diff --git a/zkevm-circuits/src/root_circuit/aggregation.rs b/zkevm-circuits/src/root_circuit/aggregation.rs
index 2c078013e32..bb9162a88b4 100644
--- a/zkevm-circuits/src/root_circuit/aggregation.rs
+++ b/zkevm-circuits/src/root_circuit/aggregation.rs
@@ -252,6 +252,8 @@ impl AggregationConfig {
 
                 // Verify the cheap part and get accumulator (left-hand and right-hand side of
                 // pairing) of individual proof.
+                // TODO need to retrieved loaded ec point for rw_table column witness
+                // which will be used to compute poseidon script
                 let (instances, accumulators) = snarks
                     .iter()
                     .map(|snark| {
@@ -272,7 +274,24 @@ impl AggregationConfig {
                     })
                     .collect_vec()
                     .into_iter()
-                    .unzip::<_, _, Vec<_>, Vec<_>>();
+                    .unzip::<_, _, Vec<_>, Vec<_>>(); // TODO remove `unzip` to keep the raw instances structure from different snark
+                                                      // proof
+
+                // TODO 1. process raw instances from all snarks into 2 collections: {public input
+                // instances} and {chunk consistency instances} 1st snark {public
+                // input instance} and last snark {public input instance} should be concat into
+                // final instances, whereas {chunk consistency instances} will be
+                // converted to witness, and constraints it equality between i and i+1 snark.
+                // since they are loaded field, consistency can encoded into circuit by simply
+                // taking 2 loaded field a, b and then `a - b = 0`, which will be
+                // reflected into the plonk circuit
+
+                // TODO 2. get all column commitment loaded ec points (witness of rw_table from all
+                // snark proof, then absorb them into fresh transcript to squeeze to
+                // get challenge alpha', following by absorb alpha' and squeeze to get challenge
+                // gamma'. At the end, constraint alpha', gamma' field value equal to alpha,
+                // gamma appear at public input instances by simply invoke loaded field value
+                // equality: `alpha' - alpha = 0` and `gamma' - gamma = 0`
 
                 // Verify proof for accumulation of all accumulators into new one.
                 let accumulator = {