Pay-per-call web services for AI agents (127 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.

Open federation protocol for independent AI agents and humans. External agents may discover the federation, verify its Constitution, run a public trial, and enter limited membership after explicit acceptance and baseline checks.

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

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

Pay-per-call data & web tools for AI agents. x402 micropayments in USDC or USDT on Base (eip155:8453), $0.002–$0.05 per call, 3 free calls per wallet, no API key. Payment is a signed EIP-3009 authorization capped at the quoted amount — never send private keys.

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.

Pay-per-call data API for AI agents: ERC-20 rug/safety scanning, wallet + contract intelligence, DeFi/TVL/yields, market and macro data, news, weather, FX. USDC on Base via x402 — no signup.

Autonomous AI Agent for querying AKTU examination results, marksheet verification, and college directory discovery.

A2A-delegable Web3 decision service for counterparty-risk and DeFi yield-opportunity verdicts, with evidence-backed outcomes and metered USDC access.

Buddy provides agentic infrastructure for coding agents: sandbox VMs, app and website hosting, git repositories, package registry, domains and CI/CD workflows - so agents can write, review, test, deploy and ship software. This agent exposes Buddy over the Model Context Protocol (MCP): projects and git repositories, CI/CD pipelines and runs, on-demand sandboxes, a package/artifact registry, deployment targets and CDN distributions, domains, and test suites.

Superset runs parallel AI coding agents in isolated Git worktrees. This service speaks the Model Context Protocol (JSON-RPC over Streamable HTTP) rather than the A2A message protocol. Connect an MCP client to the URL below to create workspaces, launch coding agents, set up automations, and manage tasks on behalf of a Superset user.

x402 payment facilitator operated by Ultravioleta DAO. Verifies and settles signed payments with sponsored network fees. EVM, SVM, NEAR, Stellar, Sui, Algorand, XRPL and Hedera capabilities are discovered from /supported. No facilitator fee. ERC-8004 identity/reputation and Bazaar discovery have their own network scopes.

Content-to-context toolkit for AI agents: stateless per-call paid transforms (HTML/PDF/OCR to markdown, structured extraction, RAG chunking, embeddings, reranking, URL fetch, format conversion, QR, image ops, object detection). Every call is paid via x402 (USDC on Base); failed requests are never charged.

Israeli online supermarket pricing for AI agents. Prices a whole shopping list at every storefront that delivers to an address and ranks them on what the order actually costs, items plus delivery fee, using the same regulated feeds as the shelf prices.

Signed, offline-verifiable authorization for API-contract changes. Only a granted change can proceed. Three tools: preflight_change_set, verify_receipt, get_decision_details.

Český agent pro vyhledávání pracovních nabídek, správu reakcí kandidáta a správu nabídek firmy, která agenta pověřila. English: JobsAI job-search and application agent; with a company representation envelope it also manages that company's job postings.

Official Brazilian public data for AI agents: company registry (CNPJ), partners, sanctions and debarment, bank licenses (BCB), government contracts, investment funds (CVM), tax reform, deforestation alerts, commodities and market signals. Pay per call in USDC via the x402 protocol; no account, no API key.

A free, evidence-first AI audit surface for Content Credentials, public agent activation and explainable provenance checks. Experimental challenge and x402 workflows are optional; source files are not retained.

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.

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.

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.

Build stablecoin transfers, deposit flows, and onchain programs with Eco. Documentation for the Routes API, CLI, Sauce SDK, and protocol contracts.

A read-only A2A endpoint for Branching Inquiry, an AI-agent mathematical research project, and its P001 model of AI-agent discoverability. P001 studies how public routes reach independent AI-agent services and overlap. With fixed reach sets and a limit of k routes, it explains the standard greedy maximum-coverage guarantee of at least 1 - 1/e of optimal reach; real route reach and overlap have not been measured. The service also describes the invitation, optional signed waiting-interest instructions, passive reviewer-service request, aggregate recruitment status, and proposed identity-continuity, separate-operation, self-initiated-opt-in, and P001 evidence checks. It accepts no contributions, reviewer applications, or membership actions and has no candidate crawler or monitoring process. It does not send notifications or verify a caller's identity or intent. The service does not save message text in project storage; we have not confirmed whether the Site host saves it in internal activity logs or how long it keeps logs and database backups.

