object The object to render.
    * @param string                      $field The field to render.
    * @param PhabricatorUser             $viewer User viewing the markup.
-   * @param object?                     $context_object A context object for
-   *                                    policy checks.
+   * @param object                      $context_object (optional) A context
+   *                                    object for policy checks.
    * @return string                     Marked up output.
    * @task markup
    */
@@ -196,7 +196,7 @@
    * @param string                      $field The field to retrieve.
    * @param string                      $metadata_key The engine metadata field
    *                                    to retrieve.
-   * @param wild?                       $default Optional default value.
+   * @param wild                        $default (optional) Default value.
    * @task markup
    */
   public function getEngineMetadata(
diff --git a/src/infrastructure/markup/PhutilMarkupEngine.php b/src/infrastructure/markup/PhutilMarkupEngine.php
--- a/src/infrastructure/markup/PhutilMarkupEngine.php
+++ b/src/infrastructure/markup/PhutilMarkupEngine.php
@@ -22,8 +22,8 @@
    * metadata may be available in your configuration.
    *
    * @param   string  $key Key to retrieve from metadata.
-   * @param   mixed?  $default Default value to return if the key is not
-   *   available.
+   * @param   mixed  $default (optional) Default value to return if the key is
+   *   not available.
    * @return  mixed   Metadata property, or default value.
    */
   abstract public function getTextMetadata($key, $default = null);
diff --git a/src/infrastructure/markup/markuprule/PhutilRemarkupRule.php b/src/infrastructure/markup/markuprule/PhutilRemarkupRule.php
--- a/src/infrastructure/markup/markuprule/PhutilRemarkupRule.php
+++ b/src/infrastructure/markup/markuprule/PhutilRemarkupRule.php
@@ -62,7 +62,7 @@
    *
    * @param   string              $name Tag name.
    * @param   dict<string, wild>  $attrs Tag attributes.
-   * @param   wild?               $content Tag content.
+   * @param   wild                $content (optional) Tag content.
    * @return  PhutilSafeHTML      Tag object.
    */
   protected function newTag($name, array $attrs, $content = null) {
diff --git a/src/infrastructure/markup/render.php b/src/infrastructure/markup/render.php
--- a/src/infrastructure/markup/render.php
+++ b/src/infrastructure/markup/render.php
@@ -17,8 +17,8 @@
  * parameters.
  *
  * @param string $tag The name of the tag, like `a` or `div`.
- * @param map<string, string>? $attributes A map of tag attributes.
- * @param wild? $content Content to put in the tag.
+ * @param map<string, string> $attributes (optional) A map of tag attributes.
+ * @param wild $content (optional) Content to put in the tag.
  * @return PhutilSafeHTML Tag object.
  */
 function phutil_tag($tag, array $attributes = array(), $content = null) {
diff --git a/src/infrastructure/storage/lisk/LiskDAO.php b/src/infrastructure/storage/lisk/LiskDAO.php
--- a/src/infrastructure/storage/lisk/LiskDAO.php
+++ b/src/infrastructure/storage/lisk/LiskDAO.php
@@ -264,7 +264,7 @@
    *
    * @param mode $mode Connection mode.
    * @param AphrontDatabaseConnection $connection Connection to cache.
-   * @param bool? $force_unique
+   * @param bool $force_unique (optional)
    * @return this
    * @task conn
    */
@@ -802,8 +802,9 @@
    * Get or build the database connection for this object.
    *
    * @param  string $mode 'r' for read, 'w' for read/write.
-   * @param  bool? $force_new True to force a new connection. The connection
-   *   will not be retrieved from or saved into the connection cache.
+   * @param  bool $force_new (optional) True to force a new connection. The
+   *   connection will not be retrieved from or saved into the connection
+   *   cache.
    * @return AphrontDatabaseConnection   Lisk connection object.
    *
    * @task   info
diff --git a/src/infrastructure/util/PhabricatorHash.php b/src/infrastructure/util/PhabricatorHash.php
--- a/src/infrastructure/util/PhabricatorHash.php
+++ b/src/infrastructure/util/PhabricatorHash.php
@@ -12,7 +12,7 @@
    * weak. Callers should prefer @{method:digestWithNamedKey}.
    *
    * @param   string  $string Input string.
-   * @param   string? $key
+   * @param   string  $key (optional)
    * @return  string  32-byte hexadecimal SHA1+HMAC hash.
    */
   public static function weakDigest($string, $key = null) {
diff --git a/src/view/phui/PHUICrumbsView.php b/src/view/phui/PHUICrumbsView.php
--- a/src/view/phui/PHUICrumbsView.php
+++ b/src/view/phui/PHUICrumbsView.php
@@ -16,7 +16,7 @@
    * a link.
    *
    * @param string  $text Text of the crumb.
-   * @param string? $href Optional href for the crumb.
+   * @param string $href (optional) href for the crumb.
    * @return this
    */
   public function addTextCrumb($text, $href = null) {
diff --git a/support/startup/PhabricatorStartup.php b/support/startup/PhabricatorStartup.php
--- a/support/startup/PhabricatorStartup.php
+++ b/support/startup/PhabricatorStartup.php
@@ -344,10 +344,10 @@
    * Fatal the request completely, sending a plain text message to the client.
    *
    * @param   string  $message Plain text message to send to the client.
-   * @param   string? $log_message Plain text message to send to the error log.
-   *                  If not provided, the client message is used. You can pass
-   *                  a more detailed message here (e.g., with stack traces) to
-   *                  avoid showing it to users.
+   * @param   string  $log_message (optional) Plain text message to send to the
+   *                  error log. If not provided, the client message is used.
+   *                  You can pass a more detailed message here (e.g., with
+   *                  stack traces) to avoid showing it to users.
    * @return  exit    This method **does not return**.
    *
    * @task apocalypse
diff --git a/support/startup/preamble-utils.php b/support/startup/preamble-utils.php
--- a/support/startup/preamble-utils.php
+++ b/support/startup/preamble-utils.php
@@ -4,7 +4,7 @@
  * Parse the "X_FORWARDED_FOR" HTTP header to determine the original client
  * address.
  *
- * @param  int? $layers Number of devices to trust.
+ * @param  int $layers (optional) Number of devices to trust.
  * @return void
  */
 function preamble_trust_x_forwarded_for_header($layers = 1) {