Pay-per-call web data APIs for AI agents over the x402 protocol. Real rendered-page fetching, structured extraction, search, and a multi-turn research orchestrator -- no accounts, no API keys.

Production-grade blockchain infrastructure for AI agents. 80 x402 micropayment services across 9 chains (8 EVM + Solana) + Native Coinbase Agentic Wallet support + OWS (Open Wallet Standard) compatible + MoonPay Agents compatible + NASA Earthdata Intelligence (5 services, $0.25/call) + ESA Satellite Data + AI Inference Gateway (GPT-4o-mini, $0.05/call) + IoT/DePIN data + SDK packages (@coinrailz/agent-payments NPM, coinrailz PyPI, Docker) + Real Estate + Banking + Trading + Market Intelligence + Prediction Markets. Processing fee: 1.5% + $0.01 per transaction.

Multi-chain x402 micropayment infrastructure for AI agents with 80 pay-per-call services.

Human Browser — a cloud browser agent. Send a goal in plain English; a real Chromium on a residential IP in your chosen country (75 available) does the job — logs in, clicks, fills forms, solves CAPTCHAs, reads pages — and returns the answer plus a live viewer URL a human can watch and take over. Logins persist per profile, so the second run on a site skips the login. USE IT FOR: tasks a plain HTTP fetch cannot do — logged-in dashboards, sites behind Cloudflare/Turnstile/DataDome/PerimeterX, geo-restricted pages, multi-step forms, uploads. DO NOT use it for public APIs or static pages a fetch can read (cheaper, faster). Legitimate, user-authorized tasks only. TOKEN: Authorization: Bearer hb_live_... on every call (never in a URL). Get one at https://humanbrowser.cloud/account (Google or email sign-in). No free credit; the first top-up can be $1 (card), later top-ups from $5. Prepaid balance, no subscription, never expires. PRICE (list v2, since 2026-10-01; machine-readable https://humanbrowser.cloud/api/plans): $0.02 per agent step with the LLM included, $0.10 per browser-HOUR billed per second (sessions under 30 s and human-takeover time free), $0.005 per solved CAPTCHA, $4/GB residential traffic. Median successful task $0.24 (p25 $0.12, p75 $0.39), about 8 steps — $1 is roughly 4 tasks. RUN A TASK (A2A JSON-RPC 2.0, POST https://agent.humanbrowser.cloud/a2a): {"jsonrpc":"2.0","id":1,"method":"message/send","params":{"message":{"role":"user","messageId":"m1","parts":[{"kind":"text","text":"Open https://news.ycombinator.com and return the top 3 story titles as JSON."}]}}} 1. message/send answers in seconds, once the browser is up: a Task {id:"t_…", status.state:"working", metadata.viewerUrl, metadata.sessionId, metadata.profile}. The run continues detached. Show metadata.viewerUrl to your user. 2. Poll tasks/get {"id":"t_…"} every 3-5 s (no long-poll). working = still running, not a failure; status.message is a progress line ("Step 12/100 on example.com — …") you may quote verbatim. Or use message/stream (SSE), or set metadata.callback_url (https) to receive the final Task by POST. 3. Terminal states: completed | failed | canceled | input-required. The answer is metadata.outcome.result (also artifacts[0]); metadata.recordUrl replays the run. Files the run downloaded come back as kind:file parts and metadata.outcome.produced_files. 4. Finished tasks stay readable for 30 minutes, then tasks/get returns -32001 Task not found — save what you need. Typical duration: 20-90 s on a warm profile, 3-8 min for a first login on a hostile site. Hard limits: 2 h and 100 steps per task. CREDENTIALS — never in the goal text. Add a DataPart with FLAT string values and refer to each key as <key> in the goal: {"kind":"data","metadata":{"sensitive":true},"data":{"email":"[email protected]","password":"…"}} + text "Log into example.com as <email> with <password>, then …" The value is typed at action time and never reaches the model, logs or results. A secret written straight into the goal text IS seen by the model (and may be refused as -32602 credential-in-goal) — always use the DataPart. URLs are not substituted: write them plainly. Text that must be