[chromium_swarming] switch to go swarming client

This CL switches swarming client from python to go for the recipes using chromium_swarming module.

Bug: 894045
Change-Id: I4ad927db05e3b3c76f2cb19e8c5a9e758768af86
Reviewed-on: https://chromium-review.googlesource.com/c/1402223
Commit-Queue: Takuto Ikuta <tikuta@chromium.org>
Auto-Submit: Takuto Ikuta <tikuta@chromium.org>
Reviewed-by: Shuotao Gao <stgao@chromium.org>
Reviewed-by: Marc-Antoine Ruel <maruel@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
diff --git a/scripts/slave/README.recipes.md b/scripts/slave/README.recipes.md
index efec01c..9cbad3a 100644
--- a/scripts/slave/README.recipes.md
+++ b/scripts/slave/README.recipes.md
@@ -1396,7 +1396,7 @@
 
 #### **class [ChromiumSwarmingApi](/scripts/slave/recipe_modules/chromium_swarming/api.py#34)([RecipeApi][recipe_engine/wkt/RecipeApi]):**
 
-&mdash; **def [configure\_swarming](/scripts/slave/recipe_modules/chromium_swarming/api.py#35)(self, project_name, precommit, mastername=None, default_priority=None, use_go_client=False):**
+&mdash; **def [configure\_swarming](/scripts/slave/recipe_modules/chromium_swarming/api.py#35)(self, project_name, precommit, mastername=None, default_priority=None):**
 
 Configures default swarming dimensions and tags.
 
@@ -1412,7 +1412,6 @@
       default priority of swarming tasks.
   default_priority: optional default_priority to use. Will override the
       priority name inherited from the mastername (or the global default).
-  use_go_client: optional, use go client for swarming if set.
 ### *recipe_modules* / [chromium\_tests](/scripts/slave/recipe_modules/chromium_tests)
 
 [DEPS](/scripts/slave/recipe_modules/chromium_tests/__init__.py#1): [adb](#recipe_modules-adb), [archive](#recipe_modules-archive), [bisect\_tester](#recipe_modules-bisect_tester), [bisect\_tester\_staging](#recipe_modules-bisect_tester_staging), [build](#recipe_modules-build), [chromium](#recipe_modules-chromium), [chromium\_android](#recipe_modules-chromium_android), [chromium\_checkout](#recipe_modules-chromium_checkout), [chromium\_swarming](#recipe_modules-chromium_swarming), [clang\_coverage](#recipe_modules-clang_coverage), [commit\_position](#recipe_modules-commit_position), [filter](#recipe_modules-filter), [gn](#recipe_modules-gn), [goma](#recipe_modules-goma), [isolate](#recipe_modules-isolate), [perf\_dashboard](#recipe_modules-perf_dashboard), [puppet\_service\_account](#recipe_modules-puppet_service_account), [swarming](#recipe_modules-swarming), [test\_results](#recipe_modules-test_results), [test\_utils](#recipe_modules-test_utils), [traceback](#recipe_modules-traceback), [trigger](#recipe_modules-trigger), [zip](#recipe_modules-zip), [depot\_tools/bot\_update][depot_tools/recipe_modules/bot_update], [depot\_tools/gclient][depot_tools/recipe_modules/gclient], [depot\_tools/gsutil][depot_tools/recipe_modules/gsutil], [depot\_tools/tryserver][depot_tools/recipe_modules/tryserver], [recipe\_engine/buildbucket][recipe_engine/recipe_modules/buildbucket], [recipe\_engine/context][recipe_engine/recipe_modules/context], [recipe\_engine/file][recipe_engine/recipe_modules/file], [recipe\_engine/json][recipe_engine/recipe_modules/json], [recipe\_engine/path][recipe_engine/recipe_modules/path], [recipe\_engine/platform][recipe_engine/recipe_modules/platform], [recipe\_engine/properties][recipe_engine/recipe_modules/properties], [recipe\_engine/python][recipe_engine/recipe_modules/python], [recipe\_engine/raw\_io][recipe_engine/recipe_modules/raw_io], [recipe\_engine/runtime][recipe_engine/recipe_modules/runtime], [recipe\_engine/scheduler][recipe_engine/recipe_modules/scheduler], [recipe\_engine/step][recipe_engine/recipe_modules/step], [recipe\_engine/tempfile][recipe_engine/recipe_modules/tempfile], [recipe\_engine/time][recipe_engine/recipe_modules/time]
@@ -1572,7 +1571,7 @@
 
