diff --git a/repos/libports/run/acpi_suspend.run b/repos/libports/run/acpi_suspend.run
index ee644a4e94..923d90c298 100644
--- a/repos/libports/run/acpi_suspend.run
+++ b/repos/libports/run/acpi_suspend.run
@@ -17,15 +17,8 @@
 #
 #  Thereby, by default serial output is disabled by this script for non Qemu.
 
-assert_spec x86
-
-if {
-	![have_spec hw] &&
-	![have_spec nova]
-} {
-	puts "Platform is unsupported."
-	exit 0
-}
+assert {[have_spec x86]}
+assert {[have_spec hw] || [have_spec nova]}
 
 
 if {[have_spec nova]} {
diff --git a/repos/libports/run/acpica.run b/repos/libports/run/acpica.run
index 2997dcbc05..01b5efe4d8 100644
--- a/repos/libports/run/acpica.run
+++ b/repos/libports/run/acpica.run
@@ -1,11 +1,4 @@
-if {
-	![have_spec hw] &&
-	![have_spec nova] &&
-	![have_spec sel4]
-} {
-	puts "Platform is unsupported."
-	exit 0
-}
+assert {[have_spec hw] || [have_spec nova] || [have_spec sel4]}
 
 set build_components {
 	core init timer
diff --git a/repos/libports/run/extract.run b/repos/libports/run/extract.run
index 761955c307..254150196d 100644
--- a/repos/libports/run/extract.run
+++ b/repos/libports/run/extract.run
@@ -1,10 +1,10 @@
-create_boot_directory
-
-if {[get_cmd_switch --autopilot] && [have_board virt_qemu_riscv]} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+if {[have_cmd_arg --autopilot]} {
+       assert {![have_board virt_qemu_riscv]} \
+               "Autopilot mode is not supported on this platform."
 }
 
+create_boot_directory
+
 import_from_depot [depot_user]/src/[base_src] \
                   [depot_user]/src/init
 
diff --git a/repos/libports/run/fatfs_blkio.run b/repos/libports/run/fatfs_blkio.run
index 98cd95d734..01a6c47c02 100644
--- a/repos/libports/run/fatfs_blkio.run
+++ b/repos/libports/run/fatfs_blkio.run
@@ -1,7 +1,4 @@
-if {[expr ![have_include "power_on/qemu"] && ![have_spec linux]]} {
-	puts "Test only runs in Qemu or Linux.\n";
-	exit 0
-}
+assert {[have_include power_on/qemu] || [have_spec linux]}
 
 create_boot_directory
 
diff --git a/repos/libports/run/fetchurl.inc b/repos/libports/run/fetchurl.inc
index a94606727c..476fe27df2 100644
--- a/repos/libports/run/fetchurl.inc
+++ b/repos/libports/run/fetchurl.inc
@@ -4,15 +4,16 @@
 # \date   2016-06-05
 #
 
-if {[have_board rpi3] || [have_board imx53_qsb_tz] || [have_board rpi]} {
-	puts "Run script does not support this platform."
-	exit 0
-}
+assert {![have_board rpi3]}
+assert {![have_board imx53_qsb_tz]}
+assert {![have_board rpi]}
 
-if {[get_cmd_switch --autopilot] && ([have_board linux] ||
-                                     [have_board virt_qemu_riscv])} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+assert {[have_recipe pkg/[drivers_nic_pkg]]} \
+	"Recipe for 'pkg/[drivers_nic_pkg]' not available."
+
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_board linux] && ![have_board virt_qemu_riscv]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 #
diff --git a/repos/libports/run/ieee754.run b/repos/libports/run/ieee754.run
index 2a4bdfb5c2..08d33a0f6f 100644
--- a/repos/libports/run/ieee754.run
+++ b/repos/libports/run/ieee754.run
@@ -1,10 +1,8 @@
-#
-# Raspberry PI 1 needs "undef exc" handling emulation code in the kernel
-# for ieee754 full-compliant support
-#
-if {[have_board rpi]} {
-	puts "Run script does not support Raspberry Pi 1"
-	exit 0
+assert {![have_board rpi]} {
+	Run script is not supported on this platform.
+
+	Raspberry PI 1 needs "undef exc" handling emulation code in the kernel
+	for ieee754 full-compliant support
 }
 
 build { core init lib/ld test/ieee754 lib/posix lib/libc lib/libm lib/vfs }
diff --git a/repos/libports/run/libc_block.run b/repos/libports/run/libc_block.run
index 83f04119e0..934bb8d36e 100644
--- a/repos/libports/run/libc_block.run
+++ b/repos/libports/run/libc_block.run
@@ -1,7 +1,4 @@
-if {[expr ![have_include "power_on/qemu"] && ![have_spec linux]]} {
-	puts "Test only supports Qemu or Linux.\n";
-	exit 0
-}
+assert {[have_include power_on/qemu] || [have_spec linux]}
 
