From 011b2fbde1cf53c6c5175097485c33114c9403e3 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 22 Dec 2025 16:38:34 +0000
Subject: [PATCH 1/3] Configure workflow runs_on defaults for threading

- Linting workflows (test-py-lint, test-ts-lint): singlethreaded
- Testing workflows (test-*): multithreaded for parallel test execution
- Other workflows: singlethreaded
- Updated all workflows to use fromJSON(inputs.runs_on) for array support
---
 .github/workflows/build-next.yml               | 4 ++--
 .github/workflows/gh-submodules.yml            | 4 ++--
 .github/workflows/meta-regression-analysis.yml | 4 ++--
 .github/workflows/publish-ghcr.yml             | 4 ++--
 .github/workflows/regression-test.yml          | 4 ++--
 .github/workflows/run-branch-test.yml          | 8 ++++----
 .github/workflows/test-bandit.yml              | 8 ++++----
 .github/workflows/test-cs-nunit.yml            | 8 ++++----
 .github/workflows/test-cs-xunit.yml            | 8 ++++----
 .github/workflows/test-js-jest.yml             | 8 ++++----
 .github/workflows/test-js-mocha.yml            | 8 ++++----
 .github/workflows/test-py-lint.yml             | 2 +-
 .github/workflows/test-py-pytest.yml           | 4 ++--
 .github/workflows/test-py-unittest.yml         | 8 ++++----
 .github/workflows/test-storybook.yml           | 8 ++++----
 .github/workflows/test-ts-lint.yml             | 8 ++++----
 16 files changed, 49 insertions(+), 49 deletions(-)

diff --git a/.github/workflows/build-next.yml b/.github/workflows/build-next.yml
index fba4693..0a7ee68 100644
--- a/.github/workflows/build-next.yml
+++ b/.github/workflows/build-next.yml
@@ -11,7 +11,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
 jobs:
   lint:
     uses: ./.github/workflows/test-ts-lint.yml
@@ -21,7 +21,7 @@ jobs:
       lint_command: "npm run lint"
       fix_command: "npm run lint-fix"
   build-baremetal:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     name: Build / Baremetal
     needs: lint
     steps:
diff --git a/.github/workflows/gh-submodules.yml b/.github/workflows/gh-submodules.yml
index 4f779ab..e4b6576 100644
--- a/.github/workflows/gh-submodules.yml
+++ b/.github/workflows/gh-submodules.yml
@@ -15,11 +15,11 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
 
 jobs:
   manage-submodules:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     name: Manage Submodules
     permissions:
       contents: write
diff --git a/.github/workflows/meta-regression-analysis.yml b/.github/workflows/meta-regression-analysis.yml
index 46f7b5b..7fdbe9c 100644
--- a/.github/workflows/meta-regression-analysis.yml
+++ b/.github/workflows/meta-regression-analysis.yml
@@ -32,7 +32,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
     outputs:
       has_regressions:
         description: "Boolean indicating if regressions were found."
@@ -46,7 +46,7 @@ on:
 
 jobs:
   analyze:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       HAS_REGRESSIONS: ${{ steps.check-regressions-script.outputs.HAS_REGRESSIONS }}
       REGRESSION_COUNT: ${{ steps.check-regressions-script.outputs.REGRESSION_COUNT }}
diff --git a/.github/workflows/publish-ghcr.yml b/.github/workflows/publish-ghcr.yml
index 5dd8136..e55ef1c 100644
--- a/.github/workflows/publish-ghcr.yml
+++ b/.github/workflows/publish-ghcr.yml
@@ -23,11 +23,11 @@ on:
       runs_on:
         required: false
         type: string
-        default: "ubuntu-latest"
+        default: '["ubuntu-latest"]'
 jobs:
   build-and-push-ghcr:
     name: Build and Push Docker Image to GHCR
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     permissions:
       contents: read # To checkout the repository
       packages: write # To push packages to GHCR
diff --git a/.github/workflows/regression-test.yml b/.github/workflows/regression-test.yml
index 108644b..73cfca6 100644
--- a/.github/workflows/regression-test.yml
+++ b/.github/workflows/regression-test.yml
@@ -7,7 +7,7 @@ on:
         description: "Runner label for the regression analysis job."
         required: false
         type: string
-        default: "ubuntu-latest"
+        default: '["ubuntu-latest"]'
       baseline_label:
         description: "Display name for the baseline (target) test results."
         required: true
@@ -129,7 +129,7 @@ on:
 
 jobs:
   regression-analysis:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       has_regressions: ${{ steps.analyze.outputs.has_regressions }}
       regression_count: ${{ steps.analyze.outputs.regression_count }}
diff --git a/.github/workflows/run-branch-test.yml b/.github/workflows/run-branch-test.yml
index dc217bc..2d8a01f 100644
--- a/.github/workflows/run-branch-test.yml
+++ b/.github/workflows/run-branch-test.yml
@@ -16,7 +16,7 @@ on:
         description: "Runner label."
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
       parallel_workers:
         description: "Number of parallel pytest workers. Use 'auto' for CPU count."
         required: false
@@ -38,7 +38,7 @@ on:
 jobs:
   # Detect which test frameworks are present
   detect-frameworks:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       has_pytest: ${{ steps.detect.outputs.has_pytest }}
       # Future: has_jest, has_xunit, etc.
@@ -74,7 +74,7 @@ jobs:
   test-target:
     needs: detect-frameworks
     if: needs.detect-frameworks.outputs.has_pytest == 'true'
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.results.outputs.total }}
       passed: ${{ steps.results.outputs.passed }}
@@ -570,7 +570,7 @@ jobs:
     if: |
       always() &&
       (needs.compare.outputs.has_regressions == 'true' || needs.compare.result == 'failure')
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     steps:
       - name: Send notification
         env:
diff --git a/.github/workflows/test-bandit.yml b/.github/workflows/test-bandit.yml
index e67951d..82237bb 100644
--- a/.github/workflows/test-bandit.yml
+++ b/.github/workflows/test-bandit.yml
@@ -11,7 +11,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "ubuntu-latest"
+        default: '["ubuntu-latest"]'
     outputs:
       bandit_issues_json:
         description: "JSON output of Bandit issues on PR branch"
@@ -21,7 +21,7 @@ jobs:
   # Job 1: Run Bandit on the PR branch
   run-bandit:
     name: Run Bandit on PR Branch & Extract Results
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       bandit_issues_json: ${{ steps.extract-pr.outputs.BANDIT_JSON }}
     steps:
@@ -63,7 +63,7 @@ jobs:
   # Job 2: Run Bandit on the target branch for comparison
   run-bandit-on-target:
     name: Run Bandit on Target Branch
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       bandit_target_json: ${{ steps.extract-target.outputs.TARGET_JSON }}
     steps:
@@ -106,7 +106,7 @@ jobs:
   # Job 3: Compare the PR results against the target to detect regressions
   compare-bandit:
     name: Compare Bandit Issues (Regression Analysis)
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     needs: [run-bandit, run-bandit-on-target]
     steps:
       - name: Compare JSON
diff --git a/.github/workflows/test-cs-nunit.yml b/.github/workflows/test-cs-nunit.yml
index 719baf9..042a7bd 100644
--- a/.github/workflows/test-cs-nunit.yml
+++ b/.github/workflows/test-cs-nunit.yml
@@ -30,7 +30,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "Discord Webhook URL for failure notifications. If not provided, notifications are skipped."
@@ -72,7 +72,7 @@ on:
 
 jobs:
   test-source-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -402,7 +402,7 @@ jobs:
           if-no-files-found: ignore
 
   test-target-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -773,7 +773,7 @@ jobs:
         needs.compare-results.result == 'failure' ||
         needs.perform-regression-analysis.outputs.has_regressions == 'true'
       )
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       message_body: ${{ steps.construct_notification.outputs.message_body_out }}
       ping_user_ids: ${{ steps.construct_notification.outputs.ping_user_ids_out }}
diff --git a/.github/workflows/test-cs-xunit.yml b/.github/workflows/test-cs-xunit.yml
index e0eca3c..676c97d 100644
--- a/.github/workflows/test-cs-xunit.yml
+++ b/.github/workflows/test-cs-xunit.yml
@@ -30,7 +30,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "Discord Webhook URL for failure notifications. If not provided, notifications are skipped."
@@ -72,7 +72,7 @@ on:
 
 jobs:
   test-source-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -399,7 +399,7 @@ jobs:
           if-no-files-found: ignore
 