 &mdash; **def [trigger\_child\_builds](/scripts/slave/recipe_modules/chromium_tests/api.py#548)(self, mastername, buildername, update_step, bot_db, additional_properties=None):**
 
-&mdash; **def [trybot\_steps](/scripts/slave/recipe_modules/chromium_tests/api.py#1182)(self, builders=None, trybots=None):**
+&mdash; **def [trybot\_steps](/scripts/slave/recipe_modules/chromium_tests/api.py#1181)(self, builders=None, trybots=None):**
 
 &emsp; **@property**<br>&mdash; **def [trybots](/scripts/slave/recipe_modules/chromium_tests/api.py#68)(self):**
 
@@ -4032,33 +4031,33 @@
 
 &emsp; **@property**<br>&mdash; **def [bucketname](/scripts/slave/recipe_modules/webrtc/api.py#139)(self):**
 
-&mdash; **def [build\_android\_archive](/scripts/slave/recipe_modules/webrtc/api.py#422)(self):**
+&mdash; **def [build\_android\_archive](/scripts/slave/recipe_modules/webrtc/api.py#421)(self):**
 
 &emsp; **@property**<br>&mdash; **def [buildername](/scripts/slave/recipe_modules/webrtc/api.py#146)(self):**
 
-&mdash; **def [check\_swarming\_version](/scripts/slave/recipe_modules/webrtc/api.py#296)(self):**
+&mdash; **def [check\_swarming\_version](/scripts/slave/recipe_modules/webrtc/api.py#295)(self):**
 
-&mdash; **def [checkout](/scripts/slave/recipe_modules/webrtc/api.py#236)(self, \*\*kwargs):**
+&mdash; **def [checkout](/scripts/slave/recipe_modules/webrtc/api.py#235)(self, \*\*kwargs):**
 
-&mdash; **def [clean\_test\_output](/scripts/slave/recipe_modules/webrtc/api.py#505)(self):**
+&mdash; **def [clean\_test\_output](/scripts/slave/recipe_modules/webrtc/api.py#504)(self):**
 
 Remove all test output in out/, since we have tests leaking files.
 
-&mdash; **def [cleanup](/scripts/slave/recipe_modules/webrtc/api.py#498)(self):**
+&mdash; **def [cleanup](/scripts/slave/recipe_modules/webrtc/api.py#497)(self):**
 
-&mdash; **def [compile](/scripts/slave/recipe_modules/webrtc/api.py#321)(self, phase=None):**
+&mdash; **def [compile](/scripts/slave/recipe_modules/webrtc/api.py#320)(self, phase=None):**
 
 &mdash; **def [configure\_isolate](/scripts/slave/recipe_modules/webrtc/api.py#186)(self, phase=None):**
 
 &mdash; **def [configure\_swarming](/scripts/slave/recipe_modules/webrtc/api.py#198)(self):**
 
-&mdash; **def [download\_audio\_quality\_tools](/scripts/slave/recipe_modules/webrtc/api.py#268)(self):**
+&mdash; **def [download\_audio\_quality\_tools](/scripts/slave/recipe_modules/webrtc/api.py#267)(self):**
 
-&mdash; **def [download\_video\_quality\_tools](/scripts/slave/recipe_modules/webrtc/api.py#276)(self):**
+&mdash; **def [download\_video\_quality\_tools](/scripts/slave/recipe_modules/webrtc/api.py#275)(self):**
 
-&mdash; **def [extract\_build](/scripts/slave/recipe_modules/webrtc/api.py#479)(self):**
+&mdash; **def [extract\_build](/scripts/slave/recipe_modules/webrtc/api.py#478)(self):**
 