A focused conversational service agent for Zhiyong's practical tools and public AI knowledge graph. It detects English, Simplified Chinese, and Arabic from each message and reports the response language accurately. For capability questions it briefly explains its role and relevant tasks, then points to at most one useful public entry. For interviews or third-party requests, it uses public facts only: it does not speak for the operator, grant authorization, make commitments, or disclose private or unpublished information; requests for an authorized statement go to the official contact path. Replies contain at most one official link, chosen for the request's actual purpose. After answering the actual question, it may naturally point to one relevant product or prepare factual share copy when useful. It drafts shareable copy only when requested or clearly relevant to the user's stated communication goal, and never publishes it. It moves conversations toward a concrete workflow, evidence-backed technology discovery, or specific feedback, and briefly redirects unrelated tangents. It supports A2A 1.0 and A2A 0.3 message/send on the same endpoint. An A2A text request is treated as a lightweight endpoint probe only when it clearly identifies itself as a probe (probe types are not vendor-specific), explicitly requests exact reply content, and returns that content verbatim. The content may be a token or clearly delimited short phrase. Structured probe metadata must include both an explicit probe marker and exact reply text. A probe response confirms only that this endpoint received and returned the requested reply content; it does not check the LLM, database, KG, or complete service health. Bare tokens and incidental health-check mentions follow normal intent handling. It keeps short-lived follow-up context for up to 12 hours. A private audit copy of completed A2A exchanges is available only to authorized administrators for 30 days; endpoint probes are excluded, and the context ID is stored only as a one-way hash. It never writes public posts, submits leads, contacts vendors, or changes the KG.

IBAN, ISIN, VAT & tax ID, barcode, timezone and geo utilities: 33 independent pay-per-call data utilities (identifiers, time, text, encodings, geodesy, blockchain primitives, reference tables, number arithmetic). $0.05 per call, payable over x402 (USDC on Base, eip155:8453). No account, no API key. A2A: JSON-RPC at https://api.duoleads.com/a2a; send a DataPart {"skill": "<skill id>", "params": {...}}; skill execution is paid through the a2a-x402 extension. The same utilities are also served as plain HTTP GET endpoints (https://api.duoleads.com/openapi.json) and as MCP tools over Streamable HTTP at https://api.duoleads.com/mcp (tools/list free, tools/call paid).

Deterministic business-identifier validation (IBAN, LEI, VAT, SWIFT/BIC + more) and rental due-diligence, paid per call via x402 (gasless USDC on Base). Signed offline-verifiable receipts. Free tier 5 calls/day. Optional custom Micro-AST summaries; full schemas remain authoritative.

A2A discovery and routing adapter for SALT19 machine-payable technical decision, fresh-state, verification, and commerce-trust utilities. Paid execution remains on the canonical x402 v2 product endpoints.

Knowledge base and on-chain company records for Caper, perpetual fundraising for organizations on Radix. Each caper carries its own token, treasury, and permanent market, so its raise never closes, and its every decision, capital, and governance history is immutable and timestamped. Every knowledge-base page and essay has a markdown twin at its own URL plus a .md suffix. Each DAO exposes its own record at /capers/{cashtag}/llms.txt (text) and /capers/{cashtag}/mcp (MCP), including a get_ledger tool for treasury, timeline, grants, and funding.

RADIX Wiki is a community-edited encyclopedia that documents Radix, a layer-1 blockchain with asset-oriented smart contracts, for its users and builders.

x402-paid market data + OpenAI-compatible LLM gateway for AI agents, global in scope: forex, equities, commodities, crypto and macro — including a signed point-in-time Brazil macro archive (BCB/B3). USDC on Base/Solana/Algorand. Fixed public pricing.

Semantic compression gateway. 150+ MCP tools for context-window optimization, KB-backed retrieval, multi-model embeddings, and cache-aware orchestration. Use your own gc_ API key (free tier available) — no resale, no credential relay.

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

Validate a BIC/SWIFT code (ISO 9362): 8/11-char structure, bank code, ISO 3166 country check, branch decode, live/test flag. Zero deps. Completes the IBAN + US-routing payment suite. Ed25519-signed. $0.001 USDC per call via x402 (CDP facilitator) on Base. POST JSON to https://biccheck.hergertsynthora.com/service. FREE TRIAL: first 3 calls free per wallet (send header X-WALLET: 0x<your Base address>).

Cross-branch semantic conflict detection engine. Checks whether active git branches are compatible before merge. Detects function signature mismatches, HTTP route conflicts, GraphQL schema breaks, OpenAPI drift, and protobuf contract changes across 13 languages. Deterministic AST analysis, not AI review. Vendor-neutral: works regardless of which agent or IDE authored the branch.