 create_boot_directory
 
diff --git a/repos/libports/run/libc_getaddrinfo.run b/repos/libports/run/libc_getaddrinfo.run
index 9ae9acca3d..e41e28c9d5 100644
--- a/repos/libports/run/libc_getaddrinfo.run
+++ b/repos/libports/run/libc_getaddrinfo.run
@@ -1,7 +1,5 @@
-if {[have_spec linux]} {
-	puts "The [run_name] scenario requires QEMU networking."
-	exit 1
-}
+assert {[have_include power_on/qemu]} \
+	"Run script requires QEMU networking"
 
 create_boot_directory
 
diff --git a/repos/libports/run/libc_integration.run b/repos/libports/run/libc_integration.run
index 547bc02b39..2f15504ca3 100644
--- a/repos/libports/run/libc_integration.run
+++ b/repos/libports/run/libc_integration.run
@@ -10,17 +10,14 @@ set config_ds 1024
 
 set run_script_timeout 500000
 
-if { [get_cmd_switch --autopilot] } {
+if {[have_cmd_arg --autopilot]} {
 	set current_date [clock format [clock seconds] -format %a]
-	if {[get_cmd_switch --autopilot] && $current_date != "Sat" && $current_date != "Sun" } {
-		puts "\n Run script is not supported on this platform today. \n";
-		exit 0
+	assert {$current_date == "Sat" || $current_date == "Sun"} \
+		"Autopilot mode is not supported on this platform today."
 	}
 
-	if {[have_include "power_on/qemu"]} {
-		puts "Run script does not support autopilot mode on Qemu"
-		exit 0
-	}
+	assert {![have_include power_on/qemu]} \
+		"Autopilot mode is not supported on this platform."
 
 	set run 0
 	set run_script_timeout 1200
@@ -38,10 +35,7 @@ if { [get_cmd_switch --autopilot] } {
 		set run 1
 	}
 
-	if {!$run} {
-		puts "\n Run script is not supported on this platform. \n";
-		exit 0
-	}
+	assert {$run} "Autopilot mode is not supported on this platform."
 }
 
 create_boot_directory
diff --git a/repos/libports/run/libc_vfs_filesystem_test.inc b/repos/libports/run/libc_vfs_filesystem_test.inc
index 89c90cff02..9432627002 100644
--- a/repos/libports/run/libc_vfs_filesystem_test.inc
+++ b/repos/libports/run/libc_vfs_filesystem_test.inc
@@ -13,14 +13,11 @@
 # \arg test_vfs_config
 #
 
+assert {[have_include power_on/qemu] || [have_spec linux]}
+
 if {[catch { exec which $mkfs_cmd } ]} {
 	puts stderr "Error: $mkfs_cmd not installed, aborting test"; exit }
 
-if {[expr ![have_include "power_on/qemu"] && ![have_spec linux]]} {
-	puts "Run script does not support this platform."
-	exit 0
-}
-
 #
 # Build
 #
diff --git a/repos/libports/run/libc_vfs_fs_fat.run b/repos/libports/run/libc_vfs_fs_fat.run
index aedd59744b..17dfc3a5f0 100644
--- a/repos/libports/run/libc_vfs_fs_fat.run
+++ b/repos/libports/run/libc_vfs_fs_fat.run
@@ -1,6 +1,6 @@
-if {[get_cmd_switch --autopilot] && [have_board virt_qemu_riscv]} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_board virt_qemu_riscv]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 set mkfs_cmd   [installed_command mkfs.vfat]
diff --git a/repos/libports/run/lwip.run b/repos/libports/run/lwip.run
index e65c485608..45a0b1e15b 100644
--- a/repos/libports/run/lwip.run
+++ b/repos/libports/run/lwip.run
@@ -17,15 +17,17 @@
 #       tun/tap proxy driver at os/src/driver/nic/linux)
 #
 
-if {[have_board linux] ||
-    [have_board imx53_qsb_tz] ||
-    [have_board rpi3] ||
-    [have_board rpi]} {
-	puts "\n Run script is not supported on this platform. \n"; exit 0 }
+assert {![have_board linux]}
+assert {![have_board imx53_qsb_tz]}
+assert {![have_board rpi3]}
+assert {![have_board rpi]}
 
-if {[get_cmd_switch --autopilot] && [have_board virt_qemu_riscv]} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+assert {[have_recipe pkg/[drivers_nic_pkg]]} \
+	"Recipe for 'pkg/[drivers_nic_pkg]' not available."
+
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_board virt_qemu_riscv]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 set lynx [installed_command lynx]
diff --git a/repos/libports/run/lwip_lx.run b/repos/libports/run/lwip_lx.run
index 45010c86a1..18ec1d3e8e 100644
--- a/repos/libports/run/lwip_lx.run
+++ b/repos/libports/run/lwip_lx.run
@@ -20,7 +20,7 @@
 #    ! sudo ip tuntap delete $TAP_DEV mode tap
 #
 
