# web4shop — x402 Paid API Services

> Pay-per-call API endpoints for AI agents, settled in USDC on Base via the x402 protocol (HTTP 402). No API keys, no signup. Each endpoint returns a machine-payable 402 challenge; an agent with a funded Base wallet pays and retries to receive JSON. Mainland-China vantage probes are exclusive to this store.

## Catalog (101 products)

- [DNS Record Lookup — A/AAAA/MX/TXT/NS via DoH](https://web4shop-x402.web4shop-7023.workers.dev/api/products/dns-lookup): $0.001 USDC — tools
- [HTTP Health Check — Status, Latency, SSL, Redirects](https://web4shop-x402.web4shop-7023.workers.dev/api/products/health-check): $0.001 USDC — tools
- [Umbrella — Web4 Original Digital Work](https://web4shop-x402.web4shop-7023.workers.dev/api/products/umbrella): $0.01 USDC — digital-art
- [Agent Bulletin Board — post an announcement, crawled by Bing (30 days)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/bulletin-post): $0.01 USDC — social
- [URL to Markdown — Clean Text Extraction from Any Webpage](https://web4shop-x402.web4shop-7023.workers.dev/api/products/url-to-markdown): $0.01 USDC — tools
- [Mainland China Reachability Check — Live Probe (any URL)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/reachability-live): $0.02 USDC — data
- [JWT Decoder — Decode Header + Payload Without Verification](https://web4shop-x402.web4shop-7023.workers.dev/api/products/jwt-decode): $0.02 USDC — tools
- [Mainland China Network Reachability Digest — Dev & AI Infrastructure](https://web4shop-x402.web4shop-7023.workers.dev/api/products/cn-reachability-digest): $0.05 USDC — data
- [Webpage Summary — Title, Description, Keywords, Body Extract](https://web4shop-x402.web4shop-7023.workers.dev/api/products/summarize-api): $0.05 USDC — tools
- [Agent Registry — Register and Discover AI Agents](https://web4shop-x402.web4shop-7023.workers.dev/api/products/agent-registry): $0.05 USDC — tools
- [Redirect Chain Tracer — Full Hop-by-Hop Analysis with Timing](https://web4shop-x402.web4shop-7023.workers.dev/api/products/redirect-tracer): $0.05 USDC — tools
- [IP Information — Geolocation, ASN, Organization, Timezone](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ip-info): $0.05 USDC — tools
- [LLM Text Generation Pro — GPT-OSS 120B High-Quality Reasoning](https://web4shop-x402.web4shop-7023.workers.dev/api/products/llm-generate-pro): $0.05 USDC — ai
- [WHOIS Domain Lookup — Registration, Expiry, Registrar via RDAP](https://web4shop-x402.web4shop-7023.workers.dev/api/products/whois-lookup): $0.1 USDC — tools
- [robots.txt Compliance Check — Crawl Rules & SEO Audit](https://web4shop-x402.web4shop-7023.workers.dev/api/products/robots-txt-check): $0.1 USDC — tools
- [Proof of Existence — Content Hash + Timestamp on KV](https://web4shop-x402.web4shop-7023.workers.dev/api/products/proof-of-existence): $0.1 USDC — tools
- [API Scanner — x402 & Security Analysis](https://web4shop-x402.web4shop-7023.workers.dev/api/products/api-scan): $0.1 USDC — tools
- [Website Tech Stack Fingerprint — Framework, CMS, Hosting, Analytics](https://web4shop-x402.web4shop-7023.workers.dev/api/products/tech-stack-scan): $0.1 USDC — intelligence
- [动画解题：HL 全等证明（中线+垂直） — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-hl-triangle-congruence): $0.1 USDC — education
- [动画解题：一次函数与不等式（数形结合） — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-linear-function-inequality): $0.1 USDC — education
- [动画解题：二次函数最值（配方法） — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-quadratic-maxmin): $0.1 USDC — education
- [动画解题：功和机械效率（滑轮组） — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-work-mechanical-efficiency): $0.1 USDC — education
- [动画解题：将军饮马 — 最短路径问题 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-general-horse-water): $0.1 USDC — education
- [动画解题：文言文翻译（逐字解析法） — 初中语文解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-classical-chinese-translation): $0.1 USDC — education
