diff --git a/src/Pure/Admin/build_vampire.scala b/src/Pure/Admin/build_vampire.scala
--- a/src/Pure/Admin/build_vampire.scala
+++ b/src/Pure/Admin/build_vampire.scala
@@ -1,166 +1,166 @@
 /*  Title:      Pure/Admin/build_vampire.scala
     Author:     Makarius
 
 Build Isabelle Vampire component from official download.
 */
 
 package isabelle
 
 
 object Build_Vampire
 {
   val default_download_url = "https://github.com/vprover/vampire/archive/refs/tags/v4.6.tar.gz"
   val default_jobs = 1
 
   def make_component_name(version: String): String =
     "vampire-" + Library.try_unprefix("v", version).getOrElse(version)
 
 
   /* build Vampire */
 
   def build_vampire(
     download_url: String = default_download_url,
     jobs: Int = default_jobs,
     component_name: String = "",
     verbose: Boolean = false,
     progress: Progress = new Progress,
     target_dir: Path = Path.current): Unit =
   {
     Isabelle_System.require_command("cmake")
 
     Isabelle_System.with_tmp_dir("build")(tmp_dir =>
     {
       /* component */
 
       val Archive_Name = """^.*?([^/]+)$""".r
       val Version = """^v?([0-9.]+)\.tar.gz$""".r
 
       val archive_name =
         download_url match {
           case Archive_Name(name) => name
           case _ => error("Failed to determine source archive name from " + quote(download_url))
         }
 
       val version =
         archive_name match {
           case Version(version) => version
           case _ => error("Failed to determine component version from " + quote(archive_name))
         }
 
       val component = proper_string(component_name) getOrElse make_component_name(version)
       val component_dir = Isabelle_System.new_directory(target_dir + Path.basic(component))
       progress.echo("Component " + component_dir)
 
 
       /* platform */
 
       val platform_name =
         proper_string(Isabelle_System.getenv("ISABELLE_PLATFORM64")) getOrElse
           error("No 64bit platform")
 
       val platform_dir = Isabelle_System.make_directory(component_dir + Path.basic(platform_name))
 
 
       /* download source */
 
       val archive_path = tmp_dir + Path.basic(archive_name)
       Isabelle_System.download_file(download_url, archive_path, progress = progress)
 
       Isabelle_System.bash("tar xzf " + File.bash_path(archive_path), cwd = tmp_dir.file).check
       val source_name = File.get_dir(tmp_dir)
 
       Isabelle_System.bash(
         "tar xzf " + archive_path + " && mv " + Bash.string(source_name) + " src",
         cwd = component_dir.file).check
 
 
       /* build */
 
       progress.echo("Building Vampire for " + platform_name + " ...")
 
       val build_dir = tmp_dir + Path.basic(source_name)
       Isabelle_System.copy_file(build_dir + Path.explode("LICENCE"), component_dir)
 
       val cmake_opts = if (Platform.is_linux) "-DBUILD_SHARED_LIBS=0 " else ""
       val cmake_out =
         progress.bash("cmake " + cmake_opts + """-G "Unix Makefiles" .""",
           cwd = build_dir.file, echo = verbose).check.out
 
       val Pattern = """-- Setting binary name to '?([^\s']*)'?""".r
       val binary =
         split_lines(cmake_out).collectFirst({ case Pattern(name) => name })
           .getOrElse(error("Failed to determine binary name from cmake output:\n" + cmake_out))
 
       progress.bash("make -j" + jobs, cwd = build_dir.file, echo = verbose).check
 
       Isabelle_System.copy_file(build_dir + Path.basic("bin") + Path.basic(binary).platform_exe,
         platform_dir + Path.basic("vampire").platform_exe)
 
 
       /* settings */
 
       val etc_dir = Isabelle_System.make_directory(component_dir + Path.basic("etc"))
       File.write(etc_dir + Path.basic("settings"),
         """# -*- shell-script -*- :mode=shellscript:
 
 VAMPIRE_HOME="$COMPONENT/$ISABELLE_PLATFORM64"
 
 ISABELLE_VAMPIRE="$VAMPIRE_HOME/vampire"
 """)
 
 
       /* README */
 
       File.write(component_dir + Path.basic("README"),
         "This Isabelle component provides Vampire " + version + """using the
 original sources from """.stripMargin + download_url + """
 
 The executables have been built via "cmake . && make"
 
 
         Makarius
         """ + Date.Format.date(Date.now()) + "\n")
     })
   }
 
 
   /* Isabelle tool wrapper */
 
   val isabelle_tool =
-    Isabelle_Tool("build_vampire", "build prover component from repository", Scala_Project.here,
-    args =>
+    Isabelle_Tool("build_vampire", "build prover component from official download",
+    Scala_Project.here, args =>
     {
       var target_dir = Path.current
       var download_url = default_download_url
       var jobs = default_jobs
       var component_name = ""
       var verbose = false
 
       val getopts = Getopts("""
 Usage: isabelle build_vampire [OPTIONS]
 
   Options are:
     -D DIR       target directory (default ".")
     -U URL       download URL
                  (default: """" + default_download_url + """")
     -j NUMBER    parallel jobs for make (default: """ + default_jobs + """)
     -n NAME      component name (default: """" + make_component_name("VERSION") + """")
     -v           verbose
 
   Build prover component from official download.
 """,
         "D:" -> (arg => target_dir = Path.explode(arg)),
         "U:" -> (arg => download_url = arg),
         "j:" -> (arg => jobs = Value.Nat.parse(arg)),
         "n:" -> (arg => component_name = arg),
         "v" -> (_ => verbose = true))
 
       val more_args = getopts(args)
       if (more_args.nonEmpty) getopts.usage()
 
       val progress = new Console_Progress()
 
       build_vampire(download_url = download_url, component_name = component_name,
         jobs = jobs, verbose = verbose, progress = progress, target_dir = target_dir)
     })
 }