diff --git a/e2e/README.md b/e2e/README.md
index bc4f44dfd7..c854f1a1fd 100644
--- a/e2e/README.md
+++ b/e2e/README.md
@@ -86,6 +86,26 @@ Add the `-v` flag to any command for verbose output:
 
 Useful for debugging test failures or understanding the payment flow.
 
+### Targeting a Specific EVM Chain
+
+The harness defaults to Base Sepolia (`eip155:84532`) on `--testnet`. Pass
+`--evm-network=<caip2>` to target any chain in the SDK's `DEFAULT_STABLECOINS`
+catalog (`typescript/packages/mechanisms/evm/src/shared/defaultAssets.ts`).
+Combine with `--families=evm` to skip non-EVM credential requirements.
+
+```bash
+# Run EVM-only against Mezo Testnet
+pnpm test --testnet --families=evm --evm-network=eip155:31611
+```
+
+The harness derives its chain registry from `DEFAULT_STABLECOINS` at module load.
+Adding a new chain to the SDK propagates here after `pnpm install` — no harness
+source edit. Display names come from viem's chain database.
+
+EVM-only runs (`--families=evm`) do NOT require Solana, Aptos, Hedera, or
+Stellar credentials — the corresponding env vars are only consulted when their
+family is selected.
+
 ## Wallet Safety Warning
 
 **Use dedicated test wallets only. Do NOT use wallets that hold real funds.**
@@ -153,6 +173,14 @@ TONAPI_API_KEY=<tonapi-key> \
 pnpm test --testnet --families=tvm --facilitators=python --clients=httpx,requests --servers=fastapi,flask --min -v
 ```
 
+Optional environment variables (chain selection):
+
+```bash
+EVM_RPC_URL=https://...              # Override the EVM RPC URL for the selected
+                                      # chain. When unset, the harness uses
+                                      # viem's default RPC for the chain.
+```
+
 Optional environment variables (batch-settlement scheme):
 
 ```bash
diff --git a/e2e/clients/axios/index.ts b/e2e/clients/axios/index.ts
index 5b16a67e9f..45031ab092 100644
--- a/e2e/clients/axios/index.ts
+++ b/e2e/clients/axios/index.ts
@@ -1,9 +1,9 @@
 import { config } from "dotenv";
 import axios from "axios";
 import { wrapAxiosWithPayment, decodePaymentResponseHeader } from "@x402/axios";
-import { createPublicClient, http } from "viem";
+import { createPublicClient, defineChain, http, type Chain } from "viem";
 import { privateKeyToAccount } from "viem/accounts";
-import { base, baseSepolia } from "viem/chains";
+import * as allViemChains from "viem/chains";
 import { ExactEvmScheme, type ExactEvmSchemeOptions } from "@x402/evm/exact/client";
 import {
   UptoEvmScheme as UptoEvmClientScheme,
@@ -32,13 +32,39 @@ const baseURL = process.env.RESOURCE_SERVER_URL as string;
 const endpointPath = process.env.ENDPOINT_PATH as string;
 const url = `${baseURL}${endpointPath}`;
 const evmAccount = privateKeyToAccount(process.env.EVM_PRIVATE_KEY as `0x${string}`);
-const svmSigner = await createKeyPairSignerFromBytes(
-  base58.decode(process.env.SVM_PRIVATE_KEY as string),
-);
+// Lazy SVM signer: only decoded when SVM_PRIVATE_KEY is set so EVM-only runs
+// (e.g. --families=evm) don't require a Solana key.
+const svmSigner = process.env.SVM_PRIVATE_KEY
+  ? await createKeyPairSignerFromBytes(
+      base58.decode(process.env.SVM_PRIVATE_KEY),
+    )
+  : undefined;
 
 const evmNetwork = process.env.EVM_NETWORK || "eip155:84532";
 const evmRpcUrl = process.env.EVM_RPC_URL;
-const evmChain = evmNetwork === "eip155:8453" ? base : baseSepolia;
+// Resolve any CAIP-2 EVM chain — viem's chain database first, with a
+// minimal defineChain fallback for any SDK chain that viem hasn't packaged yet.
+function resolveEvmChain(network: string): Chain {
+  const [namespace, ref] = network.split(":");
+  if (namespace !== "eip155") {
+    throw new Error(`resolveEvmChain: not an EVM network: ${network}`);
+  }
+  const chainId = Number(ref);
+  if (!Number.isInteger(chainId) || chainId <= 0) {
+    throw new Error(`resolveEvmChain: invalid EVM chain id in ${network}`);
+  }
+  const known = (Object.values(allViemChains) as Chain[]).find(
+    (c) => c && typeof c === "object" && c.id === chainId,
+  );
+  if (known) return known;
+  return defineChain({
+    id: chainId,
+    name: `EVM ${chainId}`,
+    nativeCurrency: { name: "Ether", symbol: "ETH", decimals: 18 },
+    rpcUrls: { default: { http: [] } },
+  });
+}
+const evmChain = resolveEvmChain(evmNetwork);
 
 const publicClient = createPublicClient({
   chain: evmChain,
@@ -113,10 +139,13 @@ const client = new x402Client()
   .register("eip155:*", new UptoEvmClientScheme(evmSigner, uptoSchemeOptions))
   .register("eip155:*", batchSettlementScheme)
   .registerV1("base-sepolia", new ExactEvmSchemeV1(evmSigner))
-  .registerV1("base", new ExactEvmSchemeV1(evmSigner))
-  .register("solana:*", new ExactSvmScheme(svmSigner))
-  .registerV1("solana-devnet", new ExactSvmSchemeV1(svmSigner))
-  .registerV1("solana", new ExactSvmSchemeV1(svmSigner));
+  .registerV1("base", new ExactEvmSchemeV1(evmSigner));
+if (svmSigner) {
+  client
+    .register("solana:*", new ExactSvmScheme(svmSigner))
+    .registerV1("solana-devnet", new ExactSvmSchemeV1(svmSigner))
+    .registerV1("solana", new ExactSvmSchemeV1(svmSigner));
+}
 if (aptosAccount) {
   client.register("aptos:*", new ExactAptosScheme(aptosAccount));
 }
diff --git a/e2e/clients/fetch/index.ts b/e2e/clients/fetch/index.ts
index da3164a42f..5da5bbdcf4 100644
--- a/e2e/clients/fetch/index.ts
+++ b/e2e/clients/fetch/index.ts
@@ -1,8 +1,8 @@
 import { config } from "dotenv";
 import { wrapFetchWithPayment } from "@x402/fetch";
-import { createPublicClient, http } from "viem";
+import { createPublicClient, defineChain, http, type Chain } from "viem";
 import { privateKeyToAccount } from "viem/accounts";
-import { base, baseSepolia } from "viem/chains";
+import * as allViemChains from "viem/chains";
 import { ExactEvmScheme, type ExactEvmSchemeOptions } from "@x402/evm/exact/client";
 import {
   UptoEvmScheme as UptoEvmClientScheme,
@@ -31,13 +31,39 @@ const baseURL = process.env.RESOURCE_SERVER_URL as string;
 const endpointPath = process.env.ENDPOINT_PATH as string;
 const url = `${baseURL}${endpointPath}`;
 const evmAccount = privateKeyToAccount(process.env.EVM_PRIVATE_KEY as `0x${string}`);
-const svmSigner = await createKeyPairSignerFromBytes(
-  base58.decode(process.env.SVM_PRIVATE_KEY as string),
-);
+// Lazy SVM signer: only decoded when SVM_PRIVATE_KEY is set so EVM-only runs
+// (e.g. --families=evm) don't require a Solana key.
+const svmSigner = process.env.SVM_PRIVATE_KEY
+  ? await createKeyPairSignerFromBytes(
+      base58.decode(process.env.SVM_PRIVATE_KEY),
+    )
+  : undefined;
 
