fix: derive Nexus EIP-712 domain version fallback from MEE version

src/sdk/account/utils/Constants.ts

@@ -107,6 +107,20 @@ export const MOCK_MULTI_MODULE_ADDRESS =
 export const MODULE_TYPE_MULTI = 0
 
 export const NEXUS_DOMAIN_NAME = "Nexus"
+
+/**
+ * Legacy fallback for the Nexus EIP-712 domain version. Only correct for MEE
+ * versions backed by Nexus 1.2.0 (e.g. V2_0_0, V2_1_0). For MEE ≥ V2_2_0 the
+ * domain version moved to the 1.3.x line and this constant produces signatures
+ * that the on-chain Nexus contract rejects.
+ *
+ * Prefer `getNexusDomainVersion(meeVersion)` from `../../constants` whenever
+ * the MEE version is known — or `getEip712Domain()` to query the deployed
+ * contract directly. This constant is kept only as a back-compat default and
+ * may be removed in a future major release.
+ *
+ * @deprecated Use `getNexusDomainVersion(meeVersionOrConfig)` instead.
+ */
 export const NEXUS_DOMAIN_VERSION = "1.2.0"
 export const NEXUS_DOMAIN_TYPEHASH =
   "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"

src/sdk/account/utils/Utils.ts

@@ -38,7 +38,8 @@ import {
   NEXUS_DOMAIN_TYPEHASH,
   NEXUS_DOMAIN_VERSION
 } from "../../account/utils/Constants"
-import { MEEVersion } from "../../constants"
+import { MEEVersion, getNexusDomainVersion } from "../../constants"
+import type { MEEVersionConfig } from "./getVersion"
 import { EIP1271Abi } from "../../constants/abi"
 import {
   type AnyData,
@@ -286,8 +287,12 @@ export function convertToFactor(percentage: number | undefined): number {
  *
  * @param accountOwner - The account owner address
  * @param modules - Array of modules with their types and configurations
- * @param domainName - Optional domain name
- * @param domainVersion - Optional domain version
+ * @param domainName - Optional domain name. Defaults to `NEXUS_DOMAIN_NAME`.
+ * @param domainVersion - Optional domain version. **Defaults to the legacy
+ *   `NEXUS_DOMAIN_VERSION` ("1.2.0"), which is wrong for any MEE ≥ V2_2_0.**
+ *   Callers should pass `getNexusDomainVersion(meeVersionOrConfig)` whenever
+ *   the MEE version is known so the install-mode signature is verifiable on
+ *   the Nexus 1.3.x line.
  * @returns Tuple of [installData, hash]
  */
 export function makeInstallDataAndHash(
@@ -382,13 +387,26 @@ export function getTypesForEIP712Domain({
 /**
  * Retrieves account metadata including name, version, and chain ID.
  *
+ * Tries `eip712Domain()` on-chain first. If the SCA is not yet deployed
+ * (counterfactual) or the call fails for any reason, falls back to the static
+ * domain name + version. When `meeVersionOrConfig` is supplied, the fallback
+ * version is derived from that config's `accountId` (e.g. MEE v2.2.2 →
+ * `"1.3.2"`); otherwise it falls back to the legacy `NEXUS_DOMAIN_VERSION`
+ * constant, which only reflects Nexus 1.2.0 and is wrong for any MEE ≥ 2.2.x.
+ * Pass `meeVersionOrConfig` whenever you know which MEE version the account
+ * is being used with.
+ *
  * @param client - The viem Client instance
  * @param accountAddress - The account address to query
+ * @param meeVersionOrConfig - Optional MEE version (or resolved config) used
+ *   to derive the correct fallback domain version. Strongly recommended when
+ *   the account may not yet be deployed.
  * @returns Promise resolving to account metadata
  */
 export const getAccountMeta = async (
   client: Client,
-  accountAddress: Address
+  accountAddress: Address,
+  meeVersionOrConfig?: MEEVersion | MEEVersionConfig
 ): Promise<AccountMetadata> => {
   try {
     const domain = await client.request({
@@ -420,7 +438,9 @@ export const getAccountMeta = async (
   } catch (error) {}
   return {
     name: NEXUS_DOMAIN_NAME,
-    version: NEXUS_DOMAIN_VERSION,
+    version: meeVersionOrConfig
+      ? getNexusDomainVersion(meeVersionOrConfig)
+      : NEXUS_DOMAIN_VERSION,
     chainId: client.chain
       ? BigInt(client.chain.id)
       : BigInt(await client.extend(publicActions).getChainId())

src/sdk/constants/index.ts

@@ -187,6 +187,44 @@ export const DEFAULT_CONFIGURATIONS_BY_MEE_VERSION: Record<
   }
 }
 
+/**
+ * The Nexus EIP-712 domain version string for a given MEE version (or its
+ * already-resolved config).
+ *
+ * Each `MEEVersionConfig.accountId` is formatted as `biconomy.nexus.<X.Y.Z>` —
+ * the same string the on-chain Nexus contract returns from
+ * `_domainNameAndVersion()`. This helper strips the prefix and returns the
+ * version suffix, giving callers a reliable fallback when an on-chain
+ * `eip712Domain()` query is unavailable (e.g. for a counterfactual SCA whose
+ * factory hasn't been deployed yet).
+ *
+ * @example
+ * getNexusDomainVersion(MEEVersion.V2_2_2)         // → "1.3.2"
+ * getNexusDomainVersion(getMEEVersion(MEEVersion.V2_1_0)) // → "1.2.0"
+ */
+export const getNexusDomainVersion = (
+  meeVersionOrConfig: MEEVersion | MEEVersionConfig
+): string => {
+  const config =
+    typeof meeVersionOrConfig === "string"
+      ? DEFAULT_CONFIGURATIONS_BY_MEE_VERSION[meeVersionOrConfig]
+      : meeVersionOrConfig
+  if (!config) {
+    throw new Error(
+      `Unsupported MEE version: ${String(meeVersionOrConfig)}. ` +
+        `Expected one of: ${Object.keys(DEFAULT_CONFIGURATIONS_BY_MEE_VERSION).join(", ")}`
+    )
+  }
+  const prefix = "biconomy.nexus."
+  if (!config.accountId.startsWith(prefix)) {
+    throw new Error(
+      `Unexpected accountId format: "${config.accountId}". ` +
+        `Expected "${prefix}<X.Y.Z>".`
+    )
+  }
+  return config.accountId.slice(prefix.length)
+}
+
 // Rhinestone constants
 export {
   SMART_SESSIONS_ADDRESS,