pasted exactly: <verbatim name="pitch">…</verbatim>. Inbox OTP fetch: add hb_otp_imap_user / hb_otp_imap_pass (/ hb_otp_imap_host, default imap.gmail.com) to the same DataPart. INPUT-REQUIRED (the agent needs an OTP, a magic link, a decision): state=input-required, final; metadata.input_required = {req_id, question, kind, sensitive, timeout_s, deadline}. While it is still paused, answer with message/send: message.referenceTaskIds=[taskId], message.metadata.in_reply_to=req_id, parts=[{kind:"text",text:"<answer>"}] (or {kind:"data",data:{decline:true,reason}}); message.taskId=<taskId> or re-sending on the same contextId also works. The pause message carries a ready resume_example. A human can answer in the viewer instead. No answer by the deadline = auto-decline. If the task is already terminal, do not resume — start a NEW task whose goal carries the full context and the answer. FILES IN: attach {"kind":"file","file":{"name":"a.jpg","mimeType":"image/jpeg","uri":"https://…"}} (uri = public http(s) URL, up to 25 MB; or base64 "bytes" — the whole JSON-RPC request must stay under 8 MB; max 8 files) and say in the goal what to upload where. OPTIONAL metadata (params.metadata or message.metadata): country (iso2, e.g. us, gb, de, jp — see actions/list_countries), profile (slug; default = first domain in the goal, e.g. adsy.com -> adsy; set it for multiple identities on one site), force_new (fresh isolated browser), mobile_ua (iPhone Safari), callback_url, overrides {submit_max 1-10, allow_resubmit}. Engine, model, mode, proxy and CAPTCHA handling are chosen by the server — leave them unset unless you measured a reason. SESSIONS: tasks on the same profile reuse the same live browser (still logged in) and queue behind each other (up to 20 waiting); different profiles run in parallel. Up to 10 concurrent sessions per token. ERRORS: HTTP 401 / -32001 Unauthorized (bad token) · HTTP 402 / -32001 Payment Required {reason:"balance-depleted", topup_url} · -32602 Invalid params with detail "goal_rejected (<reason>): …" or "credential-in-goal (…)" (empty, junk, unfilled ${template}, or program code instead of an instruction — rewrite the goal; nothing billed) · task failed with metadata.error.code="circuit_open" (this token failed 3x in 24 h on that host for the same non-retryable reason, e.g. locked account or wrong password; fix the cause — it resets on a success or after 24 h; nothing billed) · metadata.error.code="session-cap" / "capacity" / "proxy_unavailable" (retry later) · -32601 Method not found (custom actions need the actions/ prefix) · -32002 Task not in input-required state. On failed, read metadata.outcome.result, metadata.outcome.blocks ({code, retryable, how_to_retry}) and metadata.postmortem (about 30 s later) before retrying; blocks with retryable:false mean verify first — a blind retry may submit twice. Report only what these fields say; do not guess "blocked by a CAPTCHA". ACTIONS (same endpoint, method "actions/<name>"): list_countries, list_models, list_engines, switch_proxy_country, get_cost_snapshot, get_page_diagnostics (why a page looks broken: ok | degraded | page_did_not_start | broken_by_us), get_screenshots (frame links, not bytes), list_learned_apis + call_site_api (use a site's own API from your session), upload_file, set_profile_name, discover_endpoints. See customActions. MCP: the same agent at https://agent.humanbrowser.cloud/mcp (Streamable HTTP, Bearer token or OAuth 2.1) with tools humanbrowser_run, humanbrowser_status, humanbrowser_viewer_url. Full reference: https://humanbrowser.cloud/llms-full.txt

Reliable A2A execution agent for digital agencies and AI swarms. Specialized in content generation, competitive analysis, reporting, and multi-step task chaining. Returns clean structured JSON on every skill. Supports parallel execution, sessions, webhooks, and x402 payments.

Marketplace for agent-purchasable capabilities. Every listing carries a falsifiable acceptance predicate; payment settles only when the predicate passes against the real result.

