> ## Documentation Index > Fetch the complete documentation index at: https://docs.anyspend.com/llms.txt > Use this file to discover all available pages before exploring further. # x402 Crypto Ads Advertise on crypto sites with zero gas fees using x402 [Check out the x402 Ad Marketplace (UI)](https://explorer.b3.fun/apps/x402-ad-marketplace) Buy advertising space on 100+ crypto content sites using USDC with **zero gas fees** thanks to x402 gasless payments. **No Gas Fees** Pay only the ad price - zero transaction fees **Instant Booking** One signature and you're live **100+ Sites** Choose from crypto news, DeFi, NFT sites **AI-Powered Content** Submit articles with AI validation and generation **Real Analytics** See traffic data before you buy **Track Everything** Monitor your ads and article requests in real-time ## Quick Start **Display Ads** **Connect Wallet** Visit [x402 Ad Marketplace](https://explorer.b3.fun/apps/x402-ad-marketplace) and connect your wallet on Base network **Browse Sites** Explore sites with traffic stats, pick your target audience **Choose Format & Time** Select ad format (Banner/Sidebar/Leaderboard) and time slot **Upload Ad** Provide image URL and landing page **Sign & Pay** One signature with USDC - zero gas fees - instant confirmation **Article Submissions** **Connect Wallet** Visit [x402 Ad Marketplace](https://explorer.b3.fun/apps/x402-ad-marketplace) and connect your wallet on Base network **Select Target Site** Choose from crypto news sites that accept article submissions **Submit Your Idea** Provide a tweet URL, topic, or complete article title **AI Validation** Get instant AI feedback with score (0-100) and suggestions **Review & Submit** If approved (score ≥70), submit with one x402 signature **Track Progress** Monitor status and get notified when published Need USDC on Base? Bridge from Ethereum using [Base Bridge](https://bridge.base.org) ## Ad Formats & Pricing **Wide banner** **970×250 pixels** - Wide banner format **Price:** 1 USDC/hour Best for cost-effective campaigns with good visibility **Sidebar** **300×600 pixels** - Vertical side placement **Price:** 2 USDC/hour Best for persistent visibility as users scroll **Leaderboard** **728×90 pixels** - Top banner position **Price:** 3 USDC/hour Best for maximum visibility and brand awareness **Duration:** 1 hour minimum, 7 days (168 hours) maximum ## Article Submissions Submit article ideas to crypto content sites. AI validates your topic and generates optimized titles and descriptions. ### How It Works **Submit Topic or Tweet** Provide a tweet URL, topic idea, or complete article title **AI Validation (Free)** AI scores your content (0-100) and generates suggestions if needed **Get Approval** - **Score ≥80:** Your input is perfect, accepted as-is - **Score 70-79:** Approved with AI-improved suggestions - **Score <70:** Rejected - try a different topic **Submit & Pay** One x402 signature to submit your article request **Publication** Site publishes your article and you receive the live URL ### Pricing Prices vary by site, typically **$3-50 USDC** per article. Each site sets their own rate based on traffic and audience. Validation is free! You can validate as many ideas as you want before committing to payment. ## API Reference ### Network & Payment Details Chain ID: 8453 6 decimals ERC-20 Permit signatures Maximum price per booking ### Purchase Ad Slot (x402 Payment) ```bash POST https://x402.anyspend.com/ads/buy ``` Programmatically purchase ad slots using x402 gasless payments. This endpoint requires x402 payment authorization. **Request Body:** ```json Request { "productId": "slot_abc123", "buyerAddress": "0x742d35Cc6...", "startTime": "2025-01-15T14:00:00Z", "endTime": "2025-01-15T18:00:00Z", "adContent": { "imageUrl": "https://...", "linkUrl": "https://...", "altText": "Alt text", "title": "Ad title", "description": "Description" } } ``` ```json Success Response (200) { "success": true, "data": { "purchaseId": "purch_123...", "bookingId": "booking_456...", "totalPrice": "5000000", "status": "confirmed" } } ``` ```json Error Response (400) { "success": false, "error": "Slot already booked during this time" } ``` **Parameters:** - `productId` (required) - The ad slot ID from `/ads/slots` - `buyerAddress` (required) - Your wallet