diff --git a/pyproject.toml b/pyproject.toml
index 5c3896ed2d..1d32b97d6d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -261,6 +261,7 @@ select = ["F", "I"]
 # Without this, ruff classifies prime_rl.configs.* as third-party because it
 # doesn't live under src/.
 known-first-party = ["prime_rl"]
+known-third-party = ["verifiers", "renderers", "pydantic_config"]
 
 [tool.ruff]
 line-length = 120