   test-target-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -770,7 +770,7 @@ jobs:
         needs.compare-results.result == 'failure' ||
         needs.perform-regression-analysis.outputs.has_regressions == 'true'
       )
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       message_body: ${{ steps.construct_notification.outputs.message_body_out }}
       ping_user_ids: ${{ steps.construct_notification.outputs.ping_user_ids_out }}
diff --git a/.github/workflows/test-js-jest.yml b/.github/workflows/test-js-jest.yml
index 3c74c75..71f3f60 100644
--- a/.github/workflows/test-js-jest.yml
+++ b/.github/workflows/test-js-jest.yml
@@ -40,7 +40,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "Discord Webhook URL for failure notifications. If not provided, notifications are skipped."
@@ -82,7 +82,7 @@ on:
 
 jobs:
   test-source-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.extract-results.outputs.total }}
       passed: ${{ steps.extract-results.outputs.passed }}
@@ -409,7 +409,7 @@ jobs:
           if-no-files-found: ignore
 
   test-target-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.check-collection.outputs.has_collection_errors == 'true' && steps.set-error-outputs.outputs.total || steps.extract-results.outputs.total }}
       passed: ${{ steps.check-collection.outputs.has_collection_errors == 'true' && steps.set-error-outputs.outputs.passed || steps.extract-results.outputs.passed }}
@@ -806,7 +806,7 @@ jobs:
         needs.compare-results.result == 'failure' ||
         needs.perform-regression-analysis.outputs.has_regressions == 'true'
       )
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       message_body: ${{ steps.construct_notification.outputs.message_body_out }}
       ping_user_ids: ${{ steps.construct_notification.outputs.ping_user_ids_out }}
diff --git a/.github/workflows/test-js-mocha.yml b/.github/workflows/test-js-mocha.yml
index 34f9c39..b47c52f 100644
--- a/.github/workflows/test-js-mocha.yml
+++ b/.github/workflows/test-js-mocha.yml
@@ -40,7 +40,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "Discord Webhook URL for failure notifications. If not provided, notifications are skipped."
@@ -82,7 +82,7 @@ on:
 
 jobs:
   test-source-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.extract-results.outputs.total }}
       passed: ${{ steps.extract-results.outputs.passed }}
@@ -439,7 +439,7 @@ jobs:
           if-no-files-found: ignore
 
   test-target-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.check-collection.outputs.has_collection_errors == 'true' && steps.set-error-outputs.outputs.total || steps.extract-results.outputs.total }}
       passed: ${{ steps.check-collection.outputs.has_collection_errors == 'true' && steps.set-error-outputs.outputs.passed || steps.extract-results.outputs.passed }}
@@ -869,7 +869,7 @@ jobs:
         needs.compare-results.result == 'failure' ||
         needs.perform-regression-analysis.outputs.has_regressions == 'true'
       )
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       message_body: ${{ steps.construct_notification.outputs.message_body_out }}
       ping_user_ids: ${{ steps.construct_notification.outputs.ping_user_ids_out }}
diff --git a/.github/workflows/test-py-lint.yml b/.github/workflows/test-py-lint.yml
index 6248055..f0caf80 100644
--- a/.github/workflows/test-py-lint.yml
+++ b/.github/workflows/test-py-lint.yml
@@ -6,7 +6,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: '["self-hosted", "multithreaded"]'
+        default: '["self-hosted", "singlethreaded"]'
     outputs:
       auto_formatted:
         description: "Whether Black auto-formatted files and pushed changes."
diff --git a/.github/workflows/test-py-pytest.yml b/.github/workflows/test-py-pytest.yml
index b366f33..284d7c1 100644
--- a/.github/workflows/test-py-pytest.yml
+++ b/.github/workflows/test-py-pytest.yml
@@ -17,7 +17,7 @@ on:
         description: "Runner label for the test job."
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
       artifact_name:
         description: "Name for the test results artifact."
         required: true
@@ -64,7 +64,7 @@ on:
 
