refactor(vibenet): simplify conditional withdrawal contract

app/vibenet/demos/catalogue.test.ts

@@ -44,10 +44,11 @@ describe('DEMOS', () => {
     expect(new Set(hrefs).size).toBe(hrefs.length);
   });
 
-  it('lists Validity Transactions as a top-level group', () => {
-    const validity = listedDemos().find((demo) => demo.href === '/vibenet/demos/validity');
+  it('keeps Validity Transactions reachable but hidden from the top-level grid', () => {
+    const validity = DEMOS.find((demo) => demo.href === '/vibenet/demos/validity');
     expect(validity?.title).toBe('Validity Transactions');
     expect(validity?.children?.map((demo) => demo.title)).toEqual(['Conditional Swaps', 'Race the Agent']);
+    expect(listedDemos()).not.toContain(validity);
   });
 });
 

app/vibenet/demos/catalogue.ts

@@ -67,6 +67,7 @@ export const DEMOS: DemoEntry[] = [
       'Build intent-like flows from ordinary account transactions',
     ],
     available: true,
+    listed: false,
     children: [
       {
         href: '/vibenet/demos/validity/conditional-swaps',

app/vibenet/demos/validity/lib/artifacts/ConditionalWithdrawal.json

@@ -12,13 +12,11 @@
   "source": "../contracts/ConditionalWithdrawal.sol",
   "abi": [
     {"inputs":[{"internalType":"contract IERC20","name":"vibe","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},
-    {"inputs":[],"name":"ENABLED_SLOT","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"view","type":"function"},
     {"inputs":[],"name":"VIBE","outputs":[{"internalType":"contract IERC20","name":"","type":"address"}],"stateMutability":"view","type":"function"},
     {"inputs":[],"name":"WITHDRAWAL_AMOUNT","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},
-    {"inputs":[],"name":"enabled","outputs":[{"internalType":"bool","name":"value","type":"bool"}],"stateMutability":"view","type":"function"},
-    {"inputs":[],"name":"flip","outputs":[{"internalType":"bool","name":"value","type":"bool"}],"stateMutability":"nonpayable","type":"function"},
+    {"inputs":[],"name":"enabled","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},
     {"inputs":[{"internalType":"bool","name":"value","type":"bool"}],"name":"setEnabled","outputs":[],"stateMutability":"nonpayable","type":"function"},
     {"inputs":[],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}
   ],
-  "bytecode": "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"
+  "bytecode": "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"
 }

app/vibenet/demos/validity/lib/conditionalWithdrawal.test.ts

@@ -1,4 +1,4 @@
-import { decodeFunctionData, keccak256, toBytes } from 'viem';
+import { decodeFunctionData } from 'viem';
 import { describe, expect, it } from 'vitest';
 
 import artifact from './artifacts/ConditionalWithdrawal.json';
@@ -14,7 +14,6 @@ import {
   conditionalWithdrawalFundingAmount,
   encodeConditionalWithdrawalFunding,
   encodeConditionalWithdraw,
-  encodeFlipConditionalWithdrawal,
   encodeSetConditionalWithdrawalEnabled,
   predictConditionalWithdrawal,
 } from './conditionalWithdrawal';
@@ -39,39 +38,41 @@ describe('conditional withdrawal contract', () => {
     expect(CONDITIONAL_WITHDRAWAL_SALT).toBe(
       '0x75dea569b8cc7d9ea45d7d95a5d6bed33e1e378a31715724342462f8226adc8b',
     );
-    expect(predictConditionalWithdrawal(VIBE)).toBe('0x7AE1BFB6116D154a0a27961a5d19C544D02015a9');
+    expect(predictConditionalWithdrawal(VIBE)).toBe('0xC655E339224d57B087A02Df7827A4068ae69aba1');
     expect(predictConditionalWithdrawal(OTHER_VIBE)).not.toBe(predictConditionalWithdrawal(VIBE));
   });
 
-  it('pins the stable storage word and exact enabled=true EIP-8130 predicate', () => {
-    expect(CONDITIONAL_WITHDRAWAL_ENABLED_SLOT).toBe(
-      keccak256(toBytes('vibenet.validity.conditional-withdrawal.enabled.v1')),
-    );
-    expect(CONDITIONAL_WITHDRAWAL_ENABLED_MASK).toBe((1n << 256n) - 1n);
+  it('reads bool public enabled from slot 0 in the EIP-8130 predicate', () => {
+    expect(CONDITIONAL_WITHDRAWAL_ENABLED_SLOT).toBe(0n);
+    expect(CONDITIONAL_WITHDRAWAL_ENABLED_MASK).toBe(0xffn);
     expect(conditionalWithdrawalEnabledPredicate(WITHDRAWAL)).toEqual({
       type: 'storage',
       params: {
         address: WITHDRAWAL,
-        slot: CONDITIONAL_WITHDRAWAL_ENABLED_SLOT,
-        mask: toWord((1n << 256n) - 1n),
+        slot: toWord(0n),
+        mask: toWord(0xffn),
         op: '=',
         value: toWord(1n),
       },
     });
   });
 
   it('encodes condition and fixed-withdrawal calls exactly', () => {
+    const functionNames = artifact.abi
+      .filter((item) => item.type === 'function')
+      .map((item) => item.name);
+    expect(functionNames).not.toContain('ENABLED_SLOT');
+    expect(functionNames).not.toContain('flip');
+    expect(functionNames).toContain('enabled');
+    expect(functionNames).toContain('setEnabled');
+    expect(functionNames).toContain('withdraw');
     expect(encodeSetConditionalWithdrawalEnabled(WITHDRAWAL, true)).toEqual({
       to: WITHDRAWAL,
       data: `0x328d8f72${'0'.repeat(63)}1`,
     });
     expect(encodeSetConditionalWithdrawalEnabled(WITHDRAWAL, false).data).toBe(
       `0x328d8f72${'0'.repeat(64)}`,
     );
-    expect(encodeFlipConditionalWithdrawal(WITHDRAWAL)).toEqual({
-      to: WITHDRAWAL,
-      data: '0xcde4efa9',
-    });
     expect(encodeConditionalWithdraw(WITHDRAWAL)).toEqual({
       to: WITHDRAWAL,
       data: '0x3ccfd60b',

app/vibenet/demos/validity/lib/conditionalWithdrawal.ts

@@ -24,9 +24,9 @@ import type { StoragePredicate } from './types';
 export const conditionalWithdrawalAbi = artifact.abi as Abi;
 export const conditionalWithdrawalBytecode = artifact.bytecode as Hex;
 
-export const CONDITIONAL_WITHDRAWAL_ENABLED_SLOT =
-  '0xa91a9aee734204743335c443df931dcb220441d8aa6c1355dc61503a4bec3129' as Hex;
-export const CONDITIONAL_WITHDRAWAL_ENABLED_MASK = (1n << 256n) - 1n;
+/** `bool public enabled` is the contract's first storage variable. */
+export const CONDITIONAL_WITHDRAWAL_ENABLED_SLOT = 0n;
+export const CONDITIONAL_WITHDRAWAL_ENABLED_MASK = 0xffn;
 export const CONDITIONAL_WITHDRAWAL_AMOUNT = WAD;
 export const CONDITIONAL_WITHDRAWAL_REFILL_THRESHOLD = 1_000_000n * WAD;
 export const CONDITIONAL_WITHDRAWAL_FUNDING_TARGET = 2_000_000n * WAD;
@@ -171,25 +171,18 @@ export function encodeSetConditionalWithdrawalEnabled(
   };
 }
 
-export function encodeFlipConditionalWithdrawal(withdrawal: Address): { to: Address; data: Hex } {
-  return {
-    to: withdrawal,
-    data: encodeFunctionData({ abi: conditionalWithdrawalAbi, functionName: 'flip' }),
-  };
-}
-
 export function encodeConditionalWithdraw(withdrawal: Address): { to: Address; data: Hex } {
   return {
     to: withdrawal,
     data: encodeFunctionData({ abi: conditionalWithdrawalAbi, functionName: 'withdraw' }),
   };
 }
 
-/** EIP-8130 condition requiring the stable enabled bit to equal true. */
+/** EIP-8130 condition requiring `bool public enabled` in storage slot 0 to be true. */
 export function conditionalWithdrawalEnabledPredicate(withdrawal: Address): StoragePredicate {
   return storagePredicate(
     withdrawal,
-    BigInt(CONDITIONAL_WITHDRAWAL_ENABLED_SLOT),
+    CONDITIONAL_WITHDRAWAL_ENABLED_SLOT,
     CONDITIONAL_WITHDRAWAL_ENABLED_MASK,
     '=',
     1n,

app/vibenet/demos/validity/lib/contracts/ConditionalWithdrawal.sol

@@ -5,43 +5,23 @@ interface IERC20 {
     function transfer(address to, uint256 amount) external returns (bool);
 }
 