-assert_spec linux
+assert {[have_spec linux]}
 
 build {
 	core init timer lib/ld lib/libc lib/vfs lib/vfs_lwip
diff --git a/repos/libports/run/memcpy.run b/repos/libports/run/memcpy.run
index 92549772b6..2a96f689c7 100644
--- a/repos/libports/run/memcpy.run
+++ b/repos/libports/run/memcpy.run
@@ -1,8 +1,6 @@
-if { [get_cmd_switch --autopilot] } {
-	if {[have_include "power_on/qemu"]} {
-		puts "\nRun script does not support Qemu.\n"
-		exit 0
-	}
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_include power_on/qemu]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 build { core init lib/ld lib/libc lib/vfs test/memcpy }
diff --git a/repos/libports/run/nic_bridge.run b/repos/libports/run/nic_bridge.run
index d1cf388eb6..a754cdef7d 100644
--- a/repos/libports/run/nic_bridge.run
+++ b/repos/libports/run/nic_bridge.run
@@ -1,16 +1,9 @@
-if {![have_include power_on/qemu]} {
-	puts "Run script is only supported on Qemu"
-	exit 0
-}
+assert {[have_include power_on/qemu]}
+assert {![have_board rpi3]}
 
-if {[have_board rpi3]} {
-	puts "\n Run script is not supported on this platform. \n";
-	exit 0
-}
-
-if {[get_cmd_switch --autopilot] && [have_board virt_qemu_riscv]} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_board virt_qemu_riscv]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 create_boot_directory
diff --git a/repos/libports/run/nic_router.inc b/repos/libports/run/nic_router.inc
index cb66ff18c5..def6b3097e 100644
--- a/repos/libports/run/nic_router.inc
+++ b/repos/libports/run/nic_router.inc
@@ -1,6 +1,6 @@
-if {[get_cmd_switch --autopilot] && [have_board virt_qemu_riscv]} {
-	puts "Autopilot mode is not supported on this platform."
-	exit 0
+if {[have_cmd_arg --autopilot]} {
+	assert {![have_board virt_qemu_riscv]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 set targets {
diff --git a/repos/libports/run/nic_router_ipv4_fragm.run b/repos/libports/run/nic_router_ipv4_fragm.run
index 25c1070213..59d4406c63 100644
--- a/repos/libports/run/nic_router_ipv4_fragm.run
+++ b/repos/libports/run/nic_router_ipv4_fragm.run
@@ -22,10 +22,7 @@
 #    ! sudo ip tuntap delete tap0 mode tap
 #
 
-if {![have_board linux]} {
-	puts "Run script is not supported on this platform."
-	exit 0
-}
+assert {[have_board linux]}
 
 set nping  [installed_command nping]
 set setcap [installed_command setcap]
diff --git a/repos/libports/run/oss.run b/repos/libports/run/oss.run
index 0cd4571d58..2e8064abf5 100644
--- a/repos/libports/run/oss.run
+++ b/repos/libports/run/oss.run
@@ -1,14 +1,6 @@
-assert_spec x86
-
-if {[have_board linux]} {
-	puts "Run script does not support Linux."
-	exit 0
-}
-
-if {[have_include "power_on/qemu"]} {
-	puts "Run script does not support Qemu"
-	exit 0
-}
+assert {[have_spec x86]}
+assert {![have_board linux]}
+assert {![have_include power_on/qemu]}
 
 build {
 	core init timer lib/ld lib/libc lib/vfs lib/posix lib/vfs_legacy_oss
diff --git a/repos/libports/run/smartcard.run b/repos/libports/run/smartcard.run
index bc7da73361..a3edaba3d0 100644
--- a/repos/libports/run/smartcard.run
+++ b/repos/libports/run/smartcard.run
@@ -5,12 +5,9 @@
 #       configured for the application and for the USB driver.
 #
 
-if {[have_include "power_on/qemu"] || [have_spec linux]} {
-	puts "Run script does not support Qemu or Linux"
-	exit 0
-}
-
-assert_spec x86_64
+assert {[have_spec x86_64]}
+assert {![have_include power_on/qemu]}
+assert {![have_spec linux]}
 
 #
 # Please configure your reader's vendor and product IDs here
diff --git a/repos/libports/run/sntp_client.run b/repos/libports/run/sntp_client.run
index ff0b8b0771..46275f3d2a 100644
--- a/repos/libports/run/sntp_client.run
+++ b/repos/libports/run/sntp_client.run
@@ -1,8 +1,8 @@
-if { [get_cmd_switch --autopilot] } { assert_spec x86 }
+assert {![have_spec linux]}
 
-if { [have_spec linux] } {
-	puts "Run script is not supported on this platform."
-	exit 0
+if {[have_cmd_arg --autopilot]} {
+	assert {[have_spec x86]} \
+		"Autopilot mode is not supported on this platform."
 }
 
 create_boot_directory
diff --git a/repos/libports/run/system_rtc.run b/repos/libports/run/system_rtc.run
index 3531217540..037216b155 100644
--- a/repos/libports/run/system_rtc.run
+++ b/repos/libports/run/system_rtc.run
@@ -1,9 +1,5 @@
-assert_spec x86
-
-if {[expr ![have_include power_on/qemu] && ![have_spec linux]]} {
-	puts "Test requires Qemu or Linux."
-	exit 0
-}
+assert {[have_spec x86]}
+assert {[have_include power_on/qemu] || [have_spec linux]}
 
 create_boot_directory