diff --git a/.claude/hooks/enforce-makefile.py b/.claude/hooks/enforce-makefile.py
new file mode 100755
index 0000000..9c4c282
--- /dev/null
+++ b/.claude/hooks/enforce-makefile.py
@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+"""PreToolUse hook: intercept commands that should use Makefile targets instead."""
+
+import json
+import re
+import sys
+
+
+def deny(reason: str) -> None:
+    json.dump(
+        {
+            "hookSpecificOutput": {
+                "hookEventName": "PreToolUse",
+                "permissionDecision": "deny",
+                "permissionDecisionReason": reason,
+            }
+        },
+        sys.stdout,
+    )
+
+
+def main() -> None:
+    hook_input = json.loads(sys.stdin.read())
+    command = hook_input.get("tool_input", {}).get("command", "")
+
+    # Block direct invocation of the AI writing check script
+    # Match only actual script execution, not mentions in strings
+    if re.search(r"(uv\s+run\s+python|python3?|\./).*check_ai_writing\.py", command):
+        deny(
+            "Do not run the AI writing check script directly. "
+            "Instead, avoid using em dashes (U+2014) in any code or text you write. "
+            "The check runs automatically via pre-commit hooks."
+        )
+
+
+if __name__ == "__main__":
+    main()
diff --git a/.claude/settings.json b/.claude/settings.json
new file mode 100644
index 0000000..84b6f67
--- /dev/null
+++ b/.claude/settings.json
@@ -0,0 +1,16 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "uv run python \"$CLAUDE_PROJECT_DIR/.claude/hooks/enforce-makefile.py\"",
+            "timeout": 5
+          }
+        ]
+      }
+    ]
+  }
+}