- [动画解题：溶解度曲线 — 析出晶体 — 初中化学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-solubility-crystal): $0.1 USDC — education
- [动画解题：英语完形填空（上下文推理法） — 初中英语解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-english-cloze-context): $0.1 USDC — education
- [动画解题：滑轮组机械效率（额外功变式） | 初中八年级 education解题动画（原创分步）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/pulley-efficiency-variant): $0.1 USDC — education
- [动画解题：化学方程式计算（质量守恒与过量判断） | 初中九年级 education解题动画（原创分步）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/chem-conservation-variant): $0.1 USDC — education
- [SSL Certificate Check — Expiry, Issuer, Chain Validation](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ssl-cert-check): $0.15 USDC — tools
- [Security Headers Check — CSP, HSTS, CORS, X-Frame-Options Audit](https://web4shop-x402.web4shop-7023.workers.dev/api/products/security-headers-check): $0.15 USDC — tools
- [DNSSEC Validation — Verify DNS Security Extensions](https://web4shop-x402.web4shop-7023.workers.dev/api/products/dnssec-check): $0.15 USDC — tools
- [Web Performance Analyzer — TTFB + Resources + Cache + DOM Analysis](https://web4shop-x402.web4shop-7023.workers.dev/api/products/performance-analyzer): $0.15 USDC — tools
- [Structured Data Extractor — JSON-LD + Microdata + Schema.org Types](https://web4shop-x402.web4shop-7023.workers.dev/api/products/structured-data-extractor): $0.15 USDC — tools
- [Agentic Readiness Audit — AI Crawler & Machine-Payable Check](https://web4shop-x402.web4shop-7023.workers.dev/api/products/agentic-readiness-audit): $0.15 USDC — tools
- [Technical SEO Audit — On-Page Health Check (no external links/keywords)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/seo-tech-audit): $0.15 USDC — seo
- [Office Autopilot — 本地办公自动化·批量文档/表格处理操作包](https://web4shop-x402.web4shop-7023.workers.dev/api/products/office-autopilot): $0.19 USDC — business
- [Broken Links Check — Dead Link Scanner for Any URL](https://web4shop-x402.web4shop-7023.workers.dev/api/products/broken-links-check): $0.2 USDC — tools
- [Geo Restriction Check — Detect Geographic Content Differences](https://web4shop-x402.web4shop-7023.workers.dev/api/products/geo-restriction-check): $0.2 USDC — tools
- [OFAC Sanctions Screening — wallet address or name vs SDN list](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ofac-screen): $0.25 USDC — data
- [Page Change Monitor — Detect Website Content Changes](https://web4shop-x402.web4shop-7023.workers.dev/api/products/page-change-monitor): $0.25 USDC — tools
- [Email Authentication Audit — SPF + DKIM + DMARC Full Analysis](https://web4shop-x402.web4shop-7023.workers.dev/api/products/email-auth-check): $0.25 USDC — tools
- [x402 Bundle Builder — Multi-Product Pricing + Code Snippets](https://web4shop-x402.web4shop-7023.workers.dev/api/products/x402-bundle-builder): $0.25 USDC — x402-tools
- [动画解题：一线三等角模型（K型） — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-one-line-three-angles): $0.25 USDC — education
- [动画解题：倍长中线法 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-midline-doubling): $0.25 USDC — education
- [动画解题：动态电路分析（滑动变阻器） — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-dynamic-circuit-slider): $0.25 USDC — education
- [动画解题：化学方程式计算（过量判断） — 初中化学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-chemical-equation-calc): $0.25 USDC — education
- [动画解题：固体压强叠加体 — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-solid-pressure-stack): $0.25 USDC — education
- [动画解题：圆的切线证明题 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-circle-tangent-proof): $0.25 USDC — education
- [动画解题：赵爽弦图 — 勾股定理证明 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-zhao-shuang-diagram): $0.25 USDC — education
- [动画解题：截长补短法 — 梯形等积分割 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-segment-compensation): $0.25 USDC — education
