diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index 75fa127f7..441d6f72b 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -653,7 +653,7 @@ def is_slashable_attestation_data(data_1: AttestationData, data_2: AttestationDa
 ```python
 def is_valid_indexed_attestation(state: BeaconState, indexed_attestation: IndexedAttestation) -> bool:
     """
-    Check indices and signature of ``indexed_attestation``.
+    Check if ``indexed_attestation`` has valid indices and signature.
     """
     bit_0_indices = indexed_attestation.custody_bit_0_indices
     bit_1_indices = indexed_attestation.custody_bit_1_indices