diff --git a/scripts/symbols/import_project_symbols.php b/scripts/symbols/import_project_symbols.php
index 2f970182c2..d2946e8ef6 100755
--- a/scripts/symbols/import_project_symbols.php
+++ b/scripts/symbols/import_project_symbols.php
@@ -1,208 +1,205 @@
 #!/usr/bin/env php
 <?php
 
 
 $root = dirname(dirname(dirname(__FILE__)));
 require_once $root.'/scripts/__init_script__.php';
 
 $args = new PhutilArgumentParser($argv);
 $args->setSynopsis(<<<EOSYNOPSIS
 **import_project_symbols.php** [__options__] __project_name__ < symbols
 
   Import project symbols (symbols are read from stdin).
 EOSYNOPSIS
   );
 $args->parseStandardArguments();
 $args->parse(
   array(
     array(
       'name'      => 'no-purge',
       'help'      => 'Do not clear all symbols for this project before '.
                      'uploading new symbols. Useful for incremental updating.',
     ),
     array(
       'name'      => 'ignore-errors',
       'help'      => 'If a line can\'t be parsed, ignore that line and '.
                      'continue instead of exiting.',
     ),
     array(
       'name'      => 'max-transaction',
       'param'     => 'num-syms',
       'default'  => '100000',
       'help'      => 'Maximum number of symbols that should '.
                      'be part of a single transaction',
     ),
     array(
       'name'      => 'more',
       'wildcard'  => true,
     ),
   ));
 
 $more = $args->getArg('more');
 if (count($more) !== 1) {
   $args->printHelpAndExit();
 }
 
 $project_name = head($more);
 $project = id(new PhabricatorRepositoryArcanistProject())->loadOneWhere(
   'name = %s',
   $project_name);
 
 if (!$project) {
   // TODO: Provide a less silly way to do this explicitly, or just do it right
   // here.
   echo "Project '{$project_name}' is unknown. Upload a diff to implicitly ".
        "create it.\n";
   exit(1);
 }
 
 echo "Parsing input from stdin...\n";
 $input = file_get_contents('php://stdin');
 $input = trim($input);
 $input = explode("\n", $input);
 
 
 function commit_symbols ($syms, $project, $no_purge) {
   echo "Looking up path IDs...\n";
   $path_map =
     PhabricatorRepositoryCommitChangeParserWorker::lookupOrCreatePaths(
            ipull($syms, 'path'));
 
   $symbol = new PhabricatorRepositorySymbol();
   $conn_w = $symbol->establishConnection('w');
 
   echo "Preparing queries...\n";
   $sql = array();
   foreach ($syms as $dict) {
     $sql[] = qsprintf(
                       $conn_w,
                       '(%d, %s, %s, %s, %s, %d, %d)',
                       $project->getID(),
                       $dict['ctxt'],
                       $dict['name'],
                       $dict['type'],
                       $dict['lang'],
                       $dict['line'],
                       $path_map[$dict['path']]);
   }
 
   if (!$no_purge) {
     echo "Purging old syms...\n";
     queryfx($conn_w,
             'DELETE FROM %T WHERE arcanistProjectID = %d',
             $symbol->getTableName(),
             $project->getID());
   }
 
   echo "Loading ".number_format(count($sql))." syms...\n";
   foreach (array_chunk($sql, 128) as $chunk) {
     queryfx($conn_w,
             'INSERT INTO %T
       (arcanistProjectID, symbolContext, symbolName, symbolType,
         symbolLanguage, lineNumber, pathID) VALUES %Q',
             $symbol->getTableName(),
             implode(', ', $chunk));
   }
 