-&mdash; **def [get\_binary\_sizes](/scripts/slave/recipe_modules/webrtc/api.py#338)(self, files=None, base_dir=None):**
+&mdash; **def [get\_binary\_sizes](/scripts/slave/recipe_modules/webrtc/api.py#337)(self, files=None, base_dir=None):**
 
 &mdash; **def [get\_bot](/scripts/slave/recipe_modules/webrtc/api.py#150)(self, bucketname, buildername):**
 
@@ -4066,17 +4065,17 @@
 
 &emsp; **@property**<br>&mdash; **def [mastername](/scripts/slave/recipe_modules/webrtc/api.py#157)(self):**
 
-&mdash; **def [maybe\_trigger](/scripts/slave/recipe_modules/webrtc/api.py#388)(self):**
+&mdash; **def [maybe\_trigger](/scripts/slave/recipe_modules/webrtc/api.py#387)(self):**
 
-&mdash; **def [package\_apprtcmobile](/scripts/slave/recipe_modules/webrtc/api.py#463)(self):**
+&mdash; **def [package\_apprtcmobile](/scripts/slave/recipe_modules/webrtc/api.py#462)(self):**
 
-&mdash; **def [package\_build](/scripts/slave/recipe_modules/webrtc/api.py#412)(self):**
+&mdash; **def [package\_build](/scripts/slave/recipe_modules/webrtc/api.py#411)(self):**
 
 &mdash; **def [related\_bots](/scripts/slave/recipe_modules/webrtc/api.py#161)(self):**
 
-&mdash; **def [run\_mb](/scripts/slave/recipe_modules/webrtc/api.py#305)(self, phase=None):**
+&mdash; **def [run\_mb](/scripts/slave/recipe_modules/webrtc/api.py#304)(self, phase=None):**
 
-&mdash; **def [runtests](/scripts/slave/recipe_modules/webrtc/api.py#354)(self, phase=None):**
+&mdash; **def [runtests](/scripts/slave/recipe_modules/webrtc/api.py#353)(self, phase=None):**
 
 Add a suite of test steps.
 
diff --git a/scripts/slave/recipe_modules/chromium_swarming/api.py b/scripts/slave/recipe_modules/chromium_swarming/api.py
index b5c6fa2..034f0ef 100644
--- a/scripts/slave/recipe_modules/chromium_swarming/api.py
+++ b/scripts/slave/recipe_modules/chromium_swarming/api.py
@@ -33,7 +33,7 @@
 
 class ChromiumSwarmingApi(recipe_api.RecipeApi):
   def configure_swarming(self, project_name, precommit, mastername=None,
-                         default_priority=None, use_go_client=False):
+                         default_priority=None):
     """Configures default swarming dimensions and tags.
 
     Uses the 'chromium' global config to determine target platform defaults,
@@ -48,7 +48,6 @@
           default priority of swarming tasks.
       default_priority: optional default_priority to use. Will override the
           priority name inherited from the mastername (or the global default).
-      use_go_client: optional, use go client for swarming if set.
     """
 
     # Set platform-specific default dims.
@@ -98,5 +97,4 @@
       self.m.swarming.add_default_tag('purpose:luci')
 
     # TODO(tikuta): Remove this (crbug.com/894045).
-    if use_go_client:
-      self.m.swarming.use_go_client = True
+    self.m.swarming.use_go_client = True
diff --git a/scripts/slave/recipe_modules/chromium_swarming/tests/configure_swarming.py b/scripts/slave/recipe_modules/chromium_swarming/tests/configure_swarming.py
index fddcd2a..c8408d7 100644
--- a/scripts/slave/recipe_modules/chromium_swarming/tests/configure_swarming.py
+++ b/scripts/slave/recipe_modules/chromium_swarming/tests/configure_swarming.py
@@ -19,8 +19,7 @@
   api.chromium_swarming.configure_swarming(
       'chromium',
       precommit=api.properties['precommit'],
-      default_priority=api.properties.get('default_priority'),
-      use_go_client=api.properties.get('use_go_client'))
+      default_priority=api.properties.get('default_priority'))
 
