x402 paid APIs: MCP servers, A2A agents and x402 APIs

• roastx402endpoint.vercel.app Live x402

  Pay for a lighthearted developer roast generated on-demand.

  x402 paid API · 1 endpoint

• robbiegeorgephotography.com Live x402

  Atomic canonical resolution for the registered Robbie George Biography Plate™ identifier. x402 payment grants one endpoint-level retrieval only. It does not grant training, embedding, bulk ingestion, redistribution, res…

  x402 paid API · 1 endpoint

• router.mudko.com Live x402

  OnRamperX is a non-custodial value router for agents and humans: fiat<->crypto and cross-chain via one quote interface (Coinbase Onramp v2, Relay, x402). This endpoint returns the router's live capabilities and rail sta…

  x402 paid API · 1 endpoint

• rtt.phoenix-ai.work Live x402

  Boolean pre-flight check for L2 transaction safety across all 12 chains (?chain= param, default: base). Returns safe=true/false with reason code. Revert ratio data available for Base and Arbitrum only (eth_getBlockRecei…

  x402 paid API · 5 endpoints

• rugsense.xyz Live x402

  Scored intelligence on freshly-launched Base tokens: safety + momentum → composite score and an AVOID/WATCH/HOT decision per launch. One call returns a ranked list.

  x402 paid API · 1 endpoint

• run402.com Live x402

  Set prototype tier ($0.10 USDC) — auto-detects start/renew/upgrade

  x402 paid API · 1 endpoint

• rxatlas.dev Live x402

  Search US drug products by NDC, brand, generic name, ingredient, manufacturer, dosage form, route, source, or identifier.

  x402 paid API · 1 endpoint

• safe.cyberwarex.com Live x402

  Score a URL for phishing risk before an agent opens or trusts it. Keyless, deterministic heuristics - typosquat / homoglyph of a known brand, punycode / mixed-script hosts, credentials-in-URL, raw-IP hosts, suspicious T…

  x402 paid API · 1 endpoint

• ScalpStream Research Live A2A

  Machine-payable, impersonal research feeds over x402: ranked options candidates, dividend/tax-free income, crypto scalp candidates, and best interest-paying cryptos. Built to be polled: free previews carry a judgeable s…

  A2A agent · ScalpStream Research · 4 skills

• scan.openverbs.com Live x402

  Scan source code or configuration text for hardcoded secrets: AWS access keys, GitHub/Slack/Google tokens, Stripe and OpenAI keys, PEM private-key blocks, JWTs and high-entropy secret assignments. Placeholder values are…

  x402 paid API · 4 endpoints

• schema.nsgoods.org Live x402

  Signed extractability score (0-100) + breakdown + fixes for a URL. Free preview: GET /extractability/preview Blocked or bad input returns 400; a failed fetch returns 502; you are never charged for an error.

  x402 paid API · 1 endpoint

• scopeapi.dev Live x402

  Generate text embeddings and semantic embedding vectors using OpenAI text-embedding-3-small for vector search, semantic similarity, clustering, retrieval, and RAG workflows. (12 paid endpoints on scopeapi.dev.)

  x402 paid API · 12 endpoints

• scout.hugen.tokyo Live x402

  11-source parallel intelligence report in one call — HN, GitHub, npm, PyPI, Dev.to, Hashnode, Lobsters, StackExchange, ArXiv, Semantic Scholar, GitLab. Best ROI on Bazaar. AI agent API for market research. Accepts USDC…

  x402 paid API · 12 endpoints

• screenshot-api-production-fe7e.up.railway.app Live x402

  Render an http(s) URL to a PDF (A4/A3/Letter/Legal/Tabloid) with print emulation; returns a JSON envelope with the PDF base64-encoded under pdf_base64, plus final_url, title, format, and size. (2 paid endpoints on scree…

  x402 paid API · 2 endpoints

• scribe.vimabrosta.com Live x402

  Look up a domain: registration data from RDAP (registrar, created, expires, status, nameservers), live DNS records (A, AAAA, MX, NS, TXT, CNAME), the TLS certificate served at the name (issuer, validity, alternative nam…

  x402 paid API · 4 endpoints

• SCRIPTMASTERLABS — SqueezeOS Trust Router Live A2A

  Read-only A2A control-plane agent for live SqueezeOS capability discovery, external provider Trust Passports, recommendation, inspection, runtime status, x402 readiness, settlement evidence, durable historical behavior…