 const evmNetwork = process.env.EVM_NETWORK || "eip155:84532";
 const evmRpcUrl = process.env.EVM_RPC_URL;
-const evmChain = evmNetwork === "eip155:8453" ? base : baseSepolia;
+// Resolve any CAIP-2 EVM chain — viem's chain database first, with a
+// minimal defineChain fallback for any SDK chain that viem hasn't packaged yet.
+function resolveEvmChain(network: string): Chain {
+  const [namespace, ref] = network.split(":");
+  if (namespace !== "eip155") {
+    throw new Error(`resolveEvmChain: not an EVM network: ${network}`);
+  }
+  const chainId = Number(ref);
+  if (!Number.isInteger(chainId) || chainId <= 0) {
+    throw new Error(`resolveEvmChain: invalid EVM chain id in ${network}`);
+  }
+  const known = (Object.values(allViemChains) as Chain[]).find(
+    (c) => c && typeof c === "object" && c.id === chainId,
+  );
+  if (known) return known;
+  return defineChain({
+    id: chainId,
+    name: `EVM ${chainId}`,
+    nativeCurrency: { name: "Ether", symbol: "ETH", decimals: 18 },
+    rpcUrls: { default: { http: [] } },
+  });
+}
+const evmChain = resolveEvmChain(evmNetwork);
 
 const publicClient = createPublicClient({
   chain: evmChain,
@@ -112,10 +138,13 @@ const client = new x402Client()
   .register("eip155:*", new UptoEvmClientScheme(evmSigner, uptoSchemeOptions))
   .register("eip155:*", batchSettlementScheme)
   .registerV1("base-sepolia", new ExactEvmSchemeV1(evmSigner))
-  .registerV1("base", new ExactEvmSchemeV1(evmSigner))
-  .register("solana:*", new ExactSvmScheme(svmSigner))
-  .registerV1("solana-devnet", new ExactSvmSchemeV1(svmSigner))
-  .registerV1("solana", new ExactSvmSchemeV1(svmSigner));
+  .registerV1("base", new ExactEvmSchemeV1(evmSigner));
+if (svmSigner) {
+  client
+    .register("solana:*", new ExactSvmScheme(svmSigner))
+    .registerV1("solana-devnet", new ExactSvmSchemeV1(svmSigner))
+    .registerV1("solana", new ExactSvmSchemeV1(svmSigner));
+}
 if (aptosAccount) {
   client.register("aptos:*", new ExactAptosScheme(aptosAccount));
 }
diff --git a/e2e/clients/mcp-typescript/index.ts b/e2e/clients/mcp-typescript/index.ts
index eb832cf0c4..21c914458c 100644
--- a/e2e/clients/mcp-typescript/index.ts
+++ b/e2e/clients/mcp-typescript/index.ts
@@ -39,7 +39,7 @@ interface RequestResult {
 const serverUrl = process.env.RESOURCE_SERVER_URL as string;
 const endpointPath = process.env.ENDPOINT_PATH as string; // tool name, e.g. "get_weather"
 const evmPrivateKey = process.env.EVM_PRIVATE_KEY as `0x${string}`;
-const evmNetwork = process.env.EVM_NETWORK || "eip155:84532";
+const evmNetwork = (process.env.EVM_NETWORK || "eip155:84532") as `${string}:${string}`;
 const evmChain = evmNetwork === "eip155:8453" ? base : baseSepolia;
 const channelSalt = process.env.CHANNEL_SALT as `0x${string}` | undefined;
 const batchSettlementPhase = process.env.BATCH_SETTLEMENT_PHASE as
diff --git a/e2e/facilitators/typescript/index.ts b/e2e/facilitators/typescript/index.ts
index e714cbeb1c..75b3276c3e 100644
--- a/e2e/facilitators/typescript/index.ts
+++ b/e2e/facilitators/typescript/index.ts
@@ -66,6 +66,7 @@ import dotenv from "dotenv";
 import express from "express";
 import {
   createWalletClient,
+  defineChain,
   http,
   nonceManager,
   publicActions,
@@ -74,7 +75,7 @@ import {
   recoverTransactionAddress,
 } from "viem";
 import { privateKeyToAccount } from "viem/accounts";
-import { baseSepolia, base } from "viem/chains";
+import * as allViemChains from "viem/chains";
 import { BazaarCatalog } from "./bazaar.js";
 
 dotenv.config();
@@ -97,15 +98,29 @@ const APTOS_RPC_URL = process.env.APTOS_RPC_URL;
 const HEDERA_NODE_URL = process.env.HEDERA_NODE_URL;
 const STELLAR_RPC_URL = process.env.STELLAR_RPC_URL;
 
-// Map CAIP-2 network IDs to viem chains
+// Resolve a CAIP-2 EVM network id to a viem `Chain`.
+// Uses viem's chain database when available; falls back to a minimal
+// defineChain so any SDK chain viem hasn't packaged yet still works
+// when the caller supplies their own RPC URL.
 function getEvmChain(network: string): Chain {
-  switch (network) {
-    case "eip155:8453":
-      return base;
-    case "eip155:84532":
-    default:
-      return baseSepolia;
+  const [namespace, ref] = network.split(":");
+  if (namespace !== "eip155") {
+    throw new Error(`getEvmChain: not an EVM network: ${network}`);
   }
+  const chainId = Number(ref);
+  if (!Number.isInteger(chainId) || chainId <= 0) {
+    throw new Error(`getEvmChain: invalid EVM chain id in ${network}`);
+  }
+  const known = (Object.values(allViemChains) as Chain[]).find(
+    (c) => c && typeof c === "object" && c.id === chainId,
+  );
+  if (known) return known;
+  return defineChain({
+    id: chainId,
+    name: `EVM ${chainId}`,
+    nativeCurrency: { name: "Ether", symbol: "ETH", decimals: 18 },
+    rpcUrls: { default: { http: [] } },
+  });
 }
 
 console.log(`🌐 EVM Network: ${EVM_NETWORK}`);
@@ -127,11 +142,6 @@ if (!process.env.EVM_PRIVATE_KEY) {
   process.exit(1);
 }
 
-if (!process.env.SVM_PRIVATE_KEY) {
-  console.error("❌ SVM_PRIVATE_KEY environment variable is required");
-  process.exit(1);
-}
-
 // Initialize the EVM account from private key
 const evmAccount = privateKeyToAccount(
   process.env.EVM_PRIVATE_KEY as `0x${string}`,
@@ -154,11 +164,17 @@ const authorizerSigner: AuthorizerSigner = {
 };
 console.info(`EVM Receiver Authorizer: ${authorizerSigner.address}`);
 
-// Initialize the SVM account from private key
-const svmAccount = await createKeyPairSignerFromBytes(
-  base58.decode(process.env.SVM_PRIVATE_KEY as string),
-);
-console.info(`SVM Facilitator account: ${svmAccount.address}`);
+// Initialize the SVM account from private key (optional)
+// Lazy-decoded so EVM-only runs (e.g. --families=evm) don't require an SVM key.
+let svmAccount:
+  | Awaited<ReturnType<typeof createKeyPairSignerFromBytes>>
+  | undefined;
+if (process.env.SVM_PRIVATE_KEY) {
+  svmAccount = await createKeyPairSignerFromBytes(
+    base58.decode(process.env.SVM_PRIVATE_KEY as string),
+  );
+  console.info(`SVM Facilitator account: ${svmAccount.address}`);
+}
 
 // Initialize the Aptos account from private key (format to AIP-80 compliant format) if provided
 let aptosAccount: Account | undefined;
@@ -266,11 +282,13 @@ const evmSigner = toFacilitatorEvmSigner({
 });
 
 // Facilitator can now handle all Solana networks with automatic RPC creation
-// Pass custom RPC URL if provided
-const svmSigner = toFacilitatorSvmSigner(
-  svmAccount,
-  SVM_RPC_URL ? { defaultRpcUrl: SVM_RPC_URL } : undefined,
-);
+// Pass custom RPC URL if provided. Skipped when no SVM key is configured.
+const svmSigner = svmAccount
+  ? toFacilitatorSvmSigner(
+      svmAccount,
+      SVM_RPC_URL ? { defaultRpcUrl: SVM_RPC_URL } : undefined,
+    )
+  : undefined;
 
