diff --git a/packages/validator/src/services/attestation.ts b/packages/validator/src/services/attestation.ts
index 892b9a6b22bf..e2b8d61bdff5 100644
--- a/packages/validator/src/services/attestation.ts
+++ b/packages/validator/src/services/attestation.ts
@@ -166,7 +166,10 @@ export class AttestationService {
 
     await Promise.all(
       duties.map(async ({duty}) => {
+        // TODO:  duty <> attestation consistency check required? slot and index are checked by lighthouse
+        // see https://github.com/sigp/lighthouse/blob/319cc61afeb1dbf3692e280dfa18e7b455542b16/validator_client/src/attestation_service.rs#L367
         const index = duty.committeeIndex;
+        // TODO: mutating is not required if attestation grouping is disabled as actual committee index is already set
         const attestationData: phase0.AttestationData = {...attestationNoCommittee, index};
         const logCtxValidator = {slot, index, head: headRootHex, validatorIndex: duty.validatorIndex};