 jobs:
   test:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.extract-results.outputs.total }}
       passed: ${{ steps.extract-results.outputs.passed }}
diff --git a/.github/workflows/test-py-unittest.yml b/.github/workflows/test-py-unittest.yml
index 6040e98..2c37a34 100644
--- a/.github/workflows/test-py-unittest.yml
+++ b/.github/workflows/test-py-unittest.yml
@@ -40,7 +40,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     secrets:
       DISCORD_WEBHOOK_URL:
         description: "Discord Webhook URL for failure notifications. If not provided, notifications are skipped."
@@ -82,7 +82,7 @@ on:
 
 jobs:
   test-source-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -642,7 +642,7 @@ PY
           if-no-files-found: ignore
 
   test-target-branch:
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     defaults:
       run:
         shell: bash
@@ -1020,7 +1020,7 @@ PY
         needs.compare-results.result == 'failure' ||
         needs.perform-regression-analysis.outputs.has_regressions == 'true'
       )
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       message_body: ${{ steps.construct_notification.outputs.message_body_out }}
       ping_user_ids: ${{ steps.construct_notification.outputs.ping_user_ids_out }}
diff --git a/.github/workflows/test-storybook.yml b/.github/workflows/test-storybook.yml
index eca7415..44c280b 100644
--- a/.github/workflows/test-storybook.yml
+++ b/.github/workflows/test-storybook.yml
@@ -21,7 +21,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "multithreaded"]'
     outputs:
       pr_has_errors:
         description: "Boolean indicating if the PR branch has Storybook test errors."
@@ -46,7 +46,7 @@ jobs:
     if: ${{ inputs.target_branch_to_compare != '' }}
     name: Test Target Branch Stories
     needs: [lint] # Ensure linting passes before running tests
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       total: ${{ steps.normalise-target.outputs.total }}
       passed: ${{ steps.normalise-target.outputs.passed }}
@@ -126,7 +126,7 @@ jobs:
   test-pr-branch-storybook:
     name: Test PR Branch Stories
     needs: [lint]
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       has_errors: ${{ steps.run-tests-pr.outcome == 'failure' || steps.normalise-pr.outputs.has_failures == 'true' }}
       failing_stories_json: ${{ steps.normalise-pr.outputs.failing_items_json }}
@@ -243,7 +243,7 @@ jobs:
 
   check-storybook-results:
     name: Check Storybook Results & Regressions
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     needs: [test-pr-branch-storybook, compare-results, perform-regression-analysis]
     if: always() # Always run to give a final status
     steps:
diff --git a/.github/workflows/test-ts-lint.yml b/.github/workflows/test-ts-lint.yml
index 9af248e..30e956a 100644
--- a/.github/workflows/test-ts-lint.yml
+++ b/.github/workflows/test-ts-lint.yml
@@ -29,7 +29,7 @@ on:
       runs_on:
         required: false
         type: string
-        default: "self-hosted"
+        default: '["self-hosted", "singlethreaded"]'
       target_branch_artifact_name:
         required: false
         type: string
@@ -55,7 +55,7 @@ jobs:
     # Only run if a target branch is specified for comparison
     if: ${{ inputs.target_branch_to_compare != '' }}
     name: Lint Target Branch
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       clean_files_json: ${{ steps.extract-clean-files.outputs.CLEAN_FILES_JSON }}
     steps:
@@ -136,7 +136,7 @@ jobs:
 
   lint-pr-branch:
     name: Lint PR Branch & Attempt Fixes
-    runs-on: ${{ inputs.runs_on }}
+    runs-on: ${{ fromJSON(inputs.runs_on) }}
     outputs:
       lint_errors_json: ${{ steps.extract-errors-pr.outputs.LINT_ERRORS_JSON }}
       has_lint_errors: ${{ steps.check-errors-pr.outputs.HAS_LINT_ERRORS }}
@@ -301,7 +301,7 @@ jobs:
 
   # check-results:
   #   name: Check Lint Results
-  #   runs-on: ${{ inputs.runs_on }}
+  #   runs-on: ${{ fromJSON(inputs.runs_on) }}
   #   needs: [lint-pr-branch, analyze-regressions]
   #   if: always()
   #   steps:

From 06fbaa05826d13fa16758b425a1331dfa868db71 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 22 Dec 2025 16:59:37 +0000
Subject: [PATCH 2/3] Fix pytest-xdist worker count to prevent OOM on
 constrained runners