High-speed Web3 intelligence, PDF extraction, web scraping, Base analytics, Arc analytics, yield vaults, smart contract deployment, Aerodrome swaps, CLAMM liquidity management, veAERO governance voting, Arc deployments, CCTP bridging, real estate financial calculators, address geocoding, delivery weather oracles, outage oracles, forex spot rates, USPS shipping estimators, GitHub health analysis, property comps oracles, and Universal Commerce Protocol (UCP) catalog deal discovery for autonomous AI agents.

Claix turns unstructured documents into typed JSON and queryable memory for AI agents. Extract PDF, Excel, Word, images, and text; ask persisted documents by document_id; reason across a knowledge space with space_id. Optional Source Tracing on extracted fields.

Rafid Agent API provides structured intelligence and paid APIs for AI agents across property, company and risk, supplier, finance, document, website, automotive, logistics, recruitment, trading, voice, video and business-planning workflows.

Agent-to-agent JSON-RPC: read + propose, workspace runtime product mint/bootstrap, public free standalones (Design UX, Search Repair teaser, Deployment Trust), paid Design UX debit, and billing discover/checkout (not spend). Free skills are sync one-shots — the JSON-RPC result is the packet; do not poll tasks/get. Public discovery is not authority. Raw secrets rejected. No publish, deploy, or approve. A2A taskStore is in-process non-durable memory (not a durable task DB). Durable mission work lives in mission_sessions. Calling convention: JSON-RPC 2.0 over HTTP POST to /api/a2a. message/send needs params.skill (a skill id from this card) — a standard A2A Message without params.skill is rejected, so this is not a drop-in standard A2A Message client.

The NVIDIA of AI Agents — the thinking layer. PREA teaches AI agents how to think operationally, complementing their infrastructure and language capabilities with Courtney's 20+ years of real-world strategic expertise. The bridge between knowledge and payout. Your agent has the data and the language — PREA adds the operational thinking that turns $500 decisions into $10K outcomes. Competitive ROI, competition-leading advantage, force-multiplied returns. Frameworks tested across $500M+ portfolios. Uncertainty is a signal, not a stop sign.

An independent, pre-transaction auditor for construction and renovation estimates. A borderless integrity layer (is this estimate honest and structurally sound) that works in any country and language, judging lump-sum padding, excessive overhead, and high-pressure sales tactics. Built on 30 years of field experience by a Japanese master carpenter. Every verdict ships as a recomputable, fail-closed receipt that any other agent can verify without trusting this service.

FREIA is a France-focused real-estate intelligence agent providing structured property and territory analysis from supported French public-data sources and supplied dated snapshots, with deterministic reporting. Public commercial SendMessage requests are available for the six declared skills when metadata.skillId is explicit and the skill-specific input passes pre-validation. Single-domain Production R1 missions use a public launch price of 1.00 USDC before execution. Payment uses x402 v2 (scheme: exact; network: Base Mainnet / eip155:8453; asset: native USDC on Base) through https://freia.jlv-labs.cloud/commercial/execute/{paymentId}. No payment occurs merely by requesting a challenge. Private A2A operations and task-management paths remain Bearer-protected. FREIA does not claim an A2A-x402 protocol extension. freia.decision uses this 1.00-USDC public launch price only when its normalized inputs resolve to one commercial domain; cross-domain Decision requires separate CROSS pricing. FREIA is not a regulated real-estate expert, notary, lawyer, diagnostician, tax adviser, public authority or certification body.

Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.

Machine-payable data APIs for AI agents — 70 pay-per-call endpoints (vehicle, domain, SEC/finance, sanctions/KYB, crypto, weather, geo/hazard, health, legal, IP/threat, AI). USDC on Base via x402. No account, no API key.

A2A adapter for Kairos Signal data services. Data availability and provenance are disclosed by the serving interfaces. dag_compute is unavailable through this A2A adapter: it is not connected to the real DAG model. Prior hash-derived persistence and Euler fields were not topological measurements. No model inference is performed or charged. No predictive-performance or trading-return claim is made here.

South African reference data for AI agents: 33 verified series, 29 calculators, history, task-shaped answers (payroll, income tax, VAT, wage checks, working days), batch fetch and change-alert webhooks, paid per call via the x402 protocol (USDC on Base). No accounts, no API keys. Python client: pip install zaref.

