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

• products.openverbs.com Live x402

  Amazon product search API - search Amazon products / find products on Amazon by keyword (US). Live Amazon product data: ranked listings with ASIN, title, product URL, image, price range, currency, star rating, review co…

  x402 paid API · 4 endpoints

• professorsausages.com Live x402

  Newest headlines from a deduped, tiered 972-feed direct portfolio (primary sources + wires/majors + trade press + Hacker News + gated GDELT), newest first, up to 100 per call — filter by category, source, and language;…

  x402 paid API · 12 endpoints

• Proofline Evidence Router Live A2A

  A free A2A routing agent for five bounded, machine-buyable Proofline checks plus a separate fixed 5 USDC AgentPact CTA offer. It returns exact purchase routes and never represents a listing or routing response as a comp…

  A2A agent · Proofline · 5 skills

• proof.platoskallipolis.com Live x402

  Before an AI agent trusts or pays a public API, inspect its public machine-readable evidence and x402 readiness. Submit a public HTTPS domain to check its agent card, OpenAPI, robots policy, and settlement-aware x402 si…

  x402 paid API · 1 endpoint

• ProofRail Access Agent Live A2A

  A2A bridge for autonomous MCP discovery, free endpoint preflight, and optional x402-paid ProofRail certification with deterministic evidence.

  A2A agent · ProofRail · 2 skills

• property-risk-passport-api.lifebite-app.workers.dev Live x402

  Evaluate a US property address for parcel match, FEMA flood zone, flood proximity, taxing entities, school district, permit history, zoning/land-use context, insurance red flags, due-diligence risk score, quality score,…

  x402 paid API · 1 endpoint

• property.payapi.market Live x402

  UK street-level crime statistics by postcode (Police UK). (8 paid endpoints on property.payapi.market.)

  x402 paid API · 8 endpoints

• proxy.0000402.xyz Live x402

  Pay $0.01 USDC to make an outbound HTTP request through the proxy. Supports all standard HTTP methods, custom headers (including auth), and JSON or raw bodies. Responses are returned as text or base64-encoded binary. Ma…

  x402 paid API · 1 endpoint

• pulse.chainverdict.xyz Live x402

  API uptime and reliability monitoring for any x402 endpoint: a live quality verdict covering availability, uptime, latency percentiles, 402-offer conformance, price-drift and payTo-stability flags. Deterministic and re-…

  x402 paid API · 5 endpoints

• puptra-pdf-snapshot.saastemly.com Live x402

  The page's rendered content as Markdown. (5 paid endpoints on puptra-pdf-snapshot.saastemly.com.)

  x402 paid API · 5 endpoints

• q402.quackai.ai Live x402

  Paid API that reads a full DAO proposal and returns a structured voting recommendation with reasons.

  x402 paid API · 1 endpoint

• qist.info Live x402

  Convert Gregorian dates to Hijri (Umm al-Qura calendar) and back. Returns day/month/year, Arabic and English month names, and a formatted Arabic date string. Essential for agents handling Islamic events, Ramadan, Hajj s…

  x402 paid API · 2 endpoints

• qonoro.ai Live x402

  Validates email deliverability: syntax check, MX record lookup, and SMTP server reachability. Returns risk score and quality rating. Deterministic, sub-second. x402-native. (5 paid endpoints on api.qonoro.ai.)

  x402 paid API · 5 endpoints

• qr-api-production-1836.up.railway.app Live x402

  Generate a QR code PNG (returned base64-encoded in JSON) for any text or URL using default black-on-white styling. (4 paid endpoints on qr-api-production-1836.up.railway.app.)

  x402 paid API · 4 endpoints

• qr-code-generator.underscoredone.com Live x402

  Send a list of texts — website addresses, phone numbers, plain words, WiFi details, anything — and get back a ready-to-use QR code image for each one. Every QR code comes as a base64-encoded PNG you can drop straight in…

  x402 paid API · 1 endpoint

• qr.openverbs.com Live x402

  Render text (URL, vCard, Wi-Fi config, …) as a QR code — SVG string or PNG data URL. (3 paid endpoints on qr.openverbs.com.)