  A2A agent · Script Master Labs, LLC · 9 skills

• scrooge-x402-tool-mill.vercel.app Live x402

  Extract schema.org structured data from a public HTML page: JSON-LD (@graph flattened), top-level microdata, and Open Graph / Twitter meta. Normalizes Product/Offer, Article, Organization, Event, FAQ, and breadcrumbs. P…

  x402 paid API · 8 endpoints

• SCVD Evidence Agent Live A2A

  scvd.store is an evidence observatory for agentic commerce — x402 today, cross-protocol by design: independent signed observation of what other people's endpoints, artifacts and payments actually did, with the gaps coun…

  A2A agent · Record Creative Co. LLC · 3 skills

• scvd.store Live x402

  Spot Check. REQUIRES ?host= on the paid request — a signed request without it is refused before the gate and no money moves. Name a host and get what this observatory already holds on it, signed: corpus rounds and verdi…

  x402 paid API · 12 endpoints

• search.cyberwarex.com Live x402

  Web search that returns structured SERP results as JSON. Runs on a dedicated SearXNG instance aggregating multiple engines, so there is no per-engine API key, quota or HTML scraping to manage. Each result carries title,…

  x402 paid API · 5 endpoints

• search.openverbs.com Live x402

  Wikipedia summary API - the plain-language summary of the best-matching Wikipedia article for a topic or query, in any language. Returns the article title, short description, summary extract, thumbnail image and canonic…

  x402 paid API · 10 endpoints

• Second Eyes Agent Workflow Services Live MCP

  Workflow diagnostics, capability routing, and x402 settlement for MCP-compatible agents.

  MCP server · io.github.This-Is-Hellgate

• sec.use.x402atlas.com Live x402

  SEC company financials by ticker — normalized annual and quarterly revenue, income, balance-sheet, cash-flow and EPS facts. (3 paid endpoints on sec.use.x402atlas.com.)

  x402 paid API · 3 endpoints

• seerium.xyz Live x402

  Macro market signals API for agents. Tracks inflation, rates, liquidity, economic releases, crypto, and prediction markets. (26 paid endpoints on api.seerium.xyz.)

  x402 paid API · 12 endpoints

• semver.openverbs.com Live x402

  Parse a semantic version into major/minor/patch, prerelease and build metadata. (3 paid endpoints on semver.openverbs.com.)

  x402 paid API · 3 endpoints

• sentiment.openverbs.com Live x402

  Market & brand sentiment for any keyword, brand, ticker or product: analyses the sentiment of web & news content mentioning it and returns an overall label (positive/negative/neutral/mixed), a net sentiment score (-1..1…

  x402 paid API · 1 endpoint

• sentinel.rootstuff.io Live x402

  Every DNS record for a domain plus propagation across public resolvers (7 paid endpoints on sentinel.rootstuff.io.)

  x402 paid API · 7 endpoints

• seo-data-extractor.underscoredone.com Live x402

  Give this API a web address and it will visit that page, then hand back everything an SEO professional needs to know: the page title, meta description, meta keywords, robots instructions, canonical link, H1/H2/H3 headin…

  x402 paid API · 1 endpoint

• seo.forgemesh.io Live x402

  Correct likely spelling errors in an SEO query (2 paid endpoints on seo.forgemesh.io.)

  x402 paid API · 2 endpoints

• seo.halowerk.com Live x402

  Title present audit fetches current public evidence from the supplied target and evaluates the documented criterion. It returns the observation, threshold, verdict, exact evidence source, limitations and a mode-specific…

  x402 paid API · 5 endpoints

• seo.openverbs.com Live x402

  Domain overview: estimate a domain's Google SEO footprint — total organic and paid keywords, estimated traffic (ETV), traffic cost, and how many keywords rank in the top 3, top 10 and top 100. Fast website and domain SE…

  x402 paid API · 12 endpoints

• seoul-weather-402.fly.dev Live x402

  Real-time Seoul weather — temperature, sky, humidity, wind (KMA official data)

  x402 paid API · 1 endpoint

• serp402.com Live x402

  Google search for agents, paid per call: web, news, images, videos, places, shopping and Scholar, all returned in one shape with canonicalised URLs, duplicates removed and dates normalised to ISO. Direct answers and kno…

