diff --git a/.github/workflows/llm-c-evaluation.yml b/.github/workflows/llm-c-evaluation.yml
index 688cae33..56c8a7e9 100644
--- a/.github/workflows/llm-c-evaluation.yml
+++ b/.github/workflows/llm-c-evaluation.yml
@@ -5,6 +5,9 @@ concurrency:
   group: ${{ github.workflow }}-llm-nightly-test-${{ github.event.pull_request.number || github.run_id }}
   cancel-in-progress: true
 
+permissions:
+  contents: read
+
 # Controls when the action will run.
 on:
   schedule: