diff --git a/.github/workflows/pr-duplicate-check.lock.yml b/.github/workflows/pr-duplicate-check.lock.yml
index 516c669f7..627dee9d8 100644
--- a/.github/workflows/pr-duplicate-check.lock.yml
+++ b/.github/workflows/pr-duplicate-check.lock.yml
@@ -119,7 +119,7 @@ jobs:
         env:
           GH_AW_INFO_ENGINE_ID: "copilot"
           GH_AW_INFO_ENGINE_NAME: "GitHub Copilot CLI"
-          GH_AW_INFO_MODEL: ${{ vars.GH_AW_MODEL_AGENT_COPILOT || vars.GH_AW_DEFAULT_MODEL_COPILOT || 'auto' }}
+          GH_AW_INFO_MODEL: ${{ vars.GH_AW_MODEL_AGENT_COPILOT || vars.GH_AW_DEFAULT_MODEL_COPILOT || 'gpt-5-mini' }}
           GH_AW_INFO_VERSION: "1.0.78"
           GH_AW_INFO_AGENT_VERSION: "1.0.78"
           GH_AW_INFO_CLI_VERSION: "v0.85.4"
@@ -778,7 +778,7 @@ jobs:
           COPILOT_AGENT_RUNNER_TYPE: STANDALONE
           COPILOT_DUMMY_BYOK: dummy-byok-key-for-offline-mode
           COPILOT_GITHUB_TOKEN: ${{ github.token }}
-          COPILOT_MODEL: ${{ vars.GH_AW_MODEL_AGENT_COPILOT || vars.GH_AW_DEFAULT_MODEL_COPILOT || 'auto' }}
+          COPILOT_MODEL: ${{ vars.GH_AW_MODEL_AGENT_COPILOT || vars.GH_AW_DEFAULT_MODEL_COPILOT || 'gpt-5-mini' }}
           GH_AW_LLM_PROVIDER: github
           GH_AW_MAX_AI_CREDITS: ${{ vars.GH_AW_DEFAULT_MAX_AI_CREDITS || '1000' }}
           GH_AW_MAX_TURNS: ${{ vars.GH_AW_DEFAULT_MAX_TURNS || '' }}