diff --git a/.github/actions/prepare-test/action.yml b/.github/actions/prepare-test/action.yml
index f93d102116..a6134cc706 100644
--- a/.github/actions/prepare-test/action.yml
+++ b/.github/actions/prepare-test/action.yml
@@ -23,15 +23,27 @@ runs:
       shell: bash
       run: |
         set -e # Fail this Action if `gh release list` fails.
+
+        if [[ "$RUNNER_OS" == "Linux" ]]; then
+          artifact_name="codeql-bundle-linux64.tar.gz"
+        elif [[ "$RUNNER_OS" == "macOS" ]]; then
+          artifact_name="codeql-bundle-osx64.tar.gz"
+        elif [[ "$RUNNER_OS" == "Windows" ]]; then
+          artifact_name="codeql-bundle-win64.tar.gz"
+        else
+          echo "::error::Unrecognized OS $RUNNER_OS"
+          exit 1
+        fi
+
         if [[ ${{ inputs.version }} == "nightly-latest" ]]; then
-          export LATEST=`gh release list --repo dsp-testing/codeql-cli-nightlies -L 1 | cut -f 3`
-          echo "tools-url=https://github.com/dsp-testing/codeql-cli-nightlies/releases/download/$LATEST/codeql-bundle.tar.gz" >> $GITHUB_OUTPUT
+          tag=`gh release list --repo dsp-testing/codeql-cli-nightlies -L 1 | cut -f 3`
+          echo "tools-url=https://github.com/dsp-testing/codeql-cli-nightlies/releases/download/$tag/$artifact_name" >> $GITHUB_OUTPUT
         elif [[ ${{ inputs.version }} == *"nightly"* ]]; then
-          export VERSION=`echo ${{ inputs.version }} | sed -e 's/^.*\-//'`
-          echo "tools-url=https://github.com/dsp-testing/codeql-cli-nightlies/releases/download/codeql-bundle-$VERSION-manual/codeql-bundle.tar.gz" >> $GITHUB_OUTPUT
+          version=`echo ${{ inputs.version }} | sed -e 's/^.*\-//'`
+          echo "tools-url=https://github.com/dsp-testing/codeql-cli-nightlies/releases/download/codeql-bundle-$version-manual/$artifact_name" >> $GITHUB_OUTPUT
         elif [[ ${{ inputs.version }} == *"stable"* ]]; then
-          export VERSION=`echo ${{ inputs.version }} | sed -e 's/^.*\-//'`
-          echo "tools-url=https://github.com/github/codeql-action/releases/download/codeql-bundle-$VERSION/codeql-bundle.tar.gz" >> $GITHUB_OUTPUT
+          version=`echo ${{ inputs.version }} | sed -e 's/^.*\-//'`
+          echo "tools-url=https://github.com/github/codeql-action/releases/download/codeql-bundle-$version/$artifact_name" >> $GITHUB_OUTPUT
         elif [[ ${{ inputs.version }} == "latest" ]]; then
           echo "tools-url=latest" >> $GITHUB_OUTPUT
         elif [[ ${{ inputs.version }} == "cached" ]]; then