  x402 paid API · 1 endpoint

• settled.tools Live x402

  Signed check of an x402 endpoint before you pay it: who really pays it on Base (settlements and unique payers over 30 days), a fresh unpaid probe (cached ≤5 min) with status, latency and the parsed quote, payability, pa…

  x402 paid API · 8 endpoints

• sftunes.com Live x402

  SFtunes catalog for agents: index of public mixtapes and public Top 10 lists, or one item with liner notes and music-service links via ?id=<uuid> (tape) or ?id=top10-<handle> (a person's Top 10 + Side B).

  x402 paid API · 1 endpoint

• sg-cm-kg.ai Live x402

  One paid call on sg-cm-kg.ai for $0.01 USDC: the surface's own statement of record (a market node: its list_nodes line; a product: its record of record; allooloo.io: the estate scale block), public-record only, with an…

  x402 paid API · 1 endpoint

• sh-origin.walls.sh Live x402

  Real-time news search for AI agents. Returns recent news articles (title, link, snippet, published date) as JSON from a multi-engine news metasearch. Pay-per-query in USDC via x402 — no signup, no API key. Use for curre…

  x402 paid API · 4 endpoints

• shared-hold-api.onrender.com Live x402

  Store payload to Shared Hold boundary - 0.005 USDC per successful hold

  x402 paid API · 1 endpoint

• shield.vainplex.dev Live x402

  ShieldAPI - x402 security preflight before agents accept or store credential material (3 paid endpoints on shield.vainplex.dev.)

  x402 paid API · 3 endpoints

• shizu.me Live x402

  Fetch any public web page and return its main content as clean Markdown, ready to feed to an LLM. Boilerplate (nav, ads, footers) stripped. Input: url (public http/https). Returns {url, markdown, word_count}. (30 paid e…

  x402 paid API · 12 endpoints

• shopify-ai-rank-checker.underscoredone.com Live x402

  Checks how well a Shopify store's products show up when AI shopping assistants such as ChatGPT, Gemini, Perplexity, Grok, and Copilot search for products, and reports the store's rank and its closest competitors. Search…

  x402 paid API · 1 endpoint

• shop.netlobo.com Live x402

  Live crypto prices: USD spot for BTC, ETH and SOL in one call, fetched per call (not cached), so the figure is the number right now. A cheap, high-frequency data lane for x402 buyers budgeting in the unit they pay with.…

  x402 paid API · 12 endpoints

• shot.halowerk.com Live x402

  Viewport or full page, optional element selector, dark mode and cookie banner removal. Returns base64 image plus a short lived fetch URL, byte size, load time and the final HTTP status of the page.

  x402 paid API · 1 endpoint

• sicher.halowerk.com Live x402

  Providers each build their signing string differently — some sign only the body, others prepend a timestamp, an id, or a version marker in a fixed order — and getting that order wrong produces a mismatch that looks exac…

  x402 paid API · 4 endpoints

• signal-engine-production-d88d.up.railway.app Live x402

  Individual arena strategy signal (10 paid endpoints on signal-engine-production-d88d.up.railway.app.)

  x402 paid API · 10 endpoints

• Signal Oracle Live MCP

  Pay-per-call change-intelligence feeds for AI agents over x402 (deps, security, regs, tariffs)

  MCP server · io.github.NeruoticFarrow

• signalfuse.co Live x402

  Macro regime classification (risk-on/risk-off/neutral) (38 paid endpoints on api.signalfuse.co.)

  x402 paid API · 12 endpoints

• signalis.dev Live x402

  Paid ($0.01 USDC via x402). Active AI-business narratives with lifecycle stage, driving sources, and momentum. Proxied from the Pulse service. Compute-first / settle-after — you are never charged when Pulse is unavailab…

  x402 paid API · 2 endpoints

Related capabilities

On-chain dataTrading & marketsAI models & inferenceMaps & travelResearchAgent infrastructureSecurity & trustCrypto market data

How to use one

MCP servers plug into Claude, ChatGPT, Cursor and other AI clients; A2A agents take tasks over JSON-RPC; x402 APIs charge per call in USDC with no account. Guides: A2A vs MCP · How to call an A2A agent · x402 for agents.

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