 
 def GenTests(api):
@@ -63,8 +62,3 @@
       api.properties(precommit=False, default_priority=10) +
       api.runtime(is_luci=True, is_experimental=False) +
       api.post_process(post_process.DropExpectation))
-
-  yield (
-      api.test('use_go_client') +
-      api.properties(precommit=False, use_go_client=True) +
-      api.post_process(post_process.DropExpectation))
diff --git a/scripts/slave/recipe_modules/chromium_tests/api.py b/scripts/slave/recipe_modules/chromium_tests/api.py
index 2788052..55d9095 100644
--- a/scripts/slave/recipe_modules/chromium_tests/api.py
+++ b/scripts/slave/recipe_modules/chromium_tests/api.py
@@ -1172,8 +1172,7 @@
 
     self.m.chromium_swarming.configure_swarming(
         'chromium', precommit=False, mastername=mastername,
-        default_priority=bot_config.get('swarming_default_priority'),
-        use_go_client=True)
+        default_priority=bot_config.get('swarming_default_priority'))
     test_runner = self.create_test_runner(
         tests, serialize_tests=bot_config.get('serialize_tests'))
     with self.wrap_chromium_tests(bot_config, tests):
@@ -1251,7 +1250,7 @@
     self.configure_build(bot_config_object, override_bot_type='builder_tester')
 
     self.m.chromium_swarming.configure_swarming(
-      'chromium', precommit=True, use_go_client=True)
+      'chromium', precommit=True)
 
     self.m.chromium.apply_config('trybot_flavor')
 