 }
 
+function check_string_value($value, $field_name, $line_no, $max_length) {
+   if (strlen($value) > $max_length) {
+      throw new Exception(
+        "{$field_name} '{$value}' defined on line #{$line_no} is too long, ".
+        "maximum {$field_name} length is {$max_length} characters.");
+    }
+
+    if (!phutil_is_utf8_with_only_bmp_characters($value)) {
+      throw new Exception(
+        "{$field_name} '{$value}' defined on line #{$line_no} is not a valid ".
+        "UTF-8 string, ".
+        "it should contain only UTF-8 characters.");
+    }
+}
+
 $no_purge = $args->getArg('no-purge');
 $symbols = array();
 foreach ($input as $key => $line) {
   try {
     $line_no = $key + 1;
     $matches = null;
     $ok = preg_match(
       '/^((?P<context>[^ ]+)? )?(?P<name>[^ ]+) (?P<type>[^ ]+) '.
       '(?P<lang>[^ ]+) (?P<line>\d+) (?P<path>.*)$/',
       $line,
       $matches);
     if (!$ok) {
       throw new Exception(
         "Line #{$line_no} of input is invalid. Expected five or six ".
         "space-delimited fields: maybe symbol context, symbol name, symbol ".
         "type, symbol language, line number, path. ".
         "For example:\n\n".
         "idx function php 13 /path/to/some/file.php\n\n".
         "Actual line was:\n\n".
         "{$line}");
     }
     if (empty($matches['context'])) {
       $matches['context'] = '';
     }
     $context     = $matches['context'];
     $name        = $matches['name'];
     $type        = $matches['type'];
     $lang        = $matches['lang'];
     $line_number = $matches['line'];
     $path        = $matches['path'];
 
-    if (strlen($context) > 128) {
-      throw new Exception(
-        "Symbol context '{$context}' defined on line #{$line_no} is too long, ".
-        "maximum symbol context length is 128 characters.");
-    }
-
-    if (strlen($name) > 128) {
-      throw new Exception(
-        "Symbol name '{$name}' defined on line #{$line_no} is too long, ".
-        "maximum symbol name length is 128 characters.");
-    }
-
-    if (strlen($type) > 12) {
-      throw new Exception(
-        "Symbol type '{$type}' defined on line #{$line_no} is too long, ".
-        "maximum symbol type length is 12 characters.");
-    }
-
-    if (strlen($lang) > 32) {
-      throw new Exception(
-        "Symbol language '{$lang}' defined on line #{$line_no} is too long, ".
-        "maximum symbol language length is 32 characters.");
-    }
+    check_string_value($context, 'Symbol context', $line_no, 128);
+    check_string_value($name, 'Symbol name', $line_no, 128);
+    check_string_value($type, 'Symbol type', $line_no, 12);
+    check_string_value($lang, 'Symbol language', $line_no, 32);
+    check_string_value($path, 'Path', $line_no, 512);
 
-    if (!strlen($path) || $path[0] != 0) {
+    if (!strlen($path) || $path[0] != '/') {
       throw new Exception(
         "Path '{$path}' defined on line #{$line_no} is invalid. Paths should ".
         "begin with '/' and specify a path from the root of the project, like ".
         "'/src/utils/utils.php'.");
     }
 
     $symbols[] = array(
       'ctxt' => $context,
       'name' => $name,
       'type' => $type,
       'lang' => $lang,
       'line' => $line_number,
       'path' => $path,
     );
   } catch (Exception $e) {
     if ($args->getArg('ignore-errors')) {
       continue;
     } else {
       throw $e;
     }
   }
 
   if (count ($symbols) >= $args->getArg('max-transaction')) {
       try {
         echo "Committing {$args->getArg('max-transaction')} symbols....\n";
         commit_symbols($symbols, $project, $no_purge);
         $no_purge = true;
         unset($symbols);
         $symbols = array();
       } catch (Exception $e) {
         if ($args->getArg('ignore-errors')) {
           continue;
         } else {
           throw $e;
         }
       }
   }
 }
 
 if (count($symbols)) {
   commit_symbols($symbols, $project, $no_purge);
 }
 
 echo "Done.\n";