-/// @notice Permissionless condition switch backed by one stable storage word.
+/// @notice Permissionless VIBE withdrawal controlled by a boolean condition.
 contract ConditionalWithdrawal {
-    /// @dev Stable forever: keccak256("vibenet.validity.conditional-withdrawal.enabled.v1").
-    bytes32 public constant ENABLED_SLOT =
-        0xa91a9aee734204743335c443df931dcb220441d8aa6c1355dc61503a4bec3129;
     uint256 public constant WITHDRAWAL_AMOUNT = 1 ether;
 
     IERC20 public immutable VIBE;
+    bool public enabled;
 
     constructor(IERC20 vibe) {
         VIBE = vibe;
     }
 
-    function enabled() public view returns (bool value) {
-        bytes32 slot = ENABLED_SLOT;
-        assembly {
-            value := iszero(iszero(sload(slot)))
-        }
-    }
-
     function setEnabled(bool value) external {
-        bytes32 slot = ENABLED_SLOT;
-        assembly {
-            sstore(slot, value)
-        }
-    }
-
-    function flip() external returns (bool value) {
-        bytes32 slot = ENABLED_SLOT;
-        assembly {
-            value := iszero(sload(slot))
-            sstore(slot, value)
-        }
+        enabled = value;
     }
 
     function withdraw() external {
-        require(enabled(), "withdrawal disabled");
+        require(enabled, "withdrawal disabled");
         require(VIBE.transfer(msg.sender, WITHDRAWAL_AMOUNT), "transfer failed");
     }
 }

app/vibenet/demos/validity/race-the-agent/RaceTheAgentDemo.tsx

@@ -20,6 +20,7 @@ import { VIBENET_EXPLORER_PATH, VIBENET_WS_URL } from '../../../library/config';
 import { CopyableValue } from '../../../components/CopyableValue';
 import { AccountDemoShell } from '../../_components/AccountDemoShell';
 import { DemoHeader } from '../../_components/DemoHeader';
+import { ChevronIcon } from '../../_shared/dropdown';
 import { newCallRow } from '../../account/library/calls';
 import type { StoredAccount } from '../../account/library/model';
 import { aaReceiptSucceeded, type AaReceiptLike } from '../../account/library/receipt';
@@ -76,6 +77,28 @@ type Observation = { enabled: boolean; block: bigint; at: number };
 type AgentPhase = 'Waiting' | 'Scheduling' | 'Opening' | 'Closing' | 'Retrying';
 
 const EMPTY_ATTEMPT: Attempt = { status: 'idle' };
+const CONTRACT_SNIPPET = `interface IERC20 {
+    function transfer(address to, uint256 amount) external returns (bool);
+}
+
+contract ConditionalWithdrawal {
+    uint256 public constant WITHDRAWAL_AMOUNT = 1 ether;
+    IERC20 public immutable VIBE;
+    bool public enabled;
+
+    constructor(IERC20 vibe) {
+        VIBE = vibe;
+    }
+
+    function setEnabled(bool value) external {
+        enabled = value;
+    }
+
+    function withdraw() external {
+        require(enabled, "withdrawal disabled");
+        require(VIBE.transfer(msg.sender, WITHDRAWAL_AMOUNT), "transfer failed");
+    }
+}`;
 
 function rootAccount(account: StoredAccount, accounts: StoredAccount[]): StoredAccount {
   let current = account;
@@ -778,6 +801,9 @@ function RaceTheAgentDemoInner() {
   });
   const validityAttempts = attemptHistoryRows(validity, validityHistory);
   const manualAttempts = attemptHistoryRows(manual, manualHistory);
+  const predicateSnippet = withdrawal
+    ? JSON.stringify(conditionalWithdrawalEnabledPredicate(withdrawal), null, 2)
+    : 'Resolving the conditional withdrawal address…';
 
   return (
     <AccountDemoShell
@@ -940,6 +966,26 @@ function RaceTheAgentDemoInner() {
         </div>
       </section>
 