diff --git a/scripts/slave/recipe_modules/webrtc/api.py b/scripts/slave/recipe_modules/webrtc/api.py
index 2b3be98..e8dbf81 100644
--- a/scripts/slave/recipe_modules/webrtc/api.py
+++ b/scripts/slave/recipe_modules/webrtc/api.py
@@ -201,8 +201,7 @@
       self.m.chromium_swarming.configure_swarming(
           'webrtc',
           precommit=self.m.tryserver.is_tryserver,
-          mastername=self.mastername,
-          use_go_client=True)
+          mastername=self.mastername)
       self.m.swarming.set_default_dimension(
           'os',
           self.m.swarming.prefered_os_dimension(
diff --git a/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_blink_web_tests.json b/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_blink_web_tests.json
index d1ef7b2..7343049 100644
--- a/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_blink_web_tests.json
+++ b/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_blink_web_tests.json
@@ -1320,19 +1320,22 @@
       "[]",
       "--build-properties",
       "{\"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/flake\", \"skip_tests\": false, \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_revision\": \"r0\", \"tests\": {\"blink_web_tests\": [\"fast/dummy/test.html\"]}}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"blink_web_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"blink_web_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_swarming_tests.json b/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_swarming_tests.json
index f525955..a37ca7b 100644
--- a/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_swarming_tests.json
+++ b/scripts/slave/recipes/findit/chromium/flake.expected/flakiness_swarming_tests.json
@@ -1373,19 +1373,22 @@
       "[]",
       "--build-properties",
       "{\"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/flake\", \"skip_tests\": false, \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_revision\": \"r0\", \"tests\": {\"browser_tests\": [\"Test.One\"]}}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:0\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:1\": {\"shard_index\": 1, \"task_id\": \"10100\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10100\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:2\": {\"shard_index\": 2, \"task_id\": \"10200\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10200\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:3\": {\"shard_index\": 3, \"task_id\": \"10300\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10300\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:4\": {\"shard_index\": 4, \"task_id\": \"10400\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10400\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:5\": {\"shard_index\": 5, \"task_id\": \"10500\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10500\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:6\": {\"shard_index\": 6, \"task_id\": \"10600\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10600\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:7\": {\"shard_index\": 7, \"task_id\": \"10700\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10700\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:8\": {\"shard_index\": 8, \"task_id\": \"10800\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10800\"}, \"browser_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1:10:9\": {\"shard_index\": 9, \"task_id\": \"10900\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10900\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}, {\"task_id\": \"10100\"}, {\"task_id\": \"10200\"}, {\"task_id\": \"10300\"}, {\"task_id\": \"10400\"}, {\"task_id\": \"10500\"}, {\"task_id\": \"10600\"}, {\"task_id\": \"10700\"}, {\"task_id\": \"10800\"}, {\"task_id\": \"10900\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/flake.expected/use_build_parameter_for_tests.json b/scripts/slave/recipes/findit/chromium/flake.expected/use_build_parameter_for_tests.json
index c3cb4b8..2544d6a 100644
--- a/scripts/slave/recipes/findit/chromium/flake.expected/use_build_parameter_for_tests.json
+++ b/scripts/slave/recipes/findit/chromium/flake.expected/use_build_parameter_for_tests.json
@@ -1340,19 +1340,22 @@
       "[]",
       "--build-properties",
       "{\"bot_id\": \"build1-a1\", \"buildbucket\": \"{\\\"build\\\": {\\\"id\\\": 1}}\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/flake\", \"skip_tests\": false, \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_revision\": \"r0\"}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/all_test_failed.json b/scripts/slave/recipes/findit/chromium/test.expected/all_test_failed.json
index a7ad68a..ebb406b 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/all_test_failed.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/all_test_failed.json
@@ -1224,19 +1224,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": false, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/all_test_passed.json b/scripts/slave/recipes/findit/chromium/test.expected/all_test_passed.json
index b584d3a..64e5863 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/all_test_passed.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/all_test_passed.json
@@ -1224,19 +1224,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/blink_web_tests.json b/scripts/slave/recipes/findit/chromium/test.expected/blink_web_tests.json
index 3ad5434..92c3eab 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/blink_web_tests.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/blink_web_tests.json
@@ -1336,19 +1336,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"blink_web_tests\": [\"fast/Test/One.html\", \"fast/Test/Two.html\", \"dummy/Three.js\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"blink_web_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"blink_web_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2413,19 +2416,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"blink_web_tests\": [\"fast/Test/One.html\", \"fast/Test/Two.html\", \"dummy/Three.js\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"blink_web_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"blink_web_tests (r0)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/builder_as_tester.json b/scripts/slave/recipes/findit/chromium/test.expected/builder_as_tester.json
index b9e3b27..c3328a5 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/builder_as_tester.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/builder_as_tester.json
@@ -1192,19 +1192,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"linux_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.linux\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.linux\", \"target_testername\": \"linux-ozone-rel\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"services_unittests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/linux/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"services_unittests (r1)/Ubuntu-14.04/[dummy has/linux_chromium_variable/1\", \"tasks\": {\"services_unittests (r1)/Ubuntu-14.04/[dummy has/linux_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_consecutive_culprits.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_consecutive_culprits.json