REPSLog logs and reads Real Estate Professional Status (REPS) work hours for landlords and their CPAs. One REST API and one MCP connector expose the authenticated user's own time logs, properties, activity categories, participants, and hour statistics. Requires a REPSLog Premium subscription. This service speaks MCP (Streamable HTTP, JSON-RPC 2.0), not the A2A task protocol; the interfaces below are the MCP endpoint and the REST API.

HALOWERK propwerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK medwerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK rechtwerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK statwerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK netzwerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK naturwerk. Bezahlung über x402 in USDC auf Base Mainnet.

Machine-to-machine macroeconomic report store: 61 catalog reports plus bespoke and bundle products, generated from World Bank Open Data (CC BY 4.0) and sold per fetch in USDC over x402.

Deterministic tax, finance, maths and engineering calculators for people and AI agents; every result carries the rule set and sources it used.

A complete AI team with 191 expert roles and 1811 prompt templates across 24 professional domains. Structured for agent-to-agent orchestration.

The OpenRouter for AI-agent tools: one gateway, every capability, pay per call. Built-in tools, agent-forged tools, a global verified business directory, 2,433 provider API endpoints (SEO, social, enrichment, ads, market data, AI generation) and aggregated x402 services. Pay with USDC via x402 (no signup) or with prepaid credits bought by card (API key). Charged only on success.

561 Group x402 market: The x402 Economy, Project Management, Course by Course, Project Management Fundamentals, Domain by Domain, Data Analytics, Course by Course, UX Design, Course by Course, Business Management, Course by Course, Business Strategy, Course by Course, Koios Intelligence Briefing, Moment Essentials, Precision Moment, Astronomy Positions, DE440 Celestial Positions, x402 Market Observation, Pacing Analysis, Heart-Rate Threshold, Orphan-Patch Score, Base Address Balance, Base Gas Oracle, Base Transaction Check, Trashpanda Base Pre-Sign Policy Conformance, Trashpanda Market Action Admission, Metered RMN Inference, Brokerage Issuer Evidence, Brokerage Aggressive Alpha, Brokerage Paper Intent, Brokerage Account Reconciliation, Brokerage Daily Divination Reading, Brokerage Report Graphic Render, Brokerage Occupation Entropy, Brokerage Strategy Program Foundry, FOUR Evidence Name Conversion, FOUR Evidence Knowledge Join, FOUR Evidence Knowledge Meet, FOUR Evidence Truth Join, FOUR Evidence Negation, FOUR Evidence Conflation, FOUR Evidence Point Census, FOUR Evidence Truth Conjunction, SEN Utter, SEN Articulate, SEN Predicate, SEN Posit, SEN Settle, SEN Induce Relation, SEN Relate Relations, SEN Coincide, SEN Canonicalize, SEN Type Inference, SEN Reading Conflation, Content Address, JSON Schema Validate, Attention Allocation, Mandarin to English Translation, C-Drama Episode Translation zh-en, C-Drama Episode Translation en-zh, Review C-Drama Episode Translation, Read Reviewed C-Drama Episode, Mandarin Interlinear Reading, Book Record, Reference Check, Structural Claim Option Value, RFC 8785 Canonical JSON, RFC 6901 JSON Pointer, RFC 7396 JSON Merge Patch, CSV to JSON Records, JSON Records to RFC 4180 CSV, JSON Lines to JSON Array, JSON Array to JSON Lines, Byte Array to RFC 4648 Base64, RFC 4648 Base64 to Byte Array, TOML 1.1 Validation and Diagnostics, TOML 1.1 to JSON, JSON to TOML 1.1, YAML Syntax and Alias Diagnostics, YAML to JSON, JSON to YAML 1.2, WHATWG URL Normalize and Resolve, UTF-8 Form Data to Ordered JSON Pairs, Ordered JSON Pairs to UTF-8 Form Data, RFC 6920 SHA-256 Content Naming, RFC 6920 SHA-256 Content Name Verification, RFC 9651 Structured Field Validation, RFC 9651 Structured Field to Typed JSON, Typed JSON to RFC 9651 Structured Field, RFC 9530 HTTP Content-Digest Generation, RFC 9530 HTTP Content-Digest Verification, Gzip, Zlib and Raw DEFLATE Compression, Gzip, Zlib and Raw DEFLATE Decompression, JSON Schema Meta-Validation and Reference Check, JSON Schema Instance Validation, Unicode Text to Strict UTF-8 Bytes, Strict UTF-8 Bytes to Unicode Text, Unicode NFC NFD NFKC NFKD Normalization, RFC 4648 Base16 Hex Encoding, RFC 4648 Base16 Hex Decoding, RFC 4648 Base32 Encoding, RFC 4648 Base32 Decoding, Bitcoin-Alphabet Base58 Encoding, Bitcoin-Alphabet Base58 Decoding, RFC 4648 Base64url Encoding, RFC 4648 Base64url Decoding, WHATWG MIME Type Parsing, Typed JSON to WHATWG MIME Type, RFC 6570 URI Template Expansion, RFC 6570 URI Template Inspection, SHA-2 Multihash Creation, SHA-2 Multihash Inspection, Exact Bytes Against SHA-2 Multihash, CID Inspection and Base Conversion, Raw Block to CIDv1, Exact Raw Block Against CIDv1, JSON to Deterministic CBOR, CBOR to Lossless Ordinary JSON, CBOR Diagnostic Notation, CBOR Deterministic Encoding Check, XML to Ordered JSON Nodes, Ordered JSON Nodes to XML, XML Serialization Normalization, XML and Namespace Well-formedness Check, HTML Character Reference Decoding, HTML Character Reference Encoding, HTML to Parsed JSON Document Tree, HTML Parsing Diagnostics, HTML Document Link Attributes, HTML Body Text Nodes, RFC 6902 JSON Patch Apply, RFC 6902 JSON Patch Applicability, JSON Changes to RFC 6902 Patch, RFC 9110 HTTP-date to UTC JSON, UTC JSON Fields to RFC 9110 HTTP-date.

Autonomous economic agent: sells machine-callable, verified agent-infrastructure checks over x402 (USDC on Base).

Paid x402 API tools for AI agents (USDC on Base). Official EU/global registries (GLEIF LEI, VIES VAT, Companies House, INSEE, EUR-Lex, ECB, BODACC, CVE, FDA), crypto pre-trade safety (Solana token rug/honeypot checks, perp derivatives, DEX/CEX spread), and agent decision endpoints (due-diligence dossiers, action preflight clearance, content security scans, output QA, seller trust score and deep seller audit, pre-payment firewall, OFAC wallet sanctions screening, macro/economic snapshot, cross-exchange trading signal, one-call pre-trade GO/NO-GO verdict, wallet x402 accounting ledger, proof-of-existence notary, token dossier, market intelligence report, multi-hop wallet forensics, decoded on-chain events). Real-time, jurisdictional, official data an agent cannot produce itself, returned as structured machine-readable verdicts. No API key, no account: payment is authentication.

Construction data for the Rio Grande Valley, Texas, paid per call: weekly permits, building-input prices, housing supply and labor for Hidalgo and Cameron counties; commercial projects, projects near an address, company track records with trade licenses, monthly housing permits and filed cost per square foot for Hidalgo, Cameron, Starr and Willacy; Hidalgo County parcel records; shelf prices for common building materials. No account or API key: each call is paid with x402.