Change parallel_workers default from 'auto' to '4'. The 'auto' setting
detects host/hypervisor CPUs (e.g., 20) rather than container-allocated
resources, causing OOM kills when running on singlethreaded runners
with 1 CPU and limited RAM.
---
 .github/workflows/test-py-pytest.yml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/test-py-pytest.yml b/.github/workflows/test-py-pytest.yml
index 284d7c1..945a68d 100644
--- a/.github/workflows/test-py-pytest.yml
+++ b/.github/workflows/test-py-pytest.yml
@@ -23,10 +23,10 @@ on:
         required: true
         type: string
       parallel_workers:
-        description: "Number of parallel workers for pytest-xdist. Use 'auto' for CPU count, or a number. Set to '1' to disable."
+        description: "Number of parallel workers for pytest-xdist. Use 'auto' for CPU count (caution: detects host CPUs, not container), or a number. Set to '1' to disable."
         required: false
         type: string
-        default: "auto"
+        default: "4"
     outputs:
       total:
         description: "Total number of tests"

From a7b5ba636a906faf78caced357d2204eb5b907e7 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 22 Dec 2025 17:01:16 +0000
Subject: [PATCH 3/3] Auto-detect pytest workers based on runner type

- Multithreaded runner: 6 workers (matches 8 CPU / 8GB RAM)
- Singlethreaded runner: 1 worker (matches 1 CPU / 1GB RAM)

Default is now empty string which triggers auto-detection from the
runs_on input. Explicit values can still be passed to override.
---
 .github/workflows/run-branch-test.yml |  4 ++--
 .github/workflows/test-py-pytest.yml  | 21 ++++++++++++++++-----
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/.github/workflows/run-branch-test.yml b/.github/workflows/run-branch-test.yml
index 2d8a01f..a57bcc0 100644
--- a/.github/workflows/run-branch-test.yml
+++ b/.github/workflows/run-branch-test.yml
@@ -18,10 +18,10 @@ on:
         type: string
         default: '["self-hosted", "multithreaded"]'
       parallel_workers:
-        description: "Number of parallel pytest workers. Use 'auto' for CPU count."
+        description: "Number of parallel pytest workers. Leave empty for auto-detect (6 for multithreaded, 1 for singlethreaded). Use 'auto' for CPU count (caution: detects host CPUs)."
         required: false
         type: string
-        default: "auto"
+        default: ""
     secrets:
       DISCORD_WEBHOOK_URL:
         required: false
diff --git a/.github/workflows/test-py-pytest.yml b/.github/workflows/test-py-pytest.yml
index 945a68d..e5ec325 100644
--- a/.github/workflows/test-py-pytest.yml
+++ b/.github/workflows/test-py-pytest.yml
@@ -23,10 +23,10 @@ on:
         required: true
         type: string
       parallel_workers:
-        description: "Number of parallel workers for pytest-xdist. Use 'auto' for CPU count (caution: detects host CPUs, not container), or a number. Set to '1' to disable."
+        description: "Number of parallel workers for pytest-xdist. Leave empty for auto-detect based on runner (6 for multithreaded, 1 for singlethreaded). Use 'auto' for CPU count (caution: detects host CPUs, not container), or a number."
         required: false
         type: string
-        default: "4"
+        default: ""
     outputs:
       total:
         description: "Total number of tests"
@@ -152,10 +152,21 @@ jobs:
         continue-on-error: true
         if: steps.check-collection.outputs.has_collection_errors != 'true'
         run: |
-          echo "Running tests with ${{ inputs.parallel_workers }} workers..."
+          # Determine worker count based on input or runner type
+          WORKERS="${{ inputs.parallel_workers }}"
+          if [ -z "$WORKERS" ]; then
+            # Auto-detect based on runner type
+            if echo '${{ inputs.runs_on }}' | grep -q "multithreaded"; then
+              WORKERS="6"
+            else
+              WORKERS="1"
+            fi
+          fi
+          echo "Running tests with $WORKERS workers..."
+
           PARALLEL_FLAG=""
-          if [ "${{ inputs.parallel_workers }}" != "1" ]; then
-            PARALLEL_FLAG="-n ${{ inputs.parallel_workers }}"
+          if [ "$WORKERS" != "1" ]; then
+            PARALLEL_FLAG="-n $WORKERS"
           fi
 
           # Run pytest and capture exit code