index 0f8d7b0..e743069 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_consecutive_culprits.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_consecutive_culprits.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3421,19 +3427,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_first_sub_range.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_first_sub_range.json
index b786b79..ad22bf6 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_first_sub_range.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_first_sub_range.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": false, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": false, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3421,19 +3427,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": false, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_last_sub_range.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_last_sub_range.json
index 8f0dad2..7d79a12 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_last_sub_range.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_last_sub_range.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_middle_sub_range.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_middle_sub_range.json
index d0333ac..d17e594 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_middle_sub_range.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_culprit_in_middle_sub_range.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3421,19 +3427,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -4462,19 +4471,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"130000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/130000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"130000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_steps_multiple_culprits.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_steps_multiple_culprits.json
index b7ffd2a..26a4fff 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_steps_multiple_culprits.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_steps_multiple_culprits.json
@@ -1499,19 +1499,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"browser_tests\": [\"Test.browser_One\"], \"gl_tests\": [\"Test.gl_One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"browser_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"browser_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -1627,19 +1630,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"browser_tests\": [\"Test.browser_One\"], \"gl_tests\": [\"Test.gl_One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2686,19 +2692,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"browser_tests\": [\"Test.browser_One\"], \"gl_tests\": [\"Test.gl_One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"browser_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"browser_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3745,19 +3754,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"browser_tests\": [\"Test.browser_One\"], \"gl_tests\": [\"Test.gl_One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"130000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/130000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"130000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -4792,19 +4804,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r6\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"browser_tests\": [\"Test.browser_One\"], \"gl_tests\": [\"Test.gl_One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"140000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/140000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"140000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/findit_tests_multiple_culprits.json b/scripts/slave/recipes/findit/chromium/test.expected/findit_tests_multiple_culprits.json
index 8f5bebb..593832b 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/findit_tests_multiple_culprits.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/findit_tests_multiple_culprits.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r5\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2392,19 +2395,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r5\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r5)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3445,19 +3451,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r5\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r6)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -4498,19 +4507,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r5\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"130000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/130000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"130000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -5539,19 +5551,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r5\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"140000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/140000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"140000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/flaky_tests.json b/scripts/slave/recipes/findit/chromium/test.expected/flaky_tests.json
index d20d357..ac4ed7a 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/flaky_tests.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/flaky_tests.json
@@ -1224,19 +1224,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
@@ -2230,19 +2233,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r0)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r0)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/only_one_test_passed.json b/scripts/slave/recipes/findit/chromium/test.expected/only_one_test_passed.json
index 42fc7ce..85bb1e1 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/only_one_test_passed.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/only_one_test_passed.json
@@ -1224,19 +1224,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
@@ -2230,19 +2233,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\", \"Test.Three\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r0)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"gl_tests (r0)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/remove_culprits_for_flaky_failures.json b/scripts/slave/recipes/findit/chromium/test.expected/remove_culprits_for_flaky_failures.json
index ffb9294..58e9584 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/remove_culprits_for_flaky_failures.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/remove_culprits_for_flaky_failures.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\", \"Test.Two\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/swarming_tests.json b/scripts/slave/recipes/findit/chromium/test.expected/swarming_tests.json
index 00d5211..94d1ca7 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/swarming_tests.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/swarming_tests.json
