From a20fac086e290723933765bf72b633edd0285e7b Mon Sep 17 00:00:00 2001
From: Arseniy Klempner <arseniyk@status.im>
Date: Mon, 15 Dec 2025 19:40:27 -0800
Subject: [PATCH] fix: remove unused index param

---
 packages/rln/src/proof.spec.ts | 1 -
 packages/rln/src/zerokit.ts    | 7 +++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/packages/rln/src/proof.spec.ts b/packages/rln/src/proof.spec.ts
index 61b084e617..6a1499db86 100644
--- a/packages/rln/src/proof.spec.ts
+++ b/packages/rln/src/proof.spec.ts
@@ -71,7 +71,6 @@ describe("RLN Proof Integration Tests", function () {
 
     const proof = await rlnInstance.zerokit.generateRLNProof(
       testMessage,
-      Number(membershipIndex),
       new Date(),
       credential.identity.IDSecretHash,
       merkleProof.map((element) =>
diff --git a/packages/rln/src/zerokit.ts b/packages/rln/src/zerokit.ts
index e82a9089c2..d39aebde85 100644
--- a/packages/rln/src/zerokit.ts
+++ b/packages/rln/src/zerokit.ts
@@ -7,6 +7,7 @@ import { WitnessCalculator } from "./resources/witness_calculator";
 import { BytesUtils } from "./utils/bytes.js";
 import { dateToEpoch, epochIntToBytes } from "./utils/epoch.js";
 import { poseidonHash, sha256 } from "./utils/hash.js";
+import { MERKLE_TREE_DEPTH } from "./utils/merkle.js";
 
 export class Zerokit {
   public constructor(
@@ -83,7 +84,6 @@ export class Zerokit {
 
   public async generateRLNProof(
     msg: Uint8Array,
-    index: number, // index of the leaf in the merkle tree
     epoch: Uint8Array | Date | undefined,
     idSecretHash: Uint8Array,
     pathElements: Uint8Array[],
@@ -103,7 +103,10 @@ export class Zerokit {
       throw new Error(
         `ID secret hash must be 32 bytes, got ${idSecretHash.length}`
       );
-    if (index < 0) throw new Error("index must be >= 0");
+    if (pathElements.length !== MERKLE_TREE_DEPTH)
+      throw new Error(`Path elements must be ${MERKLE_TREE_DEPTH} bytes`);
+    if (identityPathIndex.length !== MERKLE_TREE_DEPTH)
+      throw new Error(`Identity path index must be ${MERKLE_TREE_DEPTH} bytes`);
     if (
       rateLimit < RATE_LIMIT_PARAMS.MIN_RATE ||
       rateLimit > RATE_LIMIT_PARAMS.MAX_RATE