improve comments and add withdrawal reason

proto/cmp/services/cancellation/v1/accept.proto

@@ -17,7 +17,9 @@ message AcceptCancellationRequest {
   // Cancellation token ID
   uint64 token_id = 2;
 
-  // Refund amount to validate the acceptance on-chain
+  // Refund amount that must match the original cancellation proposal for on-chain
+  // validation. The transaction will fail if the amounts don't match. This is used
+  // to prevent front-running attacks.
   cmp.types.v2.Price refund_amount = 3;
 }
 
@@ -26,7 +28,10 @@ message AcceptCancellationResponse {
   // Response header
   cmp.types.v1.ResponseHeader header = 1;
 
-  // Transaction ID on-chain for the cancellation proposal acceptance. This
-  // transaction proves the acceptance of the proposal on-chain to avoid disputes.
+  // Transaction ID on-chain for the cancellation proposal acceptance.
+  // This transaction can be verified on-chain to:
+  // 1. Prove the exact time of acceptance
+  // 2. Validate the accepted refund amount
+  // 3. Prevent disputes about acceptance terms
   string transaction_id = 2;
 }

proto/cmp/services/cancellation/v1/counter.proto

@@ -22,7 +22,10 @@ message CounterCancellationResponse {
   // Response header
   cmp.types.v1.ResponseHeader header = 1;
 
-  // Transaction ID on-chain for the cancellation proposal counter. This transaction
-  // proves the counter of the proposal on-chain to avoid disputes.
+  // Transaction ID on-chain for the cancellation proposal counter.
+  // This transaction can be verified on-chain to:
+  // 1. Prove the exact time of the counter proposal
+  // 2. Validate the counter refund amount
+  // 3. Prevent disputes about counter terms
   string transaction_id = 2;
 }

proto/cmp/services/cancellation/v1/initiate.proto

@@ -25,7 +25,11 @@ message InitiateCancellationResponse {
   cmp.types.v1.ResponseHeader header = 1;
 
   // Transaction ID on-chain for the cancellation proposal initiation. This
-  // transaction proves the initiation of the cancellation proposal on-chain to
-  // avoid disputes.
+  // transaction proves the initiation of the cancellation proposal on-chain.
+  //
+  // This transaction can be verified on-chain to:
+  // 1. Prove the exact time of initiation of the cancellation proposal
+  // 2. Validate the refund amount
+  // 3. Prevent disputes about the cancellation terms
   string transaction_id = 2;
 }

proto/cmp/services/cancellation/v1/reject.proto

@@ -22,7 +22,11 @@ message RejectCancellationResponse {
   // Response Header
   cmp.types.v1.ResponseHeader header = 1;
 
-  // Transaction ID on-chain for the cancellation proposal rejection. This
-  // transaction proves the rejection of the proposal on-chain to avoid disputes.
+  // Transaction ID on-chain for the cancellation proposal rejection.
+  //
+  // This transaction can be verified on-chain to:
+  // 1. Prove the exact time of the rejection
+  // 2. Validate the rejection reason
+  // 3. Prevent disputes about the cancellation
   string transaction_id = 2;
 }

proto/cmp/services/cancellation/v1/withdraw.proto

@@ -2,6 +2,7 @@ syntax = "proto3";
 
 package cmp.services.cancellation.v1;
 
+import "cmp/services/cancellation/v1/reason.proto";
 import "cmp/types/v1/common.proto";
 
 // Request for withdrawal of an active cancellation proposal
@@ -11,15 +12,21 @@ message WithdrawCancellationRequest {
 
   // Cancellation token ID
   uint64 token_id = 2;
+
+  // Withdrawal reason
+  cmp.services.cancellation.v1.WithdrawalReason reason = 3;
 }
 
 // Response for withdrawal of an active cancellation proposal
 message WithdrawCancellationResponse {
   // Response header
   cmp.types.v1.ResponseHeader header = 1;
 
-  // Transaction ID on-chain for withdrawing the cancellation proposal. This
-  // transaction proves the withdrawal of the cancellation proposal on-chain to
-  // avoid disputes.
+  // Transaction ID on-chain for withdrawing the cancellation proposal.
+  //
+  // This transaction can be verified on-chain to:
+  // 1. Prove the exact time of withdrawal
+  // 2. Validate the accepted refund amount
+  // 3. Prevent disputes about acceptance terms
   string transaction_id = 2;
 }