diff --git a/tests/core/pyspec/eth2spec/test/helpers/fork_choice.py b/tests/core/pyspec/eth2spec/test/helpers/fork_choice.py
index ba4f294bc0..e0e3547222 100644
--- a/tests/core/pyspec/eth2spec/test/helpers/fork_choice.py
+++ b/tests/core/pyspec/eth2spec/test/helpers/fork_choice.py
@@ -181,11 +181,8 @@ def add_block(spec,
     # Check blob_data
     if blob_data is not None:
         blobs = spec.List[spec.Blob, spec.MAX_BLOBS_PER_BLOCK](blob_data.blobs)
-        if len(blobs) > 0:
-            blobs_root = blobs.hash_tree_root()
-            yield get_blobs_file_name(blobs_root=blobs_root), blobs
-        else:
-            blobs_root = None
+        blobs_root = blobs.hash_tree_root()
+        yield get_blobs_file_name(blobs_root=blobs_root), blobs
 
     is_blob_data_test = blob_data is not None
 
@@ -193,7 +190,7 @@ def _append_step(is_blob_data_test, valid=True):
         if is_blob_data_test:
             test_steps.append({
                 'block': get_block_file_name(signed_block),
-                'blobs': None if blobs_root is None else get_blobs_file_name(blobs_root=blobs_root),
+                'blobs': get_blobs_file_name(blobs_root=blobs_root),
                 'proofs': [encode_hex(proof) for proof in blob_data.proofs],
                 'valid': valid,
             })
diff --git a/tests/formats/fork_choice/README.md b/tests/formats/fork_choice/README.md
index 4347e95f2c..d23de865b3 100644
--- a/tests/formats/fork_choice/README.md
+++ b/tests/formats/fork_choice/README.md
@@ -85,9 +85,8 @@ The parameter that is required for executing `on_block(store, block)`.
 {
     block: string           -- the name of the `block_<32-byte-root>.ssz_snappy` file.
                               To execute `on_block(store, block)` with the given attestation.
-    blobs: string or `null` -- optional, the name of the `blobs_<32-byte-root>.ssz_snappy` file.
+    blobs: string           -- optional, the name of the `blobs_<32-byte-root>.ssz_snappy` file.
                                The blobs file content is a `List[Blob, MAX_BLOBS_PER_BLOCK]` SSZ object.
-                               If it's `null`, `blobs` is an empty list.
     proofs: array of byte48 hex string -- optional, the proofs of blob commitments.
     valid: bool             -- optional, default to `true`.
                                If it's `false`, this execution step is expected to be invalid.
@@ -96,7 +95,7 @@ The parameter that is required for executing `on_block(store, block)`.
 
 The file is located in the same folder (see below).
 
-`blobs` and `proofs` are new fields from Deneb EIP-4844. These are the expected values from `retrieve_blobs_and_proofs()` helper inside `is_data_available()` helper.
+`blobs` and `proofs` are new fields from Deneb EIP-4844. These fields indicate the expected values from `retrieve_blobs_and_proofs()` helper inside `is_data_available()` helper. If these two fields are not provided, `retrieve_blobs_and_proofs()` returns empty lists.
 
 After this step, the `store` object may have been updated.