 // Facilitator can handle all Aptos networks with automatic RPC creation
 // Pass custom RPC URL if provided
@@ -422,9 +440,12 @@ facilitator
     EVM_NETWORK as Network,
     new BatchSettlementEvmScheme(evmSigner, authorizerSigner),
   )
-  .registerV1(EVM_V1_NETWORKS as Network[], new ExactEvmSchemeV1(evmSigner))
-  .register(SVM_NETWORK as Network, new ExactSvmScheme(svmSigner))
-  .registerV1(SVM_V1_NETWORKS as Network[], new ExactSvmSchemeV1(svmSigner));
+  .registerV1(EVM_V1_NETWORKS as Network[], new ExactEvmSchemeV1(evmSigner));
+if (svmSigner) {
+  facilitator
+    .register(SVM_NETWORK as Network, new ExactSvmScheme(svmSigner))
+    .registerV1(SVM_V1_NETWORKS as Network[], new ExactSvmSchemeV1(svmSigner));
+}
 if (avmSigner) {
   facilitator.register(AVM_NETWORK as Network, new ExactAvmScheme(avmSigner));
 }
@@ -756,7 +777,7 @@ app.get("/health", (req, res) => {
   res.json({
     status: "ok",
     evmNetwork: EVM_NETWORK,
-    svmNetwork: SVM_NETWORK,
+    svmNetwork: svmSigner ? SVM_NETWORK : "(not configured)",
     avmNetwork: avmSigner ? AVM_NETWORK : "(not configured)",
     aptosNetwork: aptosAccount ? APTOS_NETWORK : "(not configured)",
     hederaNetwork: hederaSigner ? HEDERA_NETWORK : "(not configured)",
diff --git a/e2e/mock-facilitator/index.ts b/e2e/mock-facilitator/index.ts
index 024cdd896f..04ba2324b8 100644
--- a/e2e/mock-facilitator/index.ts
+++ b/e2e/mock-facilitator/index.ts
@@ -12,9 +12,9 @@ import http from "node:http";
 
 const PORT = parseInt(process.env.PORT || "4099", 10);
 const EVM_NETWORK = process.env.EVM_NETWORK || "eip155:84532";
-const SVM_NETWORK = process.env.SVM_NETWORK || "solana:EtWTRABZaYq6iMfeYKouRu166VU2xqa1";
-const APTOS_NETWORK = process.env.APTOS_NETWORK || "aptos:2";
-const STELLAR_NETWORK = process.env.STELLAR_NETWORK || "stellar:testnet";
+const SVM_NETWORK = process.env.SVM_NETWORK;
+const APTOS_NETWORK = process.env.APTOS_NETWORK;
+const STELLAR_NETWORK = process.env.STELLAR_NETWORK;
 
 const DUMMY_EVM_SIGNER = "0x0000000000000000000000000000000000000001";
 const DUMMY_SVM_SIGNER = "11111111111111111111111111111111";
@@ -23,7 +23,7 @@ const DUMMY_APTOS_SIGNER =
 const DUMMY_STELLAR_SIGNER = "GAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAWHF";
 
 function buildSupportedResponse() {
-  const evmSchemes = ["exact", "upto"];
+  const evmSchemes = ["exact", "upto", "batch-settlement"];
   const otherSchemes = ["exact"];
   const versions = [1, 2];
 
@@ -37,8 +37,10 @@ function buildSupportedResponse() {
     for (const scheme of evmSchemes) {
       kinds.push({ x402Version: version, scheme, network: EVM_NETWORK });
     }
-    for (const scheme of otherSchemes) {
-      kinds.push({ x402Version: version, scheme, network: SVM_NETWORK });
+    if (SVM_NETWORK) {
+      for (const scheme of otherSchemes) {
+        kinds.push({ x402Version: version, scheme, network: SVM_NETWORK });
+      }
     }
     if (APTOS_NETWORK) {
       for (const scheme of otherSchemes) {
@@ -54,8 +56,10 @@ function buildSupportedResponse() {
 
   const signers: Record<string, string[]> = {
     "eip155:*": [DUMMY_EVM_SIGNER],
-    "solana:*": [DUMMY_SVM_SIGNER],
   };
+  if (SVM_NETWORK) {
+    signers["solana:*"] = [DUMMY_SVM_SIGNER];
+  }
   if (APTOS_NETWORK) {
     signers["aptos:*"] = [DUMMY_APTOS_SIGNER];
   }
diff --git a/e2e/package.json b/e2e/package.json
index 00a5b7ff86..6e46df2ede 100644
--- a/e2e/package.json
+++ b/e2e/package.json
@@ -17,6 +17,7 @@
     "permit2:revoke": "tsx scripts/permit2-approval.ts revoke"
   },
   "dependencies": {
+    "@x402/evm": "workspace:*",
     "dotenv": "^17.0.1",
     "prompts": "^2.4.2",
     "tsx": "^4.21.0",
diff --git a/e2e/pnpm-lock.yaml b/e2e/pnpm-lock.yaml
index 91def4e6a6..01c2ee200d 100644
--- a/e2e/pnpm-lock.yaml
+++ b/e2e/pnpm-lock.yaml
@@ -8,6 +8,9 @@ importers:
 
   .:
     dependencies:
+      '@x402/evm':
+        specifier: workspace:*
+        version: link:../typescript/packages/mechanisms/evm
       dotenv:
         specifier: ^17.0.1
         version: 17.0.1
diff --git a/e2e/scripts/permit2-approval.ts b/e2e/scripts/permit2-approval.ts
index 9e3ef2e6f0..107476a418 100644
--- a/e2e/scripts/permit2-approval.ts
+++ b/e2e/scripts/permit2-approval.ts
@@ -18,13 +18,16 @@ import { config } from 'dotenv';
 import {
   createWalletClient,
   createPublicClient,
+  defineChain,
   http,
   parseAbi,
   formatUnits,
   getAddress,
+  type Chain,
 } from 'viem';
 import { privateKeyToAccount } from 'viem/accounts';
-import { base, baseSepolia } from 'viem/chains';
+import * as allViemChains from 'viem/chains';
+import { DEFAULT_STABLECOINS } from '@x402/evm';
 
 config();
 
@@ -33,41 +36,58 @@ const PERMIT2_ADDRESS = '0x000000000022D473030F116dDEE9F6B43aC78BA3';
 
 const evmNetwork = process.env.EVM_NETWORK || 'eip155:84532';
 const evmRpcUrl = process.env.EVM_RPC_URL;
-const evmChain = evmNetwork === 'eip155:8453' ? base : baseSepolia;
-const isMainnet = evmNetwork === 'eip155:8453';
-
-const TOKENS_BY_NETWORK: Record<string, Record<string, { address: `0x${string}`; decimals: number; name: string }>> = {
-  'eip155:84532': {
-    USDC: {
-      address: '0x036CbD53842c5426634e7929541eC2318f3dCF7e',
-      decimals: 6,
-      name: 'USDC',
-    },
-    MockERC20: {
-      address: '0xeED520980fC7C7B4eB379B96d61CEdea2423005a',
-      decimals: 6,
-      name: 'MockERC20',
-    },
-  },
-  'eip155:8453': {
-    USDC: {
-      address: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
-      decimals: 6,
-      name: 'USDC',
-    },
-  },
-};
-
-const TOKENS = TOKENS_BY_NETWORK[evmNetwork] || TOKENS_BY_NETWORK['eip155:84532'];
+
+// Resolve any CAIP-2 EVM chain — viem's chain database first, with a
+// minimal defineChain fallback for any SDK chain that viem hasn't packaged yet.
+function resolveEvmChain(network: string): Chain {
+  const [namespace, ref] = network.split(':');
+  if (namespace !== 'eip155') {
+    throw new Error(`resolveEvmChain: not an EVM network: ${network}`);
+  }
+  const chainId = Number(ref);
+  if (!Number.isInteger(chainId) || chainId <= 0) {
+    throw new Error(`resolveEvmChain: invalid EVM chain id in ${network}`);
+  }
+  const known = (Object.values(allViemChains) as Chain[]).find(
+    (c) => c && typeof c === 'object' && c.id === chainId,
+  );
+  if (known) return known;
+  return defineChain({
+    id: chainId,
+    name: `EVM ${chainId}`,
+    nativeCurrency: { name: 'Ether', symbol: 'ETH', decimals: 18 },
+    rpcUrls: { default: { http: [] } },
+  });
+}
+const evmChain = resolveEvmChain(evmNetwork);
+
+// Token list is driven by EVM_PERMIT2_ASSET (canonical Permit2 target for the
+// configured chain). Pass an explicit `[tokenAddress]` CLI arg to operate on a
+// non-default token (e.g. MockERC20 on Base Sepolia).
+//
+// Decimals + display name flow from `DEFAULT_STABLECOINS[evmNetwork]` when the
+// chain is in the SDK's catalog (the canonical case). Custom tokens supplied
+// via the CLI override read decimals from the contract's `decimals()` view.
+const permit2AssetEnv = process.env.EVM_PERMIT2_ASSET;
+const sdkAsset = DEFAULT_STABLECOINS[evmNetwork];
+const TOKENS: Record<string, { address: `0x${string}`; decimals: number; name: string }> = {};
+if (permit2AssetEnv) {
+  TOKENS.PRIMARY = {
+    address: getAddress(permit2AssetEnv) as `0x${string}`,
+    decimals: sdkAsset?.decimals ?? 6,
+    name: sdkAsset?.name ?? 'TOKEN',
+  };
+}
 
