diff --git a/build/dart/copy_tree.gni b/build/dart/copy_tree.gni
index 28054904812..49403919944 100644
--- a/build/dart/copy_tree.gni
+++ b/build/dart/copy_tree.gni
@@ -22,6 +22,8 @@ template("copy_tree") {
   source = invoker.source
   dest = invoker.dest
   action(target_name) {
+    mnemonic = "COPY_TREE"
+
     if (defined(invoker.visibility)) {
       visibility = invoker.visibility
     }
diff --git a/build/dart/dart_action.gni b/build/dart/dart_action.gni
index 70536b61ca3..6e754390a73 100644
--- a/build/dart/dart_action.gni
+++ b/build/dart/dart_action.gni
@@ -46,17 +46,15 @@ template("_compiled_action") {
   assert(defined(invoker.args), "args must be defined for $target_name")
 
   action(target_name) {
-    if (defined(invoker.visibility)) {
-      visibility = invoker.visibility
-    }
-
-    if (defined(invoker.testonly)) {
-      testonly = invoker.testonly
-    }
-
-    if (defined(invoker.pool)) {
-      pool = invoker.pool
-    }
+    forward_variables_from(invoker,
+                           [
+                             "depfile",
+                             "mnemonic",
+                             "outputs",
+                             "pool",
+                             "testonly",
+                             "visibility",
+                           ])
 
     script = "$_dart_root/build/gn_run_binary.py"
 
@@ -65,7 +63,6 @@ template("_compiled_action") {
     } else {
       inputs = []
     }
-    outputs = invoker.outputs
 
     # Construct the host toolchain version of the tool.
     host_tool = invoker.tool + "($host_toolchain)"
@@ -86,10 +83,6 @@ template("_compiled_action") {
       deps += invoker.deps
     }
 
-    if (defined(invoker.depfile)) {
-      depfile = invoker.depfile
-    }
-
     # The "compiled_action" argument to gn_run_binary.py indicates that
     # it will exit with a non-zero status when the target program does.
     args = [ "compiled_action" ]
@@ -125,6 +118,7 @@ template("_prebuilt_tool_action") {
                            [
                              "depfile",
                              "deps",
+                             "mnemonic",
                              "outputs",
                              "pool",
                              "testonly",
@@ -297,10 +291,11 @@ template("_built_tool_action") {
                              "deps",
                              "inputs",
                              "metadata",
+                             "mnemonic",
                              "outputs",
                              "pool",
-                             "tool",
                              "testonly",
+                             "tool",
                              "visibility",
                            ])
 
@@ -362,6 +357,7 @@ template("dart_action") {
                              "depfile",
                              "deps",
                              "inputs",
+                             "mnemonic",
                              "metadata",
                              "outputs",
                              "packages",
@@ -418,6 +414,7 @@ template("gen_snapshot_action") {
       !defined(invoker.script),
       "script must not be defined for $target_name. If there is a script use args instead.")
   _built_tool_action(target_name) {
+    mnemonic = "GEN_SNAPSHOT"
     if (product_mode) {
       tool = "$_dart_root/runtime/bin:gen_snapshot_product"
     } else {
diff --git a/utils/aot_snapshot.gni b/utils/aot_snapshot.gni
index 31a8492235d..647f320319a 100644
--- a/utils/aot_snapshot.gni
+++ b/utils/aot_snapshot.gni
@@ -52,6 +52,7 @@ template("aot_snapshot") {
   # simulator builds.
   kernel_label = target_name + "_dill"
   prebuilt_dart_action(kernel_label) {
+    mnemonic = "GEN_KERNEL"
     if (defined(invoker.pool)) {
       pool = invoker.pool
     }
@@ -148,8 +149,9 @@ template("aot_snapshot") {
 
   if (is_mac && codesigning_identity != "") {
     action(target_name) {
-      deps = [ ":$gen_snapshot_label" ]
+      mnemonic = "CODESIGN"
 
+      deps = [ ":$gen_snapshot_label" ]
       inputs = [ unsigned_snapshot ]
       outputs = [ signed_snapshot ]
 
diff --git a/utils/application_snapshot.gni b/utils/application_snapshot.gni
index eaa10251be8..b8a81fe60d9 100644
--- a/utils/application_snapshot.gni
+++ b/utils/application_snapshot.gni
@@ -120,6 +120,7 @@ template("application_snapshot") {
   # Build the kernel file using the prebuilt VM to speed up the debug and
   # simulator builds.
   prebuilt_dart_action(target_name + "_dill") {
+    mnemonic = "GEN_KERNEL"
     if (defined(invoker.pool)) {
       pool = invoker.pool
     }
@@ -145,7 +146,8 @@ template("application_snapshot") {
     depfile = "$output.d"
 
     vm_args = [
-      # Ensure gen_kernel.dart will use this SDK hash when consuming/producing kernel.
+      # Ensure gen_kernel.dart will use this SDK hash when consuming/producing
+      # kernel.
       "-Dsdk_hash=$sdk_hash",
     ]
 
@@ -190,6 +192,7 @@ template("application_snapshot") {
     }
   } else {
     dart_action(target_name) {
+      mnemonic = "APP_JIT"
       if (defined(invoker.pool)) {
         pool = invoker.pool
       }
@@ -202,8 +205,8 @@ template("application_snapshot") {
 
       outputs = [ output ]
 
-      # Explicitly set DFE so Dart doesn't implicitly depend on the kernel service
-      # snapshot (creating a circular dep. for kernel-service_snapshot).
+      # Explicitly set DFE so Dart doesn't implicitly depend on the kernel
+      # service snapshot (creating a circular dep. for kernel-service_snapshot).
       dfe = "NEVER_LOADED"
 
       vm_args = [
diff --git a/utils/ddc/BUILD.gn b/utils/ddc/BUILD.gn
index 23c191ffe5f..a4367518243 100644
--- a/utils/ddc/BUILD.gn
+++ b/utils/ddc/BUILD.gn
@@ -62,6 +62,7 @@ template("dart2js_compile") {
   rebased_output = rebase_path(out, root_build_dir)
 
   prebuilt_dart_action(target_name) {
+    mnemonic = "DART2JS"
     deps = invoker.deps + [ "../compiler:compile_dart2js_platform" ]
 
     inputs = [
@@ -201,6 +202,7 @@ template("ddc_compile") {
   #   * args: additional args to pass to dartdevc
 
   prebuilt_dart_action(target_name) {
+    mnemonic = "DDC"
     script = "../../pkg/dev_compiler/bin/dartdevc.dart"
     package_name = invoker.package
     out_dir = rebase_path("$js_gen_dir")
@@ -439,6 +441,7 @@ template("ddc_compile_sdk") {
   }
 
   prebuilt_dart_action(target_name) {
+    mnemonic = "DDC"
     deps = [
       ":ddc_files_stamp",
       ":ddc_platform",