--- a/taskcluster/ci/toolchain/windows.yml
+++ b/taskcluster/ci/toolchain/windows.yml
@@ -13,16 +13,17 @@ win32-clang-cl/opt:
     worker:
         implementation: generic-worker
         max-run-time: 36000
     run:
         using: toolchain-script
         script: build-clang32-windows.sh
         resources:
             - 'build/build-clang/**'
+            - 'build/src/taskcluster/scripts/misc/build-clang-windows-helper32.sh'
 
 win64-clang-cl/opt:
     description: "Clang-cl toolchain build"
     treeherder:
         kind: build
         platform: toolchains/opt
         symbol: TW64(clang-cl)
         tier: 2
@@ -30,16 +31,17 @@ win64-clang-cl/opt:
     worker:
         implementation: generic-worker
         max-run-time: 36000
     run:
         using: toolchain-script
         script: build-clang64-windows.sh
         resources:
             - 'build/build-clang/**'
+            - 'build/src/taskcluster/scripts/misc/build-clang-windows-helper64.sh'
 
 win32-clang-tidy/opt:
     description: "Clang-tidy toolchain build"
     index:
         product: static-analysis
         job-name: win32-clang-tidy
     treeherder:
         kind: build
@@ -50,16 +52,17 @@ win32-clang-tidy/opt:
     worker:
         implementation: generic-worker
         max-run-time: 36000
     run:
         using: toolchain-script
         script: build-clang-tidy32-windows.sh
         resources:
             - 'build/build-clang/**'
+            - 'build/src/taskcluster/scripts/misc/build-clang-windows-helper32.sh'
 
 win64-clang-tidy/opt:
     description: "Clang-tidy toolchain build"
     index:
         product: static-analysis
         job-name: win64-clang-tidy
     treeherder:
         kind: build
@@ -70,8 +73,9 @@ win64-clang-tidy/opt:
     worker:
         implementation: generic-worker
         max-run-time: 36000
     run:
         using: toolchain-script
         script: build-clang-tidy64-windows.sh
         resources:
             - 'build/build-clang/**'
+            - 'build/src/taskcluster/scripts/misc/build-clang-windows-helper64.sh'

--- a/taskcluster/scripts/misc/build-clang-windows-helper32.sh
+++ b/taskcluster/scripts/misc/build-clang-windows-helper32.sh
@@ -1,26 +1,25 @@
 #!/bin/bash
 
 set -x -e -v
 
 # This script is for building clang-cl on Windows.
 
-chmod +x build/src/python/mozbuild/mozbuild/action/tooltool.py
 : TOOLTOOL_CACHE                ${TOOLTOOL_CACHE:=/home/worker/tooltool-cache}
 export TOOLTOOL_CACHE
 
 TOOLTOOL_AUTH_FILE=/c/builds/relengapi.tok
 if [ ! -e ${TOOLTOOL_AUTH_FILE} ]; then
     echo cannot find ${TOOLTOOL_AUTH_FILE}
     exit 1
 fi
 
 TOOLTOOL_MANIFEST=build/src/browser/config/tooltool-manifests/win32/build-clang-cl.manifest
-./build/src/python/mozbuild/mozbuild/action/tooltool.py --authentication-file="${TOOLTOOL_AUTH_FILE}" -m "${TOOLTOOL_MANIFEST}" fetch
+./build/src/mach artifact toolchain -v --authentication-file="${TOOLTOOL_AUTH_FILE}" --tooltool-manifest "${TOOLTOOL_MANIFEST}"
 
 # Set up all the Visual Studio paths.
 MSVC_DIR=vs2015u3
 VSWINPATH="$(cd ${MSVC_DIR} && pwd)"
 
 echo vswinpath ${VSWINPATH}
 
 export WINDOWSSDKDIR="${VSWINPATH}/SDK"

--- a/taskcluster/scripts/misc/build-clang-windows-helper64.sh
+++ b/taskcluster/scripts/misc/build-clang-windows-helper64.sh
@@ -1,26 +1,25 @@
 #!/bin/bash
 
 set -x -e -v
 
 # This script is for building clang-cl on Windows.
 
-chmod +x build/src/python/mozbuild/mozbuild/action/tooltool.py
 : TOOLTOOL_CACHE                ${TOOLTOOL_CACHE:=/home/worker/tooltool-cache}
 export TOOLTOOL_CACHE
 
 TOOLTOOL_AUTH_FILE=/c/builds/relengapi.tok
 if [ ! -e ${TOOLTOOL_AUTH_FILE} ]; then
     echo cannot find ${TOOLTOOL_AUTH_FILE}
     exit 1
 fi
 
 TOOLTOOL_MANIFEST=build/src/browser/config/tooltool-manifests/win32/build-clang-cl.manifest
-./build/src/python/mozbuild/mozbuild/action/tooltool.py --authentication-file="${TOOLTOOL_AUTH_FILE}" -m "${TOOLTOOL_MANIFEST}" fetch
+./build/src/mach artifact toolchain -v --authentication-file="${TOOLTOOL_AUTH_FILE}" --tooltool-manifest "${TOOLTOOL_MANIFEST}"
 
 # Set up all the Visual Studio paths.
 MSVC_DIR=vs2015u3
 VSWINPATH="$(cd ${MSVC_DIR} && pwd)"
 
 echo vswinpath ${VSWINPATH}
 
 export WINDOWSSDKDIR="${VSWINPATH}/SDK"