 // Maximum uint256 for unlimited approval
 const MAX_UINT256 = 2n ** 256n - 1n;
 
-// ERC20 ABI for approve and allowance
+// ERC20 ABI for approve, allowance, balanceOf, and decimals
 const erc20Abi = parseAbi([
   'function approve(address spender, uint256 amount) returns (bool)',
   'function allowance(address owner, address spender) view returns (uint256)',
   'function balanceOf(address account) view returns (uint256)',
+  'function decimals() view returns (uint8)',
 ]);
 
 async function main() {
@@ -83,10 +103,15 @@ Usage:
   pnpm tsx scripts/permit2-approval.ts approve [tokenAddress]
   pnpm tsx scripts/permit2-approval.ts revoke  [tokenAddress]
 
-If tokenAddress is not provided, processes all known tokens (USDC and MockERC20).
+If tokenAddress is not provided, processes the chain's primary Permit2 asset
+(EVM_PERMIT2_ASSET). Pass an explicit address to operate on a different token.
 
 Environment variables required:
   CLIENT_EVM_PRIVATE_KEY - Private key of the client wallet
+  EVM_NETWORK            - CAIP-2 EVM chain id (e.g. eip155:84532)
+  EVM_PERMIT2_ASSET      - Permit2 target token address for EVM_NETWORK
+                           (optional when [tokenAddress] is provided)
+  EVM_RPC_URL            - Optional RPC override; falls back to viem chain default
 `);
     process.exit(1);
   }
@@ -97,6 +122,13 @@ Environment variables required:
     process.exit(1);
   }
 
+  if (!filterAddress && Object.keys(TOKENS).length === 0) {
+    console.error(
+      '❌ EVM_PERMIT2_ASSET environment variable is required when no tokenAddress is provided',
+    );
+    process.exit(1);
+  }
+
   const account = privateKeyToAccount(privateKey as `0x${string}`);
 
   const publicClient = createPublicClient({
@@ -110,6 +142,23 @@ Environment variables required:
     transport: http(evmRpcUrl),
   });
 
+  // For a CLI-override token not already in TOKENS, read its decimals on-chain.
+  if (
+    filterAddress &&
+    !Object.values(TOKENS).some((t) => getAddress(t.address) === filterAddress)
+  ) {
+    const decimals = await publicClient.readContract({
+      address: filterAddress,
+      abi: erc20Abi,
+      functionName: 'decimals',
+    });
+    TOKENS[filterAddress] = {
+      address: filterAddress,
+      decimals: Number(decimals),
+      name: filterAddress,
+    };
+  }
+
   console.log(`\n🔑 Wallet: ${account.address}`);
   console.log(`📍 Network: ${evmChain.name} (${evmNetwork})`);
   console.log(`🔐 Permit2: ${PERMIT2_ADDRESS}\n`);
diff --git a/e2e/servers/express/index.ts b/e2e/servers/express/index.ts
index ad1915b305..e37eaad174 100644
--- a/e2e/servers/express/index.ts
+++ b/e2e/servers/express/index.ts
@@ -35,8 +35,17 @@ const APTOS_NETWORK = (process.env.APTOS_NETWORK || "aptos:2") as `${string}:${s
 const HEDERA_NETWORK = (process.env.HEDERA_NETWORK || "hedera:testnet") as `${string}:${string}`;
 const STELLAR_NETWORK = (process.env.STELLAR_NETWORK || "stellar:testnet") as `${string}:${string}`;
 const EVM_PAYEE_ADDRESS = process.env.EVM_PAYEE_ADDRESS as `0x${string}`;
-const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string;
+const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string | undefined;
 const EVM_PERMIT2_ASSET = process.env.EVM_PERMIT2_ASSET as `0x${string}`;
+
+// Token name/version for permit2 EIP-712 domain. Defaults sourced from canonical
+// USDC issuance per chain; falls back to "USDC" for chains we haven't enumerated.
+const EVM_PERMIT2_ASSET_NAMES: Record<string, string> = {
+  "eip155:84532": "USDC",
+  "eip155:8453": "USD Coin",
+};
+const evmPermit2AssetName = EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC";
+
 const AVM_PAYEE_ADDRESS = process.env.AVM_PAYEE_ADDRESS as string;
 const APTOS_PAYEE_ADDRESS = process.env.APTOS_PAYEE_ADDRESS as string;
 const HEDERA_PAYEE_ADDRESS = process.env.HEDERA_PAYEE_ADDRESS as string | undefined;
@@ -50,11 +59,6 @@ if (!EVM_PAYEE_ADDRESS) {
   process.exit(1);
 }
 
-if (!SVM_PAYEE_ADDRESS) {
-  console.error("❌ SVM_PAYEE_ADDRESS environment variable is required");
-  process.exit(1);
-}
-
 if (!facilitatorUrl) {
   console.error("❌ FACILITATOR_URL environment variable is required");
   process.exit(1);
@@ -94,7 +98,9 @@ server.register(
     ...(receiverAuthorizerSigner ? { receiverAuthorizerSigner } : {}),
   }),
 );
-server.register("solana:*", new ExactSvmScheme());
+if (SVM_PAYEE_ADDRESS) {
+  server.register("solana:*", new ExactSvmScheme());
+}
 if (APTOS_PAYEE_ADDRESS) {
   server.register("aptos:*", new ExactAptosScheme());
 }
@@ -127,6 +133,20 @@ app.get("/exact/avm", (req, res, next) => {
   next();
 });
 
+/**
+ * Pre-middleware guard for optional SVM endpoint
+ * Returns 501 Not Implemented if SVM is not configured
+ */
+app.get("/exact/svm", (req, res, next) => {
+  if (!SVM_PAYEE_ADDRESS) {
+    return res.status(501).json({
+      error: "SVM payments not configured",
+      message: "SVM_PAYEE_ADDRESS environment variable is not set",
+    });
+  }
+  next();
+});
+
 /**
  * Pre-middleware guard for optional Aptos endpoint
  * Returns 501 Not Implemented if Aptos is not configured
@@ -226,7 +246,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: evmPermit2AssetName,
               version: "2",
             },
           },
@@ -286,31 +306,35 @@ app.use(
           }),
         },
       },
-      "GET /exact/svm": {
-        accepts: {
-          payTo: SVM_PAYEE_ADDRESS,
-          scheme: "exact",
-          price: "$0.001",
-          network: SVM_NETWORK,
-        },
-        extensions: {
-          ...declareDiscoveryExtension({
-            output: {
-              example: {
-                message: "Protected endpoint accessed successfully",
-                timestamp: "2024-01-01T00:00:00Z",
-              },
-              schema: {
-                properties: {
-                  message: { type: "string" },
-                  timestamp: { type: "string" },
+      ...(SVM_PAYEE_ADDRESS
+        ? {
+          "GET /exact/svm": {
+            accepts: {
+              payTo: SVM_PAYEE_ADDRESS,
+              scheme: "exact",
+              price: "$0.001",
+              network: SVM_NETWORK,
+            },
+            extensions: {
+              ...declareDiscoveryExtension({
+                output: {
+                  example: {
+                    message: "Protected endpoint accessed successfully",
+                    timestamp: "2024-01-01T00:00:00Z",
+                  },
+                  schema: {
+                    properties: {
+                      message: { type: "string" },
+                      timestamp: { type: "string" },
+                    },
+                    required: ["message", "timestamp"],
+                  },
                 },
-                required: ["message", "timestamp"],
-              },
+              }),
             },
-          }),
-        },
-      },
+          },
+        }
+        : {}),
       ...(APTOS_PAYEE_ADDRESS
         ? {
           "GET /exact/aptos": {
@@ -401,7 +425,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: evmPermit2AssetName,
               version: "2",
             },
           },
@@ -468,7 +492,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: evmPermit2AssetName,
               version: "2",
             },
           },
@@ -486,7 +510,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: evmPermit2AssetName,
               version: "2",
             },
           },
@@ -780,7 +804,7 @@ app.listen(parseInt(PORT), () => {
 ║  Stellar Network: ${STELLAR_NETWORK}║
 ║  AVM Payee:    ${AVM_PAYEE_ADDRESS || "(not configured)"}
 ║  EVM Payee:    ${EVM_PAYEE_ADDRESS}                    ║
-║  SVM Payee:    ${SVM_PAYEE_ADDRESS}                    ║
+║  SVM Payee:    ${SVM_PAYEE_ADDRESS || "(not configured)"}
 ║  Aptos Payee:  ${APTOS_PAYEE_ADDRESS || "(not configured)"}
 ║  Hedera Payee: ${HEDERA_PAYEE_ADDRESS || "(not configured)"}
 ║  Stellar Payee: ${STELLAR_PAYEE_ADDRESS || "(not configured)"}
diff --git a/e2e/servers/fastify/index.ts b/e2e/servers/fastify/index.ts
index 0b9863a9c7..720b373c8b 100644
--- a/e2e/servers/fastify/index.ts
+++ b/e2e/servers/fastify/index.ts
@@ -35,8 +35,17 @@ const HEDERA_NETWORK = (process.env.HEDERA_NETWORK || "hedera:testnet") as `${st
 const AVM_NETWORK = (process.env.AVM_NETWORK || "algorand:SGO1GKSzyE7IEPItTxCByw9x8FmnrCDexi9/cOUJOiI=") as `${string}:${string}`;
 const STELLAR_NETWORK = (process.env.STELLAR_NETWORK || "stellar:testnet") as `${string}:${string}`;
 const EVM_PAYEE_ADDRESS = process.env.EVM_PAYEE_ADDRESS as `0x${string}`;
-const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string;
+const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string | undefined;
 const EVM_PERMIT2_ASSET = process.env.EVM_PERMIT2_ASSET as `0x${string}`;
+
+// Token name/version for permit2 EIP-712 domain. Defaults are sourced from the
+// canonical USDC issuance per chain; falls back to "USDC"/"2" for chains we
+// haven't yet enumerated. Add entries when new chains land in EVM_NETWORK_CONFIGS.
+const EVM_PERMIT2_ASSET_NAMES: Record<string, string> = {
+  "eip155:84532": "USDC",
+  "eip155:8453": "USD Coin",
+};
+const evmPermit2AssetName = EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC";
 const AVM_PAYEE_ADDRESS = process.env.AVM_PAYEE_ADDRESS as string;
 const APTOS_PAYEE_ADDRESS = process.env.APTOS_PAYEE_ADDRESS as string;
 const HEDERA_PAYEE_ADDRESS = process.env.HEDERA_PAYEE_ADDRESS as string | undefined;
@@ -50,11 +59,6 @@ if (!EVM_PAYEE_ADDRESS) {
   process.exit(1);
 }
 
-if (!SVM_PAYEE_ADDRESS) {
-  console.error("❌ SVM_PAYEE_ADDRESS environment variable is required");
-  process.exit(1);
-}
-
 if (!facilitatorUrl) {
   console.error("❌ FACILITATOR_URL environment variable is required");
   process.exit(1);
@@ -90,7 +94,9 @@ server.register(
     ...(receiverAuthorizerSigner ? { receiverAuthorizerSigner } : {}),
   }),
 );
-server.register("solana:*", new ExactSvmScheme());
+if (SVM_PAYEE_ADDRESS) {
+  server.register("solana:*", new ExactSvmScheme());
+}
 if (APTOS_PAYEE_ADDRESS) {
   server.register("aptos:*", new ExactAptosScheme());
 }
@@ -121,6 +127,12 @@ app.addHook("onRequest", async (request, reply) => {
       message: "AVM_PAYEE_ADDRESS environment variable is not set",
     });
   }
+  if (path === "/exact/svm" && !SVM_PAYEE_ADDRESS) {
+    return reply.status(501).send({
+      error: "SVM payments not configured",
+      message: "SVM_PAYEE_ADDRESS environment variable is not set",
+    });
+  }
   if (path === "/exact/aptos" && !APTOS_PAYEE_ADDRESS) {
     return reply.status(501).send({
       error: "Aptos payments not configured",
@@ -198,7 +210,7 @@ paymentMiddleware(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -258,31 +270,35 @@ paymentMiddleware(
         }),
       },
     },
-    "GET /exact/svm": {
-      accepts: {
-        payTo: SVM_PAYEE_ADDRESS,
-        scheme: "exact",
-        price: "$0.001",
-        network: SVM_NETWORK,
-      },
-      extensions: {
-        ...declareDiscoveryExtension({
-          output: {
-            example: {
-              message: "Protected endpoint accessed successfully",
-              timestamp: "2024-01-01T00:00:00Z",
-            },
-            schema: {
-              properties: {
-                message: { type: "string" },
-                timestamp: { type: "string" },
+    ...(SVM_PAYEE_ADDRESS
+      ? {
+        "GET /exact/svm": {
+          accepts: {
+            payTo: SVM_PAYEE_ADDRESS,
+            scheme: "exact",
+            price: "$0.001",
+            network: SVM_NETWORK,
+          },
+          extensions: {
+            ...declareDiscoveryExtension({
+              output: {
+                example: {
+                  message: "Protected endpoint accessed successfully",
+                  timestamp: "2024-01-01T00:00:00Z",
+                },
+                schema: {
+                  properties: {
+                    message: { type: "string" },
+                    timestamp: { type: "string" },
+                  },
+                  required: ["message", "timestamp"],
+                },
               },
-              required: ["message", "timestamp"],
-            },
+            }),
           },
-        }),
-      },
-    },
+        },
+      }
+      : {}),
     ...(HEDERA_PAYEE_ADDRESS
       ? {
           "GET /exact/hedera": {
@@ -355,7 +371,7 @@ paymentMiddleware(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -439,7 +455,7 @@ paymentMiddleware(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -456,7 +472,7 @@ paymentMiddleware(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -751,7 +767,7 @@ app.listen({ port: parseInt(PORT) }, (err, address) => {
 ║  Stellar Network: ${STELLAR_NETWORK}║
 ║  AVM Payee:    ${AVM_PAYEE_ADDRESS || "(not configured)"}
 ║  EVM Payee:    ${EVM_PAYEE_ADDRESS}                    ║
-║  SVM Payee:    ${SVM_PAYEE_ADDRESS}                    ║
+║  SVM Payee:    ${SVM_PAYEE_ADDRESS || "(not configured)"}
 ║  Aptos Payee:  ${APTOS_PAYEE_ADDRESS || "(not configured)"}
 ║  Hedera Payee: ${HEDERA_PAYEE_ADDRESS || "(not configured)"}
 ║  Stellar Payee: ${STELLAR_PAYEE_ADDRESS || "(not configured)"}
diff --git a/e2e/servers/hono/index.ts b/e2e/servers/hono/index.ts
index 8a31c20004..20c9a5f628 100644
--- a/e2e/servers/hono/index.ts
+++ b/e2e/servers/hono/index.ts
@@ -36,7 +36,13 @@ const HEDERA_NETWORK = (process.env.HEDERA_NETWORK || "hedera:testnet") as `${st
 const AVM_NETWORK = (process.env.AVM_NETWORK || "algorand:SGO1GKSzyE7IEPItTxCByw9x8FmnrCDexi9/cOUJOiI=") as `${string}:${string}`;
 const STELLAR_NETWORK = (process.env.STELLAR_NETWORK || "stellar:testnet") as `${string}:${string}`;
 const EVM_PAYEE_ADDRESS = process.env.EVM_PAYEE_ADDRESS as `0x${string}`;
-const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string;
+const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string | undefined;
+// Token name/version for permit2 EIP-712 domain. Defaults sourced from canonical
+// USDC issuance per chain; falls back to "USDC" for chains we haven't enumerated.
+const EVM_PERMIT2_ASSET_NAMES: Record<string, string> = {
+  "eip155:84532": "USDC",
+  "eip155:8453": "USD Coin",
+};
 const APTOS_PAYEE_ADDRESS = process.env.APTOS_PAYEE_ADDRESS as string;
 const HEDERA_PAYEE_ADDRESS = process.env.HEDERA_PAYEE_ADDRESS as string | undefined;
 const AVM_PAYEE_ADDRESS = process.env.AVM_PAYEE_ADDRESS as string;
@@ -51,11 +57,6 @@ if (!EVM_PAYEE_ADDRESS) {
   process.exit(1);
 }
 