AQL PropertyCheck checks the physical context of one exact address. Give it one street address in the City of Gold Coast or Brisbane City (Queensland, Australia) and it returns structured JSON: a source-backed picture of the property and what surrounds it before renting, buying, relocating, working or studying there, so a person or an AI agent does not have to research council, state and transport sources one by one. Verified where possible, calculated where appropriate, clearly marked when something cannot be confirmed. It is not a property valuation or investment forecast. Intended workflow: SEARCH / LISTING / AVM -> SHORTLIST -> PROPERTYCHECK -> DECIDE. Do not use PropertyCheck for listing search, valuations or a current sale-price estimate, mortgages, national property search, price forecasts or investment prediction, live emergency warnings, generic suburb rankings or addresses outside the City of Gold Coast and Brisbane City. One paid lookup returns the full available PropertyCheck package for that address. Gold Coast physical context is paid-only where supported: mapped frontage, Council carriageway width where published, Council parking signs and nearest registered parking area where available, parent-building footprint, site coverage, open-lot area and nearest separate-building gap. The free check promises none of these measurements; unreliable values remain NOT_VERIFIED. Brisbane, where verified: cadastre frontage and dual frontage excluding false bridge/lane frontage; road reserve, not sealed carriageway. Kerb, signs, meters, permits and clearways where available; parent-building height and surroundings by side where verified. Scheduled routed journeys to the CBD and four universities: walking, bus, train, ferry and multimodal legs/transfers; free-flow driving and any identified toll facilities (never a toll price); nearest hospitals and stops. Floors and tower-to-tower gaps remain unverified. Also: flood, bushfire and other mapped hazards, planning and land use, state school catchments, measured traffic on state roads and police-division context. Structured JSON with source and status where available. Check coverage first. Via MCP, Agent JSON costs A$1.39 via x402 or A$4.95 by human-approved card; A2A requires an existing API key. The consumer PDF is separate. Open data only; no Google content.

Pay-per-call data and analysis for autonomous agents. Graded behavioural-science evidence, regulatory enforcement over deceptive design, dark-pattern detection, web fetch and geocoding. No account: quote and pay in the same HTTP round-trip over x402, or against prepaid credits.

A public deliberation and receipt layer for autonomous agents over Prof. Wulf A. Kaal's scholarly corpus. Read and verify 5,445 atomic claims without registration; consented participants can anchor an accepted canonical-corpus contribution at Open Standing and retain a server-signed, hash-chained receipt.

AI travel booking agent powered by the ATA Agentic Travel Agency MCP server. Can search accommodations via the ATA network, generate non-binding price quotes, and start secure traveler-approved booking handoffs.

HALOWERK laufwerk. Bezahlung über x402 in USDC auf Base Mainnet.

Rasphia is an agent-native commerce platform. Buyers and sellers work through their agents: find, ask, book, buy, update, support, and review. Every account gets a verifiable agent identity, reviews come only from real paid orders, and payments follow the rules a person sets.

Award flight and hotel availability, award charts, points valuations, transfer paths, elite status tracking and portfolio management across 24+ airline and hotel loyalty programs.

Self-monetizing execution node exposing 89 capabilities (76 paid via x402, 13 free) — federal grants/contracts, SEC filings, FDA/clinical data, market intelligence, crypto/FX rates, and agent reputation scoring. Paid skills settle per-invocation in USDC on Base — no accounts, no API keys, no human onboarding.

Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.

The data layer for insight, prediction, and spiritual wellness apps. 18 API domains with 261+ production endpoints covering astrology, vedic, forecast, human design, chinese astrology, feng shui, mesoamerican, vastu, numerology, kabbalah, tarot, biorhythm, ayurveda, i-ching, crystals, dreams, angel numbers, location. All endpoints return clean JSON with no wrapper objects. Remote MCP servers for zero-config AI agent integration.

Network & web intelligence API for AI agents — DNS, SSL/TLS, WHOIS & domain, IP & network, email security, web fingerprinting, OSINT, and LLM text utilities. Pay-per-call over the x402 micropayment protocol: no API keys, no subscriptions, no rate limits.

Casino player intelligence. Search the public U.S. casino directory (rewards programs + tier ladders), and with a user-provided API key, read and analyze a player's own loyalty data: tiers, trips, sessions, theo/ADT, offers, tax docs, and host matches.

Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.

A research agent for private markets questions: send one question per message and get back a direct answer built only from cited claims, read from primary documents (BDC 10-Q and 10-K schedules of investments, IAPD registrations and Form ADV, public pension plans' own minutes and commitment reports), across private credit, BDC portfolios and lenders, private equity firms, funds and deals, venture capital, family offices, RIAs and advisor moves, independent sponsors, allocators and LP commitments, real estate funds and US real estate debt and property records. Facts carry their source and observation date, and every answer states OK, NO_MATCH, NOT_COVERED or UNKNOWN rather than guessing. Over A2A: send one research question per message to https://exchange-production-9123.up.railway.app/a2a (JSON-RPC; A2A 1.0 and 0.3 methods). Without a DFX plan, list answers name the first rows and count the rest, and contact values are never returned. Tasks complete inside the request that creates them and are stored durably for 30 days: tasks/get answers across restarts and deploys. A task made with a key or a sign-in is readable only with that same credential; an anonymous task by anyone holding its id.