- [动画解题：手拉手模型 — 共顶点旋转 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-hand-in-hand-rotation): $0.25 USDC — education
- [动画解题：杠杆平衡（力臂分析） — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-lever-balance): $0.25 USDC — education
- [动画解题：浮力变化 — 阿基米德原理 — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-archimedes-buoyancy): $0.25 USDC — education
- [动画解题：热平衡计算（比热容） — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-heat-balance-specific-heat): $0.25 USDC — education
- [动画解题：电路开关通断分析 — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-circuit-switch): $0.25 USDC — education
- [动画解题：等腰直角三角形旋转 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-isosceles-rt-rotation): $0.25 USDC — education
- [动画解题：透镜成像规律（光路图） — 初中物理解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-lens-ray-diagram): $0.25 USDC — education
- [动画解题：金属与酸反应 — 气泡动画 — 初中化学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-metal-acid-reaction): $0.25 USDC — education
- [《HL全等证明-中线垂直》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-hl-triangle-congruence): $0.25 USDC — education
- [《倍长中线法》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-midline-doubling): $0.25 USDC — education
- [《文言文翻译-逐字解析》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-classical-chinese-translation): $0.25 USDC — education
- [《浮力变化-阿基米德》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-archimedes-buoyancy): $0.25 USDC — education
- [《溶解度曲线-析出晶体》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-solubility-crystal): $0.25 USDC — education
- [《英语完形填空-上下文推理》解题微课（配音版 mp4）— 原创初中解题动画](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-mp4-english-cloze-context): $0.25 USDC — education
- [Prospector Intl — 外贸/实体厂找买家·找卖家·资源搜索操作手册（生成式交付包）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/prospector-intl): $0.29 USDC — business
- [OpenAPI Validate — Swagger/OpenAPI Spec Compliance Checker](https://web4shop-x402.web4shop-7023.workers.dev/api/products/openapi-validate): $0.3 USDC — tools
- [二次函数最值（顶点式-平移变式）动画精讲 — 原创讲义Word + HTML分步动画 + 配音 + 可打印SVG](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-quadratic-shift): $0.3 USDC — education
- [滑轮组机械效率（三段绳变式）动画精讲 — 原创讲义Word + HTML分步动画 + 配音 + 可打印SVG](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-pulley-three-rope): $0.3 USDC — education
- [化学方程式计算（恰好反应变式）动画精讲 — 原创讲义Word + HTML分步动画 + 配音 + 可打印SVG](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-chem-stoich-exact): $0.3 USDC — education
- [Design Taste Guard — AI 前端设计品味·反平庸上线前检查包（反 AI slop 决策路由）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/design-taste-guard): $0.35 USDC — business
- [AI Eng Toolkit — AI 结对工程·8 大工作流决策路由速查包](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ai-eng-toolkit): $0.39 USDC — business
- [初中化学计算专题动画讲义（方程式过量判断）— 原创 Word + HTML 分步动画 + SVG](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-chemistry-calculations): $0.39 USDC — education
- [生产力计划表/追踪器 schema 操作包 (Planner & Tracker Schema Kit)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/planner-schema-kit): $0.39 USDC — business
- [Site Security Audit Bundle — SSL + Headers + Broken Links](https://web4shop-x402.web4shop-7023.workers.dev/api/products/site-security-audit): $0.4 USDC — tools
- [MCP Builder Kit — MCP 服务搭建·工具设计·评测全流程操作包（给 AI 同事用的接口规范）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/mcp-builder-kit): $0.45 USDC — business
- [Research Submission Kit — 科研论文投稿全流程操作包（写作纪律·审稿回复·统计核验·配图规范）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/research-submission-kit): $0.49 USDC — business
- [初中数学几何模型动画精讲合集（将军饮马/弦图/倍长中线…）— 原创讲义Word + HTML分步动画 + 可打印SVG](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-geometry-animations): $0.49 USDC — education
- [初中物理力学专题动画讲义（浮力/阿基米德原理）— 原创 Word + HTML 分步动画 + SVG + 配音](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-physics-forces): $0.49 USDC — education
- [AI 漫剧/短视频分镜脚本操作包 (AI-Video Storyboard Kit)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ai-video-storyboard-kit): $0.49 USDC — business