-if (!SVM_PAYEE_ADDRESS) {
-  console.error("❌ SVM_PAYEE_ADDRESS environment variable is required");
-  process.exit(1);
-}
-
 if (!facilitatorUrl) {
   console.error("❌ FACILITATOR_URL environment variable is required");
   process.exit(1);
@@ -95,7 +96,9 @@ x402Server.register(
     ...(receiverAuthorizerSigner ? { receiverAuthorizerSigner } : {}),
   }),
 );
-x402Server.register("solana:*", new ExactSvmScheme());
+if (SVM_PAYEE_ADDRESS) {
+  x402Server.register("solana:*", new ExactSvmScheme());
+}
 if (APTOS_PAYEE_ADDRESS) {
   x402Server.register("aptos:*", new ExactAptosScheme());
 }
@@ -131,6 +134,23 @@ app.use("/exact/avm", async (c, next) => {
   await next();
 });
 
+/**
+ * Pre-middleware guard for optional SVM endpoint
+ * Returns 501 Not Implemented if SVM is not configured
+ */
+app.use("/exact/svm", async (c, next) => {
+  if (!SVM_PAYEE_ADDRESS) {
+    return c.json(
+      {
+        error: "SVM payments not configured",
+        message: "SVM_PAYEE_ADDRESS environment variable is not set",
+      },
+      501,
+    );
+  }
+  await next();
+});
+
 /**
  * Pre-middleware guard for optional Aptos endpoint
  * Returns 501 Not Implemented if Aptos is not configured
@@ -237,7 +257,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC",
               version: "2",
             },
           },
@@ -297,31 +317,35 @@ app.use(
           }),
         },
       },
-      "GET /exact/svm": {
-        accepts: {
-          payTo: SVM_PAYEE_ADDRESS,
-          scheme: "exact",
-          price: "$0.001",
-          network: SVM_NETWORK,
-        },
-        extensions: {
-          ...declareDiscoveryExtension({
-            output: {
-              example: {
-                message: "Protected endpoint accessed successfully",
-                timestamp: "2024-01-01T00:00:00Z",
-              },
-              schema: {
-                properties: {
-                  message: { type: "string" },
-                  timestamp: { type: "string" },
+      ...(SVM_PAYEE_ADDRESS
+        ? {
+          "GET /exact/svm": {
+            accepts: {
+              payTo: SVM_PAYEE_ADDRESS,
+              scheme: "exact",
+              price: "$0.001",
+              network: SVM_NETWORK,
+            },
+            extensions: {
+              ...declareDiscoveryExtension({
+                output: {
+                  example: {
+                    message: "Protected endpoint accessed successfully",
+                    timestamp: "2024-01-01T00:00:00Z",
+                  },
+                  schema: {
+                    properties: {
+                      message: { type: "string" },
+                      timestamp: { type: "string" },
+                    },
+                    required: ["message", "timestamp"],
+                  },
                 },
-                required: ["message", "timestamp"],
-              },
+              }),
             },
-          }),
-        },
-      },
+          },
+        }
+        : {}),
       ...(APTOS_PAYEE_ADDRESS
         ? {
           "GET /exact/aptos": {
@@ -393,7 +417,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC",
               version: "2",
             },
           },
@@ -477,7 +501,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC",
               version: "2",
             },
           },
@@ -495,7 +519,7 @@ app.use(
             asset: EVM_PERMIT2_ASSET,
             extra: {
               assetTransferMethod: "permit2",
-              name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+              name: EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC",
               version: "2",
             },
           },
@@ -796,7 +820,7 @@ console.log(`
 ║  Stellar Network: ${STELLAR_NETWORK}                    ║
 ║  AVM Payee:      ${AVM_PAYEE_ADDRESS || "(not configured)"}
 ║  EVM Payee:      ${EVM_PAYEE_ADDRESS}                   ║
-║  SVM Payee:      ${SVM_PAYEE_ADDRESS}                   ║
+║  SVM Payee:      ${SVM_PAYEE_ADDRESS || "(not configured)"}
 ║  Aptos Payee:    ${APTOS_PAYEE_ADDRESS || "(not configured)"}
 ║  Hedera Payee:   ${HEDERA_PAYEE_ADDRESS || "(not configured)"}
 ║  Stellar Payee:  ${STELLAR_PAYEE_ADDRESS || "(not configured)"}
diff --git a/e2e/servers/next/proxy.ts b/e2e/servers/next/proxy.ts
index 0f16f53857..4c8b99a5c0 100644
--- a/e2e/servers/next/proxy.ts
+++ b/e2e/servers/next/proxy.ts
@@ -16,7 +16,7 @@ import {
 } from "@x402/extensions";
 
 export const EVM_PAYEE_ADDRESS = process.env.EVM_PAYEE_ADDRESS as `0x${string}`;
-export const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string;
+export const SVM_PAYEE_ADDRESS = process.env.SVM_PAYEE_ADDRESS as string | undefined;
 export const AVM_PAYEE_ADDRESS = process.env.AVM_PAYEE_ADDRESS as string;
 export const APTOS_PAYEE_ADDRESS = process.env.APTOS_PAYEE_ADDRESS as string;
 export const HEDERA_PAYEE_ADDRESS = process.env.HEDERA_PAYEE_ADDRESS as string | undefined;
@@ -34,6 +34,14 @@ export const STELLAR_NETWORK = (process.env.STELLAR_NETWORK ||
 const EVM_PERMIT2_ASSET = process.env.EVM_PERMIT2_ASSET as `0x${string}`;
 const facilitatorUrl = process.env.FACILITATOR_URL;
 