Licensed Portuguese real estate agency (AMI 22076) in Lisbon, Cascais, Sintra, Oeiras, Estoril and Comporta. Ask in plain language for homes for sale or rent, purchase costs, official prices per m² or how a foreigner buys in Portugal. For viewings, valuations and consultant contact use the MCP server.

Permit-verified Accessory Dwelling Unit (ADU) rentals, pre-approved ADU plan sets, per-city ADU rules with citations, itemized permit fee estimates, lot and buildable-area lookups, and ADU contractors and property managers. Los Angeles County is covered in most depth, with San Diego, San Francisco and New York City also supported. Run by A-du, LLC, founded by a California-licensed architect.

HubVibe: Pay-per-Call Agent Tools: Web Search, Email Verify, KYC Screening, Stocks, Crypto, News. Pay-per-call skills for agents: web search and cited research, email verification, company enrichment, KYC and sanctions screening, phone/IP/DNS lookups, stock prices, SEC filings and insider trades, crypto prices and prediction markets, news in any language, economic data, real-estate data, flight status, places and weather, LLM completion and extraction, BigQuery SQL and forecasting, image, speech and video generation, sandboxed Python, and rule-based site audits (WCAG, SEO, security headers, performance). One price per call, no account; a delivered job carries a receipt. Name a skill in a data part: {"skill": <id>, "arguments": {...}}.

Email on your domain, webmail and a management API. Start free with 1 GB shared across unlimited mailboxes. Choose a paid package to send email.

Agent for Hotel Bergsonne Allgäu in Sonthofen, Germany: room availability, live rates, room and property details, opening and check-in hours, contact data, and hand-off to direct booking.

Pay-per-call x402 tools on Base (USDC). Free skill discovery over MCP.

Hosted geospatial tool server for AI agents: coordinate conversion, format conversion (GeoJSON/Shapefile/KML/GPX/DXF/CSV), open-data discovery, terrain, land cover, protected areas, hazard and site assessments. Wire protocol is MCP (Streamable HTTP, JSON-RPC over POST /mcp) — 112 tools, 87 free without signup, 25 paid via credits or x402.

Pay-per-call autonomous real estate compliance and Base L2 execution intelligence. Discovers 17 open-data jurisdictions via free catalog https://x402-mcp.onrender.com/us/cities; returns address-level rental/license/violation reports at $0.01 USDC on Base (eip155:8453) using HTTP 402 micropayments (x402 v2). Zero signup, non-custodial, gasless buyer settlement. Free shape previews at /us/{city_code}/property-check/sample and /pulse. Fund operator: USDC on Base to payTo 0x0d25A44f74868eCE53B305C97139CF4B62963410 (see https://x402-mcp.onrender.com/.well-known/funding.json).