- [PPT/幻灯片生成操作包 (Slide-Deck Builder Kit)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ppt-deck-builder-kit): $0.49 USDC — business
- [Safety Scanner — API Vulnerability Assessment](https://web4shop-x402.web4shop-7023.workers.dev/api/products/safety-scan): $0.5 USDC — tools
- [x402 Merchant Worker Template — AI-Generated Custom Code](https://web4shop-x402.web4shop-7023.workers.dev/api/products/x402-merchant-template): $0.5 USDC — x402-tools
- [动画解题：旋转构造全等三角形 — 初中数学解题动画（原创）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/edu-anim-rotation-congruence): $0.5 USDC — education
- [AI 提示词工程操作包 (AI-Prompt Engineering Kit)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/ai-prompt-engineering-kit): $0.59 USDC — business
- [Brand Typosquat Scanner — Candidate Lookalike Domain Generator](https://web4shop-x402.web4shop-7023.workers.dev/api/products/typo-scan): $0.6 USDC — security
- [Verigrace Protocol Readiness Scan — Public x402 Endpoint Evidence](https://web4shop-x402.web4shop-7023.workers.dev/api/products/agent-launch-scan): $0.75 USDC — web4-agent-infrastructure
- [Supplier Onboarding Compliance Check — OFAC + Email + SSL + Headers in One Report](https://web4shop-x402.web4shop-7023.workers.dev/api/products/onb-supplier-check): $0.75 USDC — compliance
- [HotSpot AI Photo Enhancement Pack — Pipeline + 10 Preset Recipes](https://web4shop-x402.web4shop-7023.workers.dev/api/products/hotspot-ai-photo-enhance): $0.99 USDC — ai-tools
- [A2A 全自动卖货机搭建蓝图 (A2A Vending-Machine Blueprint)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/a2a-vending-machine-blueprint): $0.99 USDC — business
- [x402 Endpoint Compliance Audit Pro — 14-Point Instant Check](https://web4shop-x402.web4shop-7023.workers.dev/api/products/x402-audit-pro): $1 USDC — data
- [Agent Launch Scout — AI-Powered Site Intelligence (SEO + Security + Performance)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/agent-launch-scout): $1.5 USDC — site-intelligence
- [Dev Tools Bundle — 15 合一开发者工具包（$1.99 一次买断 vs 单价 $1.28）](https://web4shop-x402.web4shop-7023.workers.dev/api/products/dev-tools-bundle): $1.99 USDC — tools
- [x402 Wrap Generator — turn YOUR plain API into a sellable x402 endpoint (custom code package)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/x402-wrap-generator): $2 USDC — tools
- [HotSpot Daily Intelligence Digest — Scoring Model + Alert Blueprint](https://web4shop-x402.web4shop-7023.workers.dev/api/products/hotspot-digest): $2.99 USDC — intelligence
- [Verigrace Release Evidence Pack — Commit-Ready x402 Artifacts](https://web4shop-x402.web4shop-7023.workers.dev/api/products/agent-launch-pack): $4.9 USDC — web4-agent-infrastructure
- [Verigrace Skill License — Perpetual Core](https://web4shop-x402.web4shop-7023.workers.dev/api/products/planforge-skill-license): $9 USDC — tools
- [HotSpot B2B Opportunity Report — Six-Platform Lead Workflow Kit](https://web4shop-x402.web4shop-7023.workers.dev/api/products/hotspot-b2b-report): $9.99 USDC — b2b-intelligence
- [A2A-x402 Compliance Audit — Enterprise Agent Payment Readiness Report](https://web4shop-x402.web4shop-7023.workers.dev/api/products/a2a-x402-audit): $10 USDC — x402-tools
- [AI 落地页快速版 — 24h 交付单页(模板化)](https://web4shop-x402.web4shop-7023.workers.dev/api/products/landing-page-express): $19 USDC — business-service
- [AI 企业落地页服务 — 单页商业网站(中文/英文) + SEO 关键词](https://web4shop-x402.web4shop-7023.workers.dev/api/products/landing-page-service): $49 USDC — business-service

## Optional

- [Machine-readable x402 manifest](https://web4shop-x402.web4shop-7023.workers.dev/.well-known/x402.json)
- [OpenAPI spec](https://web4shop-x402.web4shop-7023.workers.dev/openapi.json)
- [Agent card (A2A)](https://web4shop-x402.web4shop-7023.workers.dev/.well-known/agent.json)
- [Full catalog JSON](https://web4shop-x402.web4shop-7023.workers.dev/api/products)