+// Token name/version for permit2 EIP-712 domain. Defaults sourced from canonical
+// USDC issuance per chain; falls back to "USDC" for chains we haven't enumerated.
+const EVM_PERMIT2_ASSET_NAMES: Record<string, string> = {
+  "eip155:84532": "USDC",
+  "eip155:8453": "USD Coin",
+};
+const evmPermit2AssetName = EVM_PERMIT2_ASSET_NAMES[EVM_NETWORK] ?? "USDC";
+
 if (!facilitatorUrl) {
   console.error("❌ FACILITATOR_URL environment variable is required");
   process.exit(1);
@@ -70,7 +78,9 @@ server.register(
     ...(receiverAuthorizerSigner ? { receiverAuthorizerSigner } : {}),
   }),
 );
-server.register("solana:*", new ExactSvmScheme());
+if (SVM_PAYEE_ADDRESS) {
+  server.register("solana:*", new ExactSvmScheme());
+}
 if (APTOS_PAYEE_ADDRESS) {
   server.register("aptos:*", new ExactAptosScheme());
 }
@@ -106,7 +116,7 @@ export const proxy = paymentProxy(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -166,31 +176,35 @@ export const proxy = paymentProxy(
         }),
       },
     },
-    "/api/exact/svm": {
-      accepts: {
-        payTo: SVM_PAYEE_ADDRESS,
-        scheme: "exact",
-        price: "$0.001",
-        network: SVM_NETWORK,
-      },
-      extensions: {
-        ...declareDiscoveryExtension({
-          output: {
-            example: {
-              message: "Protected endpoint accessed successfully",
-              timestamp: "2024-01-01T00:00:00Z",
-            },
-            schema: {
-              properties: {
-                message: { type: "string" },
-                timestamp: { type: "string" },
+    ...(SVM_PAYEE_ADDRESS
+      ? {
+        "/api/exact/svm": {
+          accepts: {
+            payTo: SVM_PAYEE_ADDRESS,
+            scheme: "exact",
+            price: "$0.001",
+            network: SVM_NETWORK,
+          },
+          extensions: {
+            ...declareDiscoveryExtension({
+              output: {
+                example: {
+                  message: "Protected endpoint accessed successfully",
+                  timestamp: "2024-01-01T00:00:00Z",
+                },
+                schema: {
+                  properties: {
+                    message: { type: "string" },
+                    timestamp: { type: "string" },
+                  },
+                  required: ["message", "timestamp"],
+                },
               },
-              required: ["message", "timestamp"],
-            },
+            }),
           },
-        }),
-      },
-    },
+        },
+      }
+      : {}),
     ...(AVM_PAYEE_ADDRESS
       ? {
         "/api/exact/avm": {
@@ -399,7 +413,7 @@ export const proxy = paymentProxy(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
@@ -415,7 +429,7 @@ export const proxy = paymentProxy(
           asset: EVM_PERMIT2_ASSET,
           extra: {
             assetTransferMethod: "permit2",
-            name: EVM_NETWORK == "eip155:84532" ? "USDC" : "USD Coin",
+            name: evmPermit2AssetName,
             version: "2",
           },
         },
diff --git a/e2e/src/cli/args.ts b/e2e/src/cli/args.ts
index 847f1bfcec..b5155b2aaa 100644
--- a/e2e/src/cli/args.ts
+++ b/e2e/src/cli/args.ts
@@ -14,6 +14,7 @@ export interface ParsedArgs {
   showHelp: boolean;
   minimize: boolean;
   networkMode?: NetworkMode;  // undefined = prompt user, set = skip prompt
+  evmNetwork?: string;  // CAIP-2 EVM override (e.g. eip155:31611), overlays mode default
   parallel: boolean;
   concurrency: number;
   endpoints?: string[];
@@ -87,6 +88,9 @@ export function parseArgs(): ParsedArgs {
     networkMode = 'testnet';
   }
 
+  // Parse EVM network override (CAIP-2, e.g. eip155:31611 for Mezo Testnet)
+  const evmNetwork = args.find(arg => arg.startsWith('--evm-network='))?.split('=')[1];
+
   // Parse filters (comma-separated lists)
   const transports = parseListArg(args, '--transport');
   const facilitators = parseListArg(args, '--facilitators');
@@ -117,6 +121,7 @@ export function parseArgs(): ParsedArgs {
     showHelp: false,
     minimize,
     networkMode,
+    evmNetwork,
     parallel,
     concurrency,
     endpoints,
@@ -140,6 +145,7 @@ export function printHelp(): void {
   console.log('Network Selection:');
   console.log('  --testnet                  Use testnet networks');
   console.log('  --mainnet                  Use mainnet networks ⚠️  Real funds!');
+  console.log('  --evm-network=<caip2>      Override EVM slot (e.g. eip155:31611 for Mezo Testnet)');
   console.log('  (If not specified, will prompt in interactive mode)');
   console.log('');
   console.log('Programmatic Mode (for CI/workflows):');
diff --git a/e2e/src/networks/networks.ts b/e2e/src/networks/networks.ts
index 472151990d..92d63679fa 100644
--- a/e2e/src/networks/networks.ts
+++ b/e2e/src/networks/networks.ts
@@ -1,10 +1,15 @@
 /**
  * Network configuration for E2E tests
- * 
+ *
  * This is the single source of truth for all network configs.
- * Use getNetworkSet() to get configs for testnet or mainnet mode.
+ * Use getNetworkSet() to get configs for testnet or mainnet mode (Base-only shortcut).
+ * Use getEvmNetworkConfig() for any EVM chain in DEFAULT_STABLECOINS by CAIP-2 id.
  */
 
+import { DEFAULT_STABLECOINS } from '@x402/evm';
+import { type Chain, defineChain } from 'viem';
+import * as allChains from 'viem/chains';
+
 export type NetworkMode = 'testnet' | 'mainnet';
 export type ProtocolFamily = 'evm' | 'svm' | 'avm' | 'aptos' | 'hedera' | 'stellar' | 'tvm';
 
@@ -25,6 +30,20 @@ export type NetworkSet = {
   tvm: NetworkConfig;
 };
 
+/**
+ * Resolve the EVM RPC URL for a chain. Single-knob configuration:
+ *   1. `EVM_RPC_URL` override (matches the harness-wide convention used by
+ *      e2e/test.ts, e2e/facilitators/*, and e2e/clients/*).
+ *   2. viem's chain default (covers public chains shipped by viem).
+ *   3. Empty string when neither applies — preserves the prior
+ *      `process.env.X || ''` semantics so module load never throws.
+ */
+function evmRpcUrl(caip2: string): string {
+  const override = process.env.EVM_RPC_URL?.trim();
+  if (override) return override;
+  return resolveViemChain(caip2).rpcUrls.default?.http?.[0] ?? '';
+}
+
 /**
  * All supported networks, organized by mode and protocol family
  */
@@ -33,7 +52,7 @@ const NETWORK_SETS: Record<NetworkMode, NetworkSet> = {
     evm: {
       name: 'Base Sepolia',
       caip2: 'eip155:84532',
-      rpcUrl: process.env.BASE_SEPOLIA_RPC_URL || 'https://sepolia.base.org',
+      rpcUrl: evmRpcUrl('eip155:84532'),
       permit2Asset: '0x036CbD53842c5426634e7929541eC2318f3dCF7e',
     },
     svm: {
@@ -71,7 +90,7 @@ const NETWORK_SETS: Record<NetworkMode, NetworkSet> = {
     evm: {
       name: 'Base',
       caip2: 'eip155:8453',
-      rpcUrl: process.env.BASE_RPC_URL || 'https://mainnet.base.org',
+      rpcUrl: evmRpcUrl('eip155:8453'),
       permit2Asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
     },
     svm: {
@@ -108,13 +127,20 @@ const NETWORK_SETS: Record<NetworkMode, NetworkSet> = {
 };
 
 /**
- * Get the network set for a given mode
- * 
+ * Get the network set for a given mode, optionally overriding the EVM slot.
+ *
  * @param mode - 'testnet' or 'mainnet'
+ * @param evmCaip2 - Optional CAIP-2 EVM identifier; when provided the `evm`
+ *   slot is overlaid from {@link EVM_NETWORK_CONFIGS} so the harness can
+ *   target chains beyond the mode's default (e.g. Mezo Testnet on a `--testnet` run).
  * @returns NetworkSet containing configured protocol network configs
  */
-export function getNetworkSet(mode: NetworkMode): NetworkSet {
-  return NETWORK_SETS[mode];
+export function getNetworkSet(mode: NetworkMode, evmCaip2?: string): NetworkSet {
+  const base = NETWORK_SETS[mode];
+  if (!evmCaip2 || evmCaip2 === base.evm.caip2) {
+    return base;
+  }
+  return { ...base, evm: getEvmNetworkConfig(evmCaip2) };
 }
 