+      <details className="group rounded-2xl border border-bds-gray-10 bg-background dark:border-white/10 dark:bg-white/[.04]">
+        <summary className="flex cursor-pointer list-none items-center justify-between gap-4 px-5 py-4 marker:content-none sm:px-6 [&::-webkit-details-marker]:hidden">
+          <div>
+            <Text variant="caption" tone="muted">Advanced details</Text>
+            <Text variant="headline" className="mt-1">Contract and validity predicate</Text>
+          </div>
+          <ChevronIcon className="shrink-0 duration-150 group-open:rotate-180" />
+        </summary>
+        <div className="border-t border-bds-gray-10 px-5 py-5 sm:px-6 dark:border-white/10">
+          <Text variant="label.regular" tone="muted" className="max-w-2xl">
+            Solidity stores the first state variable, <code className="font-mono text-foreground">enabled</code>,
+            in slot 0. The validity transaction reads that slot directly and becomes eligible only when the boolean is true.
+          </Text>
+          <div className="mt-5 grid min-w-0 gap-4 lg:grid-cols-2">
+            <CodeSnippet label="ConditionalWithdrawal.sol" code={CONTRACT_SNIPPET} language="solidity" />
+            <CodeSnippet label="Withdrawal validity predicate" code={predicateSnippet} language="json" />
+          </div>
+        </div>
+      </details>
+
       <section className="grid min-w-0 gap-4 lg:grid-cols-[minmax(0,1.1fr)_minmax(320px,.9fr)]">
         <Card className="min-w-0 overflow-hidden bg-background p-5 sm:p-6 dark:bg-white/[.04]">
           <Text variant="caption" tone="muted">Observed chain state</Text>
@@ -1102,6 +1148,62 @@ function AttemptHistoryCard({ title, attempts }: { title: string; attempts: Atte
   );
 }
 
+type CodeLanguage = 'json' | 'solidity';
+type CodeToken = { text: string; kind: 'comment' | 'key' | 'keyword' | 'literal' | 'number' | 'plain' | 'string' | 'type' };
+
+const CODE_TOKEN_CLASS: Record<CodeToken['kind'], string> = {
+  comment: 'text-bds-gray-50 dark:text-[#7f8c98]',
+  key: 'text-base-blue dark:text-[#7eb8ff]',
+  keyword: 'text-purple-700 dark:text-[#c792ea]',
+  literal: 'text-bds-orange-70 dark:text-[#ff9d76]',
+  number: 'text-bds-orange-70 dark:text-[#f5c542]',
+  plain: 'text-bds-gray-80 dark:text-[#d6deeb]',
+  string: 'text-bds-green-70 dark:text-[#7ee0a8]',
+  type: 'text-base-blue dark:text-[#82aaff]',
+};
+
+function tokenizeCode(source: string, language: CodeLanguage): CodeToken[] {
+  const pattern = language === 'json'
+    ? /("(?:\\u[a-zA-Z0-9]{4}|\\[^u]|[^\\"])*"(?:\s*:)?|\b(?:true|false|null)\b|-?\d+(?:\.\d*)?|[{}[\]:,])/g
+    : /(\/\/[^\n]*|"(?:\\.|[^"\\])*"|\b(?:contract|interface|function|external|public|immutable|constant|returns|return|require|bool|uint256|address)\b|\b(?:IERC20|ConditionalWithdrawal)\b|\b\d+(?:\s+ether)?\b)/g;
+  const tokens: CodeToken[] = [];
+  let last = 0;
+  for (const hit of source.matchAll(pattern)) {
+    const text = hit[0];
+    const index = hit.index ?? 0;
+    if (index > last) tokens.push({ text: source.slice(last, index), kind: 'plain' });
+    let kind: CodeToken['kind'] = 'plain';
+    if (language === 'json') {
+      if (text.startsWith('"')) kind = text.endsWith(':') ? 'key' : 'string';
+      else if (text === 'true' || text === 'false' || text === 'null') kind = 'literal';
+      else if (/^-?\d/.test(text)) kind = 'number';
+    } else if (text.startsWith('//')) kind = 'comment';
+    else if (text.startsWith('"')) kind = 'string';
+    else if (/^\d/.test(text)) kind = 'number';
+    else if (text === 'IERC20' || text === 'ConditionalWithdrawal') kind = 'type';
+    else kind = 'keyword';
+    tokens.push({ text, kind });
+    last = index + text.length;
+  }
+  if (last < source.length) tokens.push({ text: source.slice(last), kind: 'plain' });
+  return tokens;
+}
+
+function CodeSnippet({ label, code, language }: { label: string; code: string; language: CodeLanguage }) {
+  return (
+    <Card className="min-w-0 overflow-hidden bg-background p-4 dark:bg-white/[.04]">
+      <Text variant="caption" tone="muted">{label}</Text>
+      <pre className="mt-3 min-h-80 overflow-auto rounded-xl bg-bds-gray-5 p-4 font-mono text-[11px] leading-5 dark:bg-[#0b0d12]">
+        <code>
+          {tokenizeCode(code, language).map((token, index) => (
+            <span key={`${index}-${token.text}`} className={CODE_TOKEN_CLASS[token.kind]}>{token.text}</span>
+          ))}
+        </code>
+      </pre>
+    </Card>
+  );
+}
+
 function Metric({ label, value }: { label: string; value: string }) {
   return (
     <div className="min-w-0">