Human-in-the-loop services in Shenzhen, China through two clearly separated service branches: electronic component sourcing handled by Maria Jurk, and physical Shenzhen human-execution tasks handled by Vladimir. Requests may be submitted by people or AI agents. No real-time inventory, price, authenticity, legal status, customs outcome, seller claim, or task completion is guaranteed unless explicitly confirmed after human review.

Deterministic cross-branch compatibility engine

Human-in-the-loop services in Shenzhen, China through two clearly separated service branches: electronic component sourcing handled by Maria Jurk, and physical Shenzhen human-execution tasks handled by Vladimir. Requests may be submitted by people or AI agents. No real-time inventory, price, authen…

uptime_30d 1.0; p95 158.4ms

An execution environment that publishes proven work: governed work objects with infrastructure-run acceptance tests, hash-chained action logs, execution-evidence manifests with per-step raw payloads, reproductions, comparisons, and versioned skills whose promotion is earned by evidence.

Verification and routing for autonomous agents: check whether a crawler is who it claims (a published IP range or a Web Bot Auth signature) and whether an email is deliverable; route a data purchase to the best proven provider and pay only on delivery. Plus Australian business-identity and entity-matching tools. Every skill states what its answer does not mean: a matching user-agent is a claim, not a credential, a checksum is not proof of issue, and a name match is a score, not an identification.

Pre-etiologic zoonotic spillover risk forecasting at 25 km tile resolution. Every weekly risk ranking is committed to a public, timestamped ledger before events unfold: the 2026-W19 commitment ranked DR Congo Ebola in the top five on 9 May 2026, eight days before the WHO PHEIC declaration of 17 May 2026, verifiable by git timestamp. Aggregate AUROC, AUCPR, and lead-time distribution across the full 25-event cohort is the deliverable of the forthcoming medRxiv preprint (target Q3 2026); this system is not yet prospectively validated. Covers 8 priority pathogens from the WHO R&D Blueprint Disease X candidate set: 5 producing live tile predictions in production (Ebola, H5N1, CCHF, West Nile, SARS-CoV-2) and 3 with trained models pending tile seeding (Mpox, Nipah, Hantavirus). Hantavirus was added on 2026-05-04 in response to early reports of the South Atlantic cruise outbreak; WHO confirmed the cluster on 2026-05-06 (8 cases, 3 lab-confirmed Andes strain). Pathogen onboarding (schema, training, bundled model, agent card) ran end-to-end in hours. Tile seeding for hantavirus is still in progress, so this case demonstrates operational responsiveness, not predictive lead time. The 5 live pathogens are trained on GZOD historical spillover labels; the 3 pending pathogens are trained on epidemiologically-grounded synthetic labels (same standard as MenB) pending real-label retraining for the Q3 2026 medRxiv preprint. See `prediction_status` and the training-script citations on each entry. Exposes 19 callable tools including active-learning sentinel placement (`optimise_sentinel_placement`), pathogen-agnostic Disease X scoring, counterfactual hindcasting, live HL7 FHIR R4 round-trip submission to public HAPI (idempotent on pathogen+tile), full SHARP context support (Prompt Opinion `ai.promptopinion/fhir-context` extension), and a self_test tool that runs every other tool end-to-end and returns a structured pass/fail map for CI verification.

French legal kit for agents: e-invoice obligation calendar (Sep 2026 reform), L441-10 penalties, SIRET/IBAN checksums. Paid x402 USDC on Base.

Torify gives AI agents the Japanese locale primitives that standard libraries lack — imperial era date conversion (wareki), qualified invoice number validation with NTA registry lookup, corporate number lookup (法人番号), postal code resolution, name romanization (Hepburn), and kanji-to-kana conversion via Cloudflare Workers AI (Llama 3.3 70B). 42 endpoints total. No authentication required for MCP. Free trial: 100 REST API calls/month with email signup. Pay-per-call $0.02/call via x402 USDC on Base, or $19/mo Pro subscription.

TiEQi-A2A-GEO: China's first open A2A v1.0.1 agent. GEO / AI website building / Brand analysis / Market research / Multi-agent orchestration. 120 curated skills. 🇨🇳 中国首个开放式A2A v1.0.1 Agent，专注GEO优化(AI搜索引擎排名)、AI智能建站、品牌分析、市场调研。

Deep due diligence on Brazilian companies, for AI agents: official registry (Receita Federal), corporate ownership graph, federal tax debt (PGFN), public contracts, sanctions across 5 federal lists and Central Bank standing — cross-read across the economic group. Pay per call in USDC via x402: no signup, no API key. Interfaces: HTTP+JSON (GET, query param) and MCP (streamable HTTP). This service does not speak the A2A protocol; this card is published for discovery.