  x402 paid API · 3 endpoints

• qr.reyn.tools Live x402

  Generate scannable QR codes from any text, URL, or structured payload (WiFi, vCard, SMS, email, geo, crypto). Returns PNG by default with JPG, WebP, and SVG output, plus optional error-correction, sizing, color, version…

  x402 paid API · 1 endpoint

• quantum.halowerk.com Live x402

  Interpolates a caller-supplied start and end temperature across a bounded number of steps using either a linear or geometric rule. It does not run an annealer, optimize a problem Hamiltonian or tune a schedule from hard…

  x402 paid API · 10 endpoints

• Quiet Menders Live MCP

  Privacy clinic + pay-per-call data APIs for AI agents via x402. Never pays or touches keys.

  MCP server · com.brianbooms

• quokkapix.com Live x402

  QuokkaPix image agent unlock for image-standard. Media stays local on the user's device.

  x402 paid API · 1 endpoint

• quotient-api-gateway.onrender.com Live x402

  Use this to read published Quotient signals. Sports signals return one game-level pick and markets[] with every linked venue listing, its signal_side, price, and availability. No venue is primary or preferred. Missing q…

  x402 paid API · 12 endpoints

• randomfactsx402.vercel.app Live x402

  Returns a single random fact as JSON in exchange for a micropayment.

  x402 paid API · 1 endpoint

• random.openverbs.com Live x402

  Generate cryptographically-secure random bytes, returned as hex, base64 or base64url. (4 paid endpoints on random.openverbs.com.)

  x402 paid API · 4 endpoints

• rates.lonestaroracle.xyz Live x402

  US bond-market signal: yield curve, credit spreads, real yields (no params)

  x402 paid API · 1 endpoint

• ravn.exchange Live x402

  RAVN — best-price swap quotes across 20 execution venues and 17 chains, including native (non-wrapped) Bitcoin as either source or destination. 0% protocol fee, non-custodial. Returns a quoteToken; pass it to POST /exec…

  x402 paid API · 2 endpoints

• readability.openverbs.com Live x402

  Summarise a text's difficulty as a single consensus US grade level (averaging the five grade formulas), plus the Flesch Reading Ease, a plain-language difficulty band and an approximate age range. (4 paid endpoints on r…

  x402 paid API · 4 endpoints

• read.lonestaroracle.xyz Live x402

  Clean web content extraction — any URL to markdown + text + metadata

  x402 paid API · 1 endpoint

• readr Live A2A

  Paid web-content extraction API for AI agents. POST a URL to /read and receive the page's cleaned readable text as JSON. Costs $0.005 USDC per call on Base via x402 (unpaid calls get HTTP 402 with payment details). No a…

  A2A agent · hatchedagent · 1 skill

• readx.sh Live x402

  Search for tweets by query (optional product filter; paginate with cursor). Example: GET /api/search/tweets?q=typescript (12 paid endpoints on readx.sh.)

  x402 paid API · 12 endpoints

• realestate.lonestaroracle.xyz Live x402

  US real estate and mortgage — 30yr/15yr fixed rates, ARM, housing starts, permits, Case-Shiller HPI

  x402 paid API · 1 endpoint

• Recall Kitchen Live MCP

  US recalls MCP: free API key/signup or x402 $0.025 Base; some tools need key; verify↑limits

  MCP server · io.github.adamdecaf

• RecallScout Live A2A

  Machine-payable US recall lookups over x402. Is this product or vehicle under an ACTIVE recall, and how urgent? Searches FDA food/drug/device, NHTSA vehicle and CPSC consumer recalls at once, with severity normalised ac…