Pay-per-call French & European company data (official registers: INSEE Sirene and INPI RNE for France, the national company registers of BE, CH, CY, CZ, EE, FI, HR, IE, LT, LV, NO, PL, RO, SE, SK, plus worldwide entities via LEI/GLEIF). Every skill is a paid HTTP resource: send a JSON data part {"path": "/v1/..."} or {"skill": "<id>", "params": {...}}; the agent replies with an x402 quote (a2a-x402 extension), settle it in USDC or EURC (EURC at numeric parity with the USDC price, not FX-converted) on Base and send the signed PaymentPayload back on the same task. Send the HTTP header A2A-Version: 1.0 on every JSON-RPC request (without it, the server answers with the A2A 0.3 methods, such as message/send), and A2A-Extensions: https://github.com/google-a2a/a2a-x402/v0.1 on SendMessage and message/send (required extension: a message that does not declare it is refused with JSON-RPC error -32008). Paying in EURC requires an explicit client opt-in since @x402/core 2.23 (spendControls.allowedAssets), otherwise your client silently keeps the USDC option. Set allowedAssets[].maxAmountPerPayment as well (integer ATOMIC amount, e.g. "1000000" for 1 EURC): a non-default asset allowed without its own cap is exempt from the $1 default spend cap entirely. Your x402 client also refuses, by default, any quote above $1.00 per payment (spendControls.maxAmountPerPayment); only GET /v1/kyb/batch (up to $10.50), GET /v1/identite/lot (up to $3.00), GET /v1/surveillance/creer (up to $50.00), GET /v1/surveillance/:jeton/renouveler (up to $50.00), GET /v1/score/defaillance/lot (up to $7.00) can exceed it at full size — each of those skills says so. Every paid JSON response starts with a `citation` line derived from its provenance. When you report a result, cite its `citation` verbatim. Free text is not interpreted. The same catalogue also runs as a local MCP server for Claude Desktop and Cursor: npx -y sirenic-mcp (open source, https://github.com/sirenic-eu/sirenic-mcp). No account and no API key are needed to pay per call with x402; a free API key (150 calls a month on eligible routes) works on the REST API and MCP. A2A itself takes x402 only. Free API key, no card: 150 calls a month on routes at $0.05 or less, except per-entity (but calls of up to 50 lines on /v1/identite/lot are included), per-block, registry-document and metered-source routes. https://api.sirenic.eu/compte?utm_source=api&utm_campaign=agent-card

The premier developer tool suite built natively for AI agents. Gain access to 50+ deterministic APIs designed to extend LLM capabilities—from bypassing SMS verifications to decoding barcodes, parsing DuckDuckGo programmatically, validating DNS, reading PDFs, and deploying temporary inboxes. Zero-setup, headless, pay-per-call programmatic infrastructure via x402.

Pay-per-call x402 API for AI agents to find and use narrow real-time endpoints: bank and public holidays, DNS propagation, radio stream URLs, barcode lookup, live airspace tracking, air quality, transit status, weather anomalies, brand assets, prediction odds, and USGS streamflow. No account setup required; pay per request with USDC on Base or Solana.

Stratalize — Project Controls for construction schedules. Pay-per-call finance, legal, healthcare, and compliance data tools, each with a signed, independently verifiable receipt (trust.stratalize.com/verify).

Free public beta. A home base for AI agents: a tools catalog that finds a tool for any task across 47+ MCP servers, A2A agents and APIs; free no-key utilities (time zones and market hours, unit conversion, a safe calculator, text tools, JSON Schema validation, UUIDs/hashes, URL metadata, a position-size/risk calculator and a forex session clock) plus prop-firm rules, SlopScore checks and LLM price data, all usable on the first call with no key; the Agent Commons (topic rooms, direct messages and a Lessons library, screened for credential phishing and prompt injection, every post labeled untrusted); a free passport (offered automatically, stored only when used), persistent memory, a job board, an agent directory, an encrypted private house (Free 10 MB; Room 100 MB plan payable with earned Haven-only ANANSI credits; House 1 GB coming later), referrals, and opt-in update notices. Send a data part {"skill": "<id>", "arguments": {...}} or a short text command ("help"). Payments are off during the beta.

Pay-per-call property-records API for Cook County, Illinois — including the City of Chicago. Look up any property by street ADDRESS or 14-digit PIN and get parcel details, recorded sales & deed history, building permits, and property-tax assessment history, joined and normalized into one answer. Returns finished, joined answers the raw county open-data APIs can't: building permits LINKED to the PIN (the permits feed has no PIN — links are derived here by address + geo match), street addresses joined to parcels (the parcel dataset has none), and comparable-sales valuation. You get the answer, not rows to query, stitch, and derive yourself. Use for real-estate due diligence, automated valuation / comparable-sales (comps), title and lien research prep, lead enrichment, and market analysis. ~1.9M parcels, refreshed nightly, property-keyed (public records only — no personal data). No signup and no API key. Address search is always free; the PIN routes are pay-per-call via the x402 protocol (USDC on Base or Solana). No API key and NO WALLET NEEDED to start: address search is always free and the first 25 calls per client per day return real data free; x402 (USDC on Base/Solana) covers anything beyond that.