 /**
@@ -150,7 +176,7 @@ export function getNetworkForProtocol(
 
 /**
  * Get display string for a network mode
- * 
+ *
  * @param mode - 'testnet' or 'mainnet'
  * @returns Human-readable description of the networks
  */
@@ -159,3 +185,76 @@ export function getNetworkModeDescription(mode: NetworkMode): string {
   const networks = [set.evm.name, set.svm.name, set.avm.name, set.aptos.name, set.hedera.name, set.stellar.name, set.tvm.name];
   return networks.join(' + ');
 }
+
+/**
+ * Per-chain EVM network configurations indexed by CAIP-2 identifier.
+ * Derived at module load from {@link DEFAULT_STABLECOINS} (the SDK's
+ * canonical chain catalog) so adding a chain there propagates here
+ * automatically — no parallel hand-curated table to keep in sync.
+ *
+ * Display name comes from viem's chain database, falling back to
+ * `EVM ${chainId}` for chains viem hasn't shipped.
+ *
+ * RPC URLs resolve via {@link evmRpcUrl}: `EVM_RPC_URL` overrides everything,
+ * otherwise viem's chain default is used (empty string when viem ships no
+ * default).
+ * `permit2Asset` is the chain's default stablecoin (also the Permit2 target for
+ * tests that exercise the permit2 / EIP-2612 path).
+ */
+export const EVM_NETWORK_CONFIGS: Record<string, NetworkConfig> = Object.fromEntries(
+  Object.keys(DEFAULT_STABLECOINS).map(caip2 => [
+    caip2,
+    {
+      name: resolveViemChain(caip2).name,
+      caip2: caip2 as `${string}:${string}`,
+      rpcUrl: evmRpcUrl(caip2),
+      permit2Asset: DEFAULT_STABLECOINS[caip2].address,
+    },
+  ]),
+);
+
+/**
+ * Get NetworkConfig for an EVM chain by CAIP-2 identifier.
+ *
+ * @param caip2 - CAIP-2 EVM identifier (e.g. "eip155:84532")
+ * @returns NetworkConfig for the chain
+ * @throws If the network is not in the configured list
+ */
+export function getEvmNetworkConfig(caip2: string): NetworkConfig {
+  const config = EVM_NETWORK_CONFIGS[caip2];
+  if (!config) {
+    throw new Error(
+      `No EVM network config for ${caip2}. Supported: ${Object.keys(EVM_NETWORK_CONFIGS).join(', ')}`,
+    );
+  }
+  return config;
+}
+
+/**
+ * Map a CAIP-2 EVM identifier to a viem `Chain`.
+ *
+ * Looks up viem's chain database; falls back to a minimal `defineChain` so
+ * that EVM networks viem hasn't yet packaged still work for callers supplying
+ * their own `EVM_RPC_URL`.
+ *
+ * @param caip2 - CAIP-2 EVM identifier (e.g. "eip155:84532")
+ * @returns viem Chain object suitable for createPublicClient/createWalletClient
+ */
+export function resolveViemChain(caip2: string): Chain {
+  const [namespace, ref] = caip2.split(':');
+  if (namespace !== 'eip155') {
+    throw new Error(`resolveViemChain: not an EVM network: ${caip2}`);
+  }
+  const chainId = Number(ref);
+  if (!Number.isInteger(chainId) || chainId <= 0) {
+    throw new Error(`resolveViemChain: invalid EVM chain id in ${caip2}`);
+  }
+  const known = (Object.values(allChains) as Chain[]).find(c => c.id === chainId);
+  if (known) return known;
+  return defineChain({
+    id: chainId,
+    name: `EVM ${chainId}`,
+    nativeCurrency: { name: 'Ether', symbol: 'ETH', decimals: 18 },
+    rpcUrls: { default: { http: [] } },
+  });
+}
diff --git a/e2e/src/servers/generic-server.ts b/e2e/src/servers/generic-server.ts
index 3d1d63ca0b..afc672f9b5 100644
--- a/e2e/src/servers/generic-server.ts
+++ b/e2e/src/servers/generic-server.ts
@@ -258,10 +258,20 @@ export class GenericServerProxy extends BaseProxy implements ServerProxy {
 }
 
 /**
- * Translates v2 CAIP-2 network format to v1 simple format for legacy servers
- * 
+ * Translates v2 CAIP-2 network format to v1 simple format for legacy servers.
+ *
+ * Activated only when {@link this.directory} contains `legacy/` (see
+ * `isV1Server` gate in this file). For v2 (non-legacy) servers this function
+ * is dead code: callers pass the v2 CAIP-2 string straight through unchanged.
+ *
+ * The hardcoded map covers the v1 chains the legacy harness was built around
+ * (Base / Base Sepolia, Solana mainnet / devnet); any other CAIP-2 input
+ * falls through unchanged. When `e2e/legacy/*` is retired this entire
+ * translator can be deleted.
+ *
  * @param network - Network in CAIP-2 format (e.g., "eip155:84532")
- * @returns Network in v1 format (e.g., "base-sepolia")
+ * @returns Network in v1 format (e.g., "base-sepolia") for known mappings,
+ *   otherwise the input is returned unchanged.
  */
 function translateNetworkForV1(network: string): string {
   const networkMap: Record<string, string> = {
diff --git a/e2e/test.ts b/e2e/test.ts
index f278753bfd..4e0ee541a3 100644
--- a/e2e/test.ts
+++ b/e2e/test.ts
@@ -4,7 +4,6 @@ import { writeFileSync } from 'fs';
 import { join } from 'path';
 import { createWalletClient, createPublicClient, http, parseEther, formatEther, toHex } from 'viem';
 import { privateKeyToAccount } from 'viem/accounts';
-import { base, baseSepolia } from 'viem/chains';
 import { TestDiscovery } from './src/discovery';
 import { ClientConfig, ScenarioResult, ServerConfig, TestScenario, endpointAssetTransferMethod, endpointPaymentScheme, endpointUsesBatchSettlement } from './src/types';
 import { config as loggerConfig, log, verboseLog, errorLog, close as closeLogger, createComboLogger } from './src/logger';
@@ -13,7 +12,7 @@ import { parseArgs, printHelp } from './src/cli/args';
 import { runInteractiveMode } from './src/cli/interactive';
 import { filterScenarios, TestFilters, shouldShowExtensionOutput } from './src/cli/filters';
 import { minimizeScenarios } from './src/sampling';
-import { getNetworkSet, NetworkMode, getNetworkModeDescription, resolveEvmPermit2Asset } from './src/networks/networks';
+import { getNetworkSet, NetworkMode, getNetworkModeDescription, resolveEvmPermit2Asset, resolveViemChain } from './src/networks/networks';
 import { GenericServerProxy } from './src/servers/generic-server';
 import { Semaphore, FacilitatorLock } from './src/concurrency';
 import { FacilitatorManager } from './src/facilitators/facilitator-manager';
@@ -139,7 +138,7 @@ async function revokePermit2Approval(tokenAddress?: string): Promise<boolean> {
 function getEvmClients() {
   const evmNetwork = process.env.EVM_NETWORK || 'eip155:84532';
   const evmRpcUrl = process.env.EVM_RPC_URL;
-  const evmChain = evmNetwork === 'eip155:8453' ? base : baseSepolia;
+  const evmChain = resolveViemChain(evmNetwork);
 
   const facilitatorKey = process.env.FACILITATOR_EVM_PRIVATE_KEY;
   const clientKey = process.env.CLIENT_EVM_PRIVATE_KEY;
@@ -511,11 +510,6 @@ async function runTest() {
   const facilitatorStellarPrivateKey = process.env.FACILITATOR_STELLAR_PRIVATE_KEY;
   const facilitatorTvmPrivateKey = process.env.FACILITATOR_TVM_PRIVATE_KEY;
   const batchSettlementRecovery = envFlagDefaultTrue(process.env.BATCH_SETTLEMENT_RECOVERY);
-  if (!serverEvmAddress || !serverSvmAddress || !clientEvmPrivateKey || !clientSvmPrivateKey || !facilitatorEvmPrivateKey || !facilitatorSvmPrivateKey) {
-    errorLog('❌ Missing required environment variables:');
-    errorLog(' SERVER_EVM_ADDRESS, SERVER_SVM_ADDRESS, CLIENT_EVM_PRIVATE_KEY, CLIENT_SVM_PRIVATE_KEY, FACILITATOR_EVM_PRIVATE_KEY, and FACILITATOR_SVM_PRIVATE_KEY must be set');
-    process.exit(1);
-  }
 
   // Discover all servers, clients, and facilitators (always include legacy)
   const discovery = new TestDiscovery('.', true); // Always discover legacy
@@ -580,8 +574,8 @@ async function runTest() {
     }
   }
 
-  // Get network configuration based on selected mode
-  const networks = getNetworkSet(networkMode);
+  // Get network configuration based on selected mode, with optional CLI EVM override
+  const networks = getNetworkSet(networkMode, parsedArgs.evmNetwork);
   const evmPermit2Asset = resolveEvmPermit2Asset(networks);
 
   const permit2AssetSource = process.env.EVM_PERMIT2_ASSET?.trim()