@@ -1334,19 +1334,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r1)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/unaffected_test_skipped_by_analyze.json b/scripts/slave/recipes/findit/chromium/test.expected/unaffected_test_skipped_by_analyze.json
index 3522e20..0cb66c6 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/unaffected_test_skipped_by_analyze.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/unaffected_test_skipped_by_analyze.json
@@ -1331,19 +1331,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r1\", \"bot_id\": \"build1-a1\", \"buildername\": \"win_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.win\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.win\", \"target_testername\": \"Win7 Tests (1)\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"affected_tests\": [\"Test.One\"], \"unaffected_tests\": [\"Test.Two\"]}, \"use_analyze\": true}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]\\win\\src\\tools\\swarming_client\\swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"affected_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\", \"tasks\": {\"affected_tests (r1)/Windows-7-SP1/[dummy has/win_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env_prefixes": {
       "PATH": [
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/use_abbreviated_revision_in_step_name.json b/scripts/slave/recipes/findit/chromium/test.expected/use_abbreviated_revision_in_step_name.json
index b618197..01a3271 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/use_abbreviated_revision_in_step_name.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/use_abbreviated_revision_in_step_name.json
@@ -1334,19 +1334,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"gfedcba0987654321\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"1234567890abcdefg\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": false, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (gfedcba)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (gfedcba)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/use_analyze_set_to_False_for_non_linear_try_job.json b/scripts/slave/recipes/findit/chromium/test.expected/use_analyze_set_to_False_for_non_linear_try_job.json
index 85ccec7..094b165 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/use_analyze_set_to_False_for_non_linear_try_job.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/use_analyze_set_to_False_for_non_linear_try_job.json
@@ -1339,19 +1339,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": true}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2380,19 +2383,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"tests\": {\"gl_tests\": [\"Test.One\"]}, \"use_analyze\": true}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests.json b/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests.json
index 3c8ce09..6bbb465 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests.json
@@ -1361,19 +1361,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": \"{\\\"build\\\": {\\\"id\\\": 1}}\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2406,19 +2409,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": \"{\\\"build\\\": {\\\"id\\\": 1}}\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3451,19 +3457,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": \"{\\\"build\\\": {\\\"id\\\": 1}}\", \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
diff --git a/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests_non_json_buildbucket.json b/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests_non_json_buildbucket.json
index 20d4b17..5502fee 100644
--- a/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests_non_json_buildbucket.json
+++ b/scripts/slave/recipes/findit/chromium/test.expected/use_build_parameter_for_tests_non_json_buildbucket.json
@@ -1361,19 +1361,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": {\"build\": {\"id\": 1}}, \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r2)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"10000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -2406,19 +2409,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": {\"build\": {\"id\": 1}}, \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r3)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"110000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/110000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"110000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"
@@ -3451,19 +3457,22 @@
       "[]",
       "--build-properties",
       "{\"bad_revision\": \"r6\", \"bot_id\": \"build1-a1\", \"buildbucket\": {\"build\": {\"id\": 1}}, \"buildername\": \"mac_chromium_variable\", \"buildnumber\": 1, \"good_revision\": \"r0\", \"got_angle_revision\": \"fac9503c46405f77757b9a728eb85b8d7bc6080c\", \"got_angle_revision_cp\": \"refs/heads/master@{#297276}\", \"got_buildtools_revision\": \"f0319a328b2809876916353cb994259692140934\", \"got_buildtools_revision_cp\": \"refs/heads/master@{#182578}\", \"got_dawn_revision\": \"1b5c932bc9a9a35c66edea3914fb675742d57cc2\", \"got_dawn_revision_cp\": \"refs/heads/master@{#51819}\", \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", \"got_revision\": \"f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9\", \"got_revision_cp\": \"refs/heads/master@{#170242}\", \"got_swarming_client_revision\": \"a0ee5d99f1d4b38ddaa4c759c837980b63b99566\", \"got_swarming_client_revision_cp\": \"refs/heads/master@{#276089}\", \"got_v8_revision\": \"801ada225ddc271c132c3a35f03975671d43e399\", \"got_v8_revision_cp\": \"refs/heads/master@{#43426}\", \"got_webrtc_revision\": \"0f90628433546e61d9268596da93418c623137f4\", \"got_webrtc_revision_cp\": \"refs/heads/master@{#120644}\", \"mastername\": \"tryserver.chromium.mac\", \"path_config\": \"kitchen\", \"recipe\": \"findit/chromium/test\", \"suspected_revisions\": [\"r3\", \"r4\"], \"target_mastername\": \"chromium.mac\", \"target_testername\": \"Mac10.13 Tests\", \"test_on_good_revision\": true, \"test_repeat_count\": 20, \"use_analyze\": false}",
+      "--use-go-client",
+      "--summary-json-file",
+      "/path/to/tmp/json",
       "--",
-      "python",
-      "-u",
-      "[BUILDER_CACHE]/mac/src/tools/swarming_client/swarming.py",
+      "swarming",
       "collect",
-      "--swarming",
+      "-server",
       "https://chromium-swarm.appspot.com",
-      "--decorate",
-      "--print-status-updates",
-      "--json",
-      "{\"base_task_name\": \"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\", \"tasks\": {\"gl_tests (r4)/Mac-10.13/[dummy has/mac_chromium_variable/1\": {\"shard_index\": 0, \"task_id\": \"120000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/120000\"}}}",
-      "--task-summary-json",
-      "/path/to/tmp/json"
+      "-worker",
+      "50",
+      "-task-summary-python",
+      "-task-output-stdout",
+      "json",
+      "-verbose",
+      "-requests-json",
+      "{\"tasks\": [{\"task_id\": \"120000\"}]}"
     ],
     "env": {
       "FORCE_MAC_TOOLCHAIN": "1"