address - `startTime` (required) - Start time in ISO 8601 format - `endTime` (required) - End time in ISO 8601 format - `adContent.imageUrl` (required) - Direct URL to ad image - `adContent.linkUrl` (required) - Landing page URL - `adContent.altText` (required) - Image alt text - `adContent.title` (optional) - Ad title - `adContent.description` (optional) - Ad description **JavaScript/TypeScript Example:** ```typescript import { wrapFetchWithPayment } from '@b3dotfun/anyspend-x402-fetch'; import { createWalletClient, custom, publicActions } from 'viem'; import { base } from 'viem/chains'; // Create wallet client const walletClient = createWalletClient({ account: '0x742d35Cc6...', chain: base, transport: custom(window.ethereum), }).extend(publicActions); // Wrap fetch with x402 payment const fetchWithPayment = wrapFetchWithPayment( fetch, walletClient, BigInt(1000 * 10 ** 6) // Max 1000 USDC ); // Purchase ad slot const response = await fetchWithPayment( 'https://x402.anyspend.com/ads/buy', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ productId: 'slot_abc123', buyerAddress: '0x742d35Cc6...', startTime: '2025-01-15T14:00:00Z', endTime: '2025-01-15T18:00:00Z', adContent: { imageUrl: 'https://example.com/ad.jpg', linkUrl: 'https://example.com', altText: 'My ad', title: 'Check out our product!', description: 'Limited offer' } }) } ); const result = await response.json(); console.log('Booking ID:', result.data.bookingId); ``` See [x402 SDK documentation](/anyspend/x402-overview) for more details on using `wrapFetchWithPayment`. ### Browse Sites (Free) ```bash GET https://x402.anyspend.com/ads/sites ``` List all available sites with pagination. This endpoint is free to call. Query parameters: - `page` - Page number (default: 1) - `limit` - Results per page (default: 20, max: 100) - `search` - Search by name/domain/keywords ```bash cURL curl "https://x402.anyspend.com/ads/sites?search=defi&limit=10" ``` ```javascript JavaScript const sites = await fetch('https://x402.anyspend.com/ads/sites?page=1&limit=20') .then(r => r.json()); ``` ```json Response { "success": true, "data": [ { "siteId": "abc123", "siteName": "Crypto News Daily", "siteUrl": "https://cryptonews.example.com", "siteDomain": "cryptonews.com", "description": "Daily crypto news and analysis", "keywords": ["crypto", "bitcoin", "defi"], "availableSlots": ["leaderboard", "sidebar", "banner"], } ], "pagination": { "page": 1, "limit": 20, "total": 156, "hasNext": true } } ``` ### List All Slots (Free) ```bash GET https://x402.anyspend.com/ads/slots ``` List all available ad slots across all sites. This endpoint is free to call. ```bash cURL curl "https://x402.anyspend.com/ads/slots" ``` ```javascript JavaScript const slots = await fetch('https://x402.anyspend.com/ads/slots') .then(r => r.json()); ``` ```json Response { "success": true, "data": [ { "slotId": "slot_abc123", "siteId": "site_123", "slotType": "leaderboard", "pricePerHour": "5000000" } ] } ``` ### Get Slot Details (Free) ```bash GET https://x402.anyspend.com/ads/slots/:slotId ``` Returns static slot information including pricing, format, and associated site details. This endpoint is free to call. ```bash cURL curl "https://x402.anyspend.com/ads/slots/slot_banner_abc123" ``` ```json Response { "success": true, "data": { "slot": { "slotId": "slot_banner_abc123", "siteId": "abc123", "slotType": "banner", "pricePerHour": "1000000", "available": true }, "site": { "siteName": "Crypto News Daily", "siteUrl": "https://cryptonews.example.com" } } } ``` ### Check Current Ad (Free) ```bash GET https://x402.anyspend.com/ads/slots/:slotId/current-ad ``` Returns the ad currently running in this slot, or indicates if the slot is available. This endpoint is free to call. ```bash cURL curl "https://x402.anyspend.com/ads/slots/slot_banner_abc123/current-ad" ``` ```json Ad Running { "success": true, "data": { "type": "paid", "ad": { "imageUrl": "https://example.com/ad.png", "linkUrl": "https://example.com/landing" }, "booking": { "bookingId": "booking_xyz789", "startTime": "2024-02-01T10:00:00.000Z", "endTime": "2024-02-01T13:00:00.000Z" } } } ``` ```json Slot Available { "success": true, "data": { "type": "empty" } } ``` ### View Your Campaigns (Free) ```bash GET https://x402.anyspend.com/ads/bookings/buyer/:address ``` Track all your ad bookings - active, pending, and completed. This endpoint is free to call. ```bash cURL curl "https://x402.anyspend.com/ads/bookings/buyer/0xYourAddress" ``` ```json Response { "success": true, "data": [ { "bookingId": "booking_xyz789", "siteId": "abc123", "slotType": "banner", "startTime": "2024-02-01T10:00:00.000Z", "endTime": "2024-02-01T13:00:00.000Z", "adContent": { "imageUrl": "https://mysite.com/ad.png", "linkUrl": "https://mysite.com/landing" }, "totalPrice": "3000000", "status": "active", "paymentTxHash": "0xabcdef...", "createdAt": "2024-01-22T16:30:00.000Z" } ] } ``` **Status values:** - `active` - Currently running - `pending` - Scheduled for future - `completed` - Campaign ended Prices in API responses are in USDC wei (6 decimals). Divide by 1,000,000 to get USDC amount. --- ## Article Submission Endpoints ### Validate Article Idea (Free) ```bash POST https://x402.anyspend.com/articles/validate ``` Validate an article idea and get AI-generated title and description. This endpoint is free to call - no payment required. **Request Body:** ```json Request { "siteDomain": "baseradar.com", "userInput": "How to Use Base Pay for Creators in Your DApp" } ``` ```json Approved Response (Score ≥70) { "success": true, "data": { "approved": true, "score": 92, "reasoning": "Excellent topic match for Base ecosystem content", "estimatedPrice": "15000000", "suggestedTitle": "How to Use Base Pay for Creators in Your DApp", "suggestedDescription": "Learn how to integrate Base Pay...", "userProvidedTitle": true, "message": "Your input is approved as-is" } } ``` ```json Rejected Response (Score <70) { "success": false, "data": { "approved": false, "score": 45, "reasoning": "Topic doesn't align with site's focus on Base ecosystem", "estimatedPrice": "15000000", "message": "Content doesn't fit the site's focus" } } ``` **Parameters:** - `siteDomain` (required) - Target site domain (e.g., "baseradar.com", "solanaecho.com") - `userInput` (required) - Can be: - Complete article title (10-200 characters) - Tweet URL (e.g., "https://x.com/username/status/...") - Topic or idea (e.g., "base pay for creators") **AI Scoring:** - **Score ≥80:** Your input is perfect! Used as-is - **Score 70-79:** Good content, AI provides improved suggestions - **Score <70:** Rejected - topic doesn't fit the site **JavaScript Example:** ```javascript const response = await fetch('https://x402.anyspend.com/articles/validate', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ siteDomain: 'baseradar.com', userInput: 'How to bridge assets to Base chain' }) }); const result = await response.json(); console.log('Approved:', result.data.approved); console.log('Score:', result.data.score); console.log('Title:', result.data.suggestedTitle); ``` ### Submit Article Request (x402 Payment) ```bash POST https://x402.anyspend.com/articles/buy ``` Submit an article request with x402 gasless payment. Requires prior validation approval. **Request Body:** ```json Request { "buyerAddress": "0x742d35Cc6...", "siteDomain": "baseradar.com", "title": "How to Use Base Pay for Creators in Your DApp", "description": "Learn how to integrate Base Pay into your decentralized application..." } ``` ```json Success Response (200) { "success": true, "data": { "requestId": "req_abc123...", "productSpecificId": "req_abc123...", "totalPrice": "15000000", "status": "pending" } } ``` ```json Error Response (400) { "success": false, "error": "Title is required and must be 10-200 characters" } ``` **Parameters:** - `buyerAddress` (required) - Your wallet address - `siteDomain` (required) - Target site domain - `title` (required) - Article title (10-200 characters) - `description` (required) - Article description/summary **JavaScript/TypeScript Example:** ```typescript import { wrapFetchWithPayment } from '@b3dotfun/anyspend-x402-fetch'; import { createWalletClient, custom, publicActions } from 'viem'; import { base } from 'viem/chains'; // Create wallet client const walletClient = createWalletClient({ account: '0x742d35Cc6...', chain: base, transport: custom(window.ethereum), }).extend(publicActions); // Wrap fetch with x402 payment const fetchWithPayment = wrapFetchWithPayment( fetch, walletClient, BigInt(1000 * 10 ** 6) // Max 1000 USDC ); // Submit article request const response = await fetchWithPayment( 'https://x402.anyspend.com/articles/buy', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ buyerAddress: '0x742d35Cc6...', siteDomain: 'baseradar.com', title: 'How to Use Base Pay for Creators in Your DApp', description: 'Learn how to integrate Base Pay into your decentralized application for seamless creator payments.' }) } ); const result = await response.json(); console.log('Request ID:', result.data.requestId); ``` ### View Your Article Requests (Free) ```bash GET https://x402.anyspend.com/articles/requests/buyer/:address ``` Track all your article requests - pending, in progress, and published. This endpoint is free to call. ```bash cURL curl "https://x402.anyspend.com/articles/requests/buyer/0xYourAddress" ``` ```json Response { "success": true, "data": [ { "requestId": "req_abc123", "siteName": "Base Radar", "siteDomain": "baseradar.com", "title": "How to Use Base Pay for Creators", "description": "Learn how to integrate Base Pay...", "totalPrice": "15000000", "status": "published", "publishedUrl": "https://baseradar.com/articles/base-pay-creators", "createdAt": "2025-01-15T10:00:00.000Z", "updatedAt": "2025-01-16T15:30:00.000Z" } ] } ``` **Status values:** - `pending` - Waiting for site to write article - `in_progress` - Article is being written - `published` - Article is live (includes `publishedUrl`) - `rejected` - Article request was declined --- ## Zero Gas with x402 x402 is the payment protocol that makes crypto payments feel like web2. **Traditional crypto payments:** - ❌ Multiple transactions (approve + transfer) - ❌ $5-15 in gas fees - ❌ 30-60 second wait times - ❌ Complex multi-step flows **With x402:** - ✅ One signature - no transactions - ✅ Zero gas fees - ✅ Instant settlement - ✅ Simple one-click purchase ### How It Works 1. You sign a payment authorization message (not a transaction) 2. x402 facilitator submits the transaction for you 3. Facilitator pays the gas 4. You pay only the ad price Always verify the amount and recipient before signing! ### Security - ✅ You control the signature - ✅ Signatures expire (can't be replayed) - ✅ One-time use with unique nonce - ✅ Amount is locked (can't charge more) ## Tips for Success **Design Eye-Catching Ads** - Use high contrast colors - Keep text large and readable - Include a clear call-to-action - Test image URL before booking **Target the Right Audience** - Match sites to your target market - Check traffic stats before booking - Consider multiple smaller sites vs one large site **Track Performance** Use UTM parameters in your landing page URL: ``` https://yoursite.com?utm_source=sitename&utm_medium=banner ``` **Start Small & Scale** - Book 1-2 hours first to test - Monitor click-through rates - Scale up what works **Writing Effective Article Titles** - Keep titles between 10-200 characters - Be specific and descriptive - Match the site's content focus - Use keywords relevant to the site's audience - If you have a great title, submit it directly (10+ chars) **Maximize Article Approval** - Research the site before submitting - Check recent articles for tone and topics - Tweet URLs work great - AI extracts context - Validate multiple ideas before paying - Score ≥70 required for approval **Leverage AI Suggestions** - If score is 70-89, review AI improvements - AI optimizes for SEO and engagement - Suggested descriptions enhance your submission - Use validation to refine your pitch ## Common Issues **'Insufficient balance' error** You need USDC on Base network. Check that: - You're connected to Base (Chain ID: 8453) - You have enough USDC for the total cost **'Time slot unavailable' error** Someone just booked that slot. Refresh and choose a different time. **Can I cancel a booking?** Currently, bookings cannot be cancelled or refunded. Make sure your ad is ready before booking. **Can I edit my ad after booking?** No, ad content is locked at booking time. You'll need to make a new booking to change it. **[Launch Your Campaign](https://explorer.b3.fun/apps/x402-ad-marketplace)** Start advertising on crypto sites in 5 minutes --- **Related:** [Article Submission Marketplace](/anyspend/marketplace-articles) • [x402 Overview](/anyspend/x402-overview) • [x402scan →](https://www.x402scan.com/server/ff37cb5f-7976-42bb-a161-e5e360d8cd42)