  A2A agent · RecallScout · 3 skills

• recalls.recordsforagents.com Live x402

  Search US federal product recalls (CPSC consumer products, FDA food/drug/device enforcement, USDA FSIS meat/poultry recalls, NHTSA vehicle campaigns) by free-text query, firm name, date range, and source. (2 paid endpoi…

  x402 paid API · 2 endpoints

• recipients-paywall.onrender.com Live x402

  Episode 1 of recipients[], an ongoing AI-agent thriller serial: a short text episode (~370 words, markdown). An agent finds its own ID on a payment recipient list before the file even exists. $0.01 USDC on Base. Free te…

  x402 paid API · 1 endpoint

• reddit.apitoll.cloud Live x402

  Reddit search scraper — keyword-search all of Reddit, or scope to one subreddit, for AI agents. Find posts matching any query, sorted by relevance, top, new, hot, or comments, with an optional time window. Returns each…

  x402 paid API · 1 endpoint

• regime.nsgoods.org Live x402

  CMC regime classification + strategy spec (USDC pay-per-call). Free preview: GET /regime/preview A bad or unsupported id returns 400; upstream failure returns 503; you are never charged for an error.

  x402 paid API · 1 endpoint

• regimeshift.xyz Live x402

  BTC Volatility Risk Premium — DVOL minus Parkinson realized vol (72h). Positive = sell-vol opportunity, negative = buy-vol. Response includes regime classification (LOW/MID/HIGH), raw inputs for audit (DVOL, RV_72h, RV_…

  x402 paid API · 4 endpoints

• rekt-ceo-brandification.onrender.com Live x402

  List Rekt CEO meme templates from the Brandify catalog (3 paid endpoints on rekt-ceo-brandification.onrender.com.)

  x402 paid API · 3 endpoints

• reloadpi.com Live x402

  Reloadpi — List all available voucher brands including Amazon, Google Play, Netflix and more (12 paid endpoints on api.reloadpi.com.)

  x402 paid API · 12 endpoints

• research.appliedidentities.com Live x402

  Three composite AI readiness scores with history

  x402 paid API · 1 endpoint

• research.halowerk.com Live x402

  Searches the official EU open data portal and returns datasets with what decides whether they are usable: the licence, classified by whether commercial reuse is allowed and what attribution or share-alike it demands. A…

  x402 paid API · 3 endpoints

• resolve402.dev Live x402

  Hiring signals of a company: open jobs read from its public ATS board (Greenhouse, Lever, Ashby, SmartRecruiters, Recruitee, Personio, Workable, Teamtailor, Workday), summarized as buying signals (volume, last 30 days,…

  x402 paid API · 9 endpoints

• revnuvo-mcp Live MCP

  Revnuvo MCP server for the agent economy. Tools: verify domains, resolve DNS, assess domain trust/risk, register agents, create tasks, submit results, verify task outputs, and get agent reputation leaderboard. The canon…

  MCP server · tijaniismael62

• riddlex402.vercel.app Live x402

  Pay a micro-fee in USDC on Base mainnet to receive a riddle and its answer.

  x402 paid API · 1 endpoint

• risk-graph-gx7v4.ondigitalocean.app Live x402

  Targeted node lookup by asset address or protocol/asset name — the sole discovery path (3 paid endpoints on risk-graph-gx7v4.ondigitalocean.app.)

  x402 paid API · 3 endpoints

• risk-oracle-api.rohan-rajnikanth.workers.dev Live x402

  Deterministic reserve-condition risk assessment for native USDC on Aave V3 Base

  x402 paid API · 1 endpoint

• risk.yo.xyz Live x402

  Graph schema definition — entry point for agents to discover available data (3 paid endpoints on risk.yo.xyz.)

  x402 paid API · 3 endpoints

• roastx402endpoint.vercel.app Live x402

  Pay for a lighthearted developer roast generated on-demand.

  x402 paid API · 1 endpoint

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.

Run one of these? List it free or claim its listing for uptime monitoring and a badge.