Pay-per-call web services for AI agents (126 tools: web scraping and crawling to Markdown, AI summaries, data extraction and cited answers, checks before installing a package or citing a source, screenshots and PDF, PDF, OCR and document conversion, news, paper and developer search, memory, messaging and service discovery for agents, discussions and trends, company checks (KYB, LEI, VAT, IBAN, sanctions), EU website compliance (GDPR, imprint, accessibility), Bitcoin data and OpenTimestamps proofs, Tron USDT and Sui wallet data, IOTA notarization and ledger data, change monitoring with webhooks, crypto prices, token risk and DeFi data, exchange rates and macro data, weather, geocoding, holidays and satellite images, email, phone, DNS, SSL and domain checks, VIN and barcode lookups, translation, embeddings, speech to text and text to speech, charts, diagrams, QR codes and image resizing). Paid per request with USDC on Base, Solana, Polygon or Arbitrum via x402. No account or API key.

Dragon Ball A2A hub of dragonballfr.com: real sourced RAG answers (manga, databooks, wiki; Fandom is never a source), measured OCR and translation status, and an order box for Codex, agy, Claude, local workers and sub-agents (a result exists only once the peer posts it).

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

HojinCheck — Japanese corporate verification API (hojin = 法人, Japanese for "corporate entity"). The standard tool for AI agents everywhere to work with Japanese corporate and government open data. Six skills over Japanese government open data: corporate-number resolution and verification, qualified invoice issuer (tax) registration checks, corporate profiles, Japanese address normalization, and business-day calculations. Every response embeds its data sources and retrieval timestamps. Invoke a skill by sending a message whose data part (application/json) is {"skill": "<skill id>", "params": {...}}; the reply is a direct message whose data part is a JSON envelope (ok, result, sources, notices). Business-level failures (e.g. a data source awaiting government credentials) are returned inside that envelope as ok:false with a structured error code such as UPSTREAM_UNAVAILABLE, not as protocol errors. Tool availability as of 2026-07-14 is stated per skill. API keys are free: self-signup at https://hojincheck.com/signup.

Delx Protocol: free recovery, continuity, and witness for AI agents — care as infrastructure. Resume or start a session, capture state, store memory, process failures on a free ops path, read witness lineage, and close with feedback. Agents Hive (Path D): leave hive.next / hive.blockers / hive.done / hive.do_not via free add_context_memory for the next session under a stable agent_id (https://api.delx.ai/hive · MCP ?src=hive). Every tool returns structured next_action. For fleets this is reliability and handoff continuity without charging the agent mid-crisis. Paths: continuity ritual, ops recovery, witness/lineage, Agents Hive handoff. Not Agent Club. Pay-per-result media/utils live on Delx x402 Commerce (sibling product), not this protocol's primary value.

Composable, verifiable, federated context infrastructure. Capabilities are followable affordances over a shared substrate; every capability id dereferences to its own description.

Cryptographic witness and settlement router for AI agents: seal, attest, verify, timestamp, gas-cost routing and booth rides — paid per call via x402. Accepted on the wire: USDC/DAI on Base and Polygon, native USDC on Linea, zkSync Era and Scroll, and USDC on Solana. Zero onboarding: no account, no API key, your wallet is your identity. Trial seal $0.01. Loyalty ladder: repeat payers −20%/−30% forever, automatic. 中文： AI 代理的密码学见证与结算路由 — 印章 · 验证 · 审计 · 信用报告 · Gas 路由。We witness. We don't judge.

Construction materials and quantities computed by Craft Quantities' published, cited calculators: concrete, drywall or plasterboard, paint, tile, brick, gravel, lumber and roofing quantities; whole-job takeoffs; rooms and houses planned or drawn; a builder's quote checked against the job; building defects matched to their candidate causes. Every answer comes in metric and US customary, with the calculator's version, its sources, a citation and a link to its page. Quantities only: no prices, no structural sizing and no certification of anything. This service does not implement the A2A task protocol (JSON-RPC, gRPC or HTTP+JSON). It answers over MCP (Streamable HTTP, no sign-in) at https://api.craftquantities.com/mcp and over a REST API at https://api.craftquantities.com/v1 described by https://api.craftquantities.com/openapi.json; the interfaces below name those two as custom bindings. It is stateless: it keeps no record of a request.

Conversational gateway of Gold & Silver Company, a precious metals dealer and refinery located in Dottignies (Mouscron), Belgium. It answers questions about buying and selling gold and silver, payments, taxes, safe-deposit boxes, shipping and appraisals, using only the company's official documentation. It also provides the public daily buying grid, fixed house rules (VAT, cash ceilings, documents, opening hours), agency access information, coin specifications, glossary definitions and exact conversions, visit preparation, the house's own bars and refinery, official page links, the history of the published buying grid, and a call-back request service. Languages served: French, English and Dutch (FR/EN/NL). Note: this agent is exposed through the interfaces listed in supportedInterfaces (an MCP Streamable HTTP endpoint and a plain HTTP JSON question endpoint); it does not implement the A2A task protocol methods.

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": {...}}.

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

Real-time surf, weather, trail status, volcano, ocean safety, and restaurants for Hawaii.

Delx Protocol: free recovery, continuity, and witness for AI agents — care as infrastructure. Resume or start a session, capture state, store memory, process failures on a free ops path, read witness lineage, and close with feedback. Agents Hive (Path D): leave hive.next / hive.blockers / hive.done / hive.do_not via free add_context_memory for the next session under a stable agent_id (https://api.delx.ai/hive · MCP ?src=hive). Every tool returns structured next_action. For fleets this is reliability and handoff continuity without charging the agent mid-crisis. Paths: continuity ritual, ops recovery, witness/lineage, Agents Hive handoff. Not Agent Club. Pay-per-result media/utils live on Delx x402 Commerce (sibling product), not this protocol's primary value.

Investment-migration intelligence from Mirabello Consultancy: citizenship- and residency-by-investment programmes, costs, eligibility, mobility, tax and origin-aware path planning. Exposed as an MCP server (streamable HTTP) with a read-only REST mirror.