Clarify expected nulls in fault viewer fields

README.md

@@ -37,7 +37,7 @@ All tasks are synthetic and generated with deterministic seeds to ensure reprodu
 ## Repository and Evaluator
 
 - Project repository (code + evaluator + baselines):
-  https://github.com/akgitrepos/toolmisusebench
+  `https://github.com/akgitrepos/toolmisusebench`
 - Recommended evaluation flow uses the project CLI and harness.
 
 ## Supported Evaluation Use Cases
@@ -99,6 +99,15 @@ Supported fault types:
 
 Faults are declaratively specified per task and replayed deterministically.
 
+## Viewer Note on Null Values
+
+In the Hugging Face table viewer, nested fields inside `fault_plan.trigger` and `fault_plan.payload`
+may appear as `null` for some rows.
+
+This is expected: different fault types use different subsets of fields, and the viewer displays a
+unified schema across all rows. A `null` value in this context typically means "not applicable for
+this fault type," not missing or corrupted data.
+
 ## Data Generation
 
 Generated synthetically using deterministic templates, seeded randomization, and task-level coherence checks.