[SDK] Make maxAmount optional in wrapFetchWithPayment (#8369)

Author: joaquim-verges

.changeset/famous-owls-lick.md

@@ -0,0 +1,5 @@
+---
+"thirdweb": patch
+---
+
+Make maxAmount optional in wrapFetchWithPayment and loosen schema validation for payment payloads

packages/thirdweb/src/x402/encode.ts

@@ -1,8 +1,5 @@
 import type { ExactEvmPayload } from "x402/types";
-import {
-  type RequestedPaymentPayload,
-  RequestedPaymentPayloadSchema,
-} from "./schemas.js";
+import type { RequestedPaymentPayload } from "./schemas.js";
 
 /**
  * Encodes a payment payload into a base64 string, ensuring bigint values are properly stringified
@@ -44,8 +41,7 @@ export function decodePayment(payment: string): RequestedPaymentPayload {
     ...parsed,
     payload: parsed.payload as ExactEvmPayload,
   };
-  const validated = RequestedPaymentPayloadSchema.parse(obj);
-  return validated;
+  return obj;
 }
 
 /**

packages/thirdweb/src/x402/fetchWithPayment.ts

@@ -52,7 +52,7 @@ export function wrapFetchWithPayment(
   fetch: typeof globalThis.fetch,
   client: ThirdwebClient,
   wallet: Wallet,
-  maxValue: bigint = BigInt(1 * 10 ** 6), // Default to 1 USDC
+  maxValue?: bigint,
 ) {
   return async (input: RequestInfo, init?: RequestInit) => {
     const response = await fetch(input, init);
@@ -91,7 +91,10 @@ export function wrapFetchWithPayment(
       );
     }
 
-    if (BigInt(selectedPaymentRequirements.maxAmountRequired) > maxValue) {
+    if (
+      maxValue &&
+      BigInt(selectedPaymentRequirements.maxAmountRequired) > maxValue
+    ) {
       throw new Error(
         `Payment amount exceeds maximum allowed (currently set to ${maxValue} in base units)`,
       );

packages/thirdweb/src/x402/schemas.ts

@@ -15,7 +15,7 @@ const FacilitatorNetworkSchema = z.string();
 
 export type FacilitatorNetwork = z.infer<typeof FacilitatorNetworkSchema>;
 
-export const RequestedPaymentPayloadSchema = PaymentPayloadSchema.extend({
+const RequestedPaymentPayloadSchema = PaymentPayloadSchema.extend({
   network: FacilitatorNetworkSchema,
 });