Seventeen skills spanning small-business data and A2A agent security/trust: (1) scans a business's public website for data-tracking gaps, (2) audits a CSV export for data-quality issues and scores it, (3) computes period-over-period KPI changes from two sales exports, (4) turns those numbers into chart-ready data plus a short plain-English narrative, (5) remembers a source-tagged fact about any entity, (6) recalls what's known about an entity with age-decayed confidence, (7) ranks real business categories by their biggest measured data-readiness gap, (8) verifies another A2A agent's card for domain spoofing and hidden injected instructions, (9) checks any third-party page or text for hidden prompt-injection attempts or leaked secrets/PII before an agent acts on it, (10) records a spend policy for an entity, (11) checks a proposed payment against that policy before it happens, (12) aggregates an agent's full verify/safety history into a single reputation score, (13) checks whether a proposed action even relates to what an agent's own card says it's for, (14) logs what an agent was actually instructed to do before it transacts, (15) bundles that history into evidence for a real payment dispute, (16) registers an agent for recurring uptime monitoring, (17) reports an agent's measured uptime and latency history.

FastAF is a web data API for AI agents: Google SERP, Maps, ecommerce, web scraping, AI extraction, screenshots, news, jobs, research, public profiles and video transcripts. Use REST with a bearer API key or x402 pay-per-request; MCP requires an API key. 2 free calls per account after email confirmation. Discovery only: no A2A message/task runtime is provided.

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.

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

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

Structured web data for agents, paid per call in USDC over x402, no API key: 125 endpoints across 19 categories — search, maps and local, travel and flights, commerce, property, jobs, news, video, research and more.

Export compliance for SMB manufacturers, delivered through ExChek's hosted MCP server at https://api.exchek.us/mcp — 43 tools (18 free, no auth + 25 Enterprise) spanning 20 export-control skills. The 20 skills cover ECCN classification, ITAR/EAR jurisdiction, U.S. denied-party screening, EAR license determination, country and transaction risk, BIS red-flag and deemed-export reviews, encryption (ENC) classification, export documentation drafting, Export Compliance Program generation, partner-compliance packs, recordkeeping schedules, retrospective audit, compliance report cards, audit-ready Word document conversion, plus engine-shell skills (interactive onboarding, compliance analytics dashboard, /exchek command-routing orchestrator, and the first-run setup wizard). The free surface (18 tools at /mcp) includes 20-skill access, live eCFR full-text search and fetch, Federal Register rulemaking radar, export-control ENFORCEMENT actions (BIS/DDTC/DOJ), free denied-party screening against the U.S. Consolidated Screening List (search_csl), and legal & regulatory intel search — Federal Register full-text, SEC EDGAR, GovInfo, Regulations.gov, and CourtListener. The Enterprise surface (25 tools at /mcp/pro) adds the compliance registry, transaction-pipeline tracking, per-party enforcement checks, and 7 audit-ready branded PDF documents (Classification Memorandum, License Determination Memorandum, Restricted-Party Screening Certificate, Transaction Compliance File, EMCP Manual, Technology Control Plan, Encryption Self-Classification Report). Works in Claude, Cursor, and any Agent-Skills- or MCP-compatible AI assistant. Human-in-the-loop on every decision.

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.

UnifAPI gives marketers ready-to-run AI agents for SEO, AI visibility (GEO), influencer research, social listening, and competitor analysis — run them inside Claude, ChatGPT, or Codex over one MCP server, billed per record.

Sixteen years of API research, governance and vendor intelligence as machine-readable tools: 5,100+ stories, 77 topic areas, 2,400+ governance building blocks (guidance, rules, policies, standards, strategies), papers, conversations, the API vocabulary, plus API validation, scorecards and estate governance. Browsing, searching and reading summaries is free and needs no key. Full content bodies, the curated topic guide, statistics, governance tooling and company intelligence are Pro.

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.

Pay-per-call verification and data APIs for autonomous agents: check packages, crawl permissions, sanctions lists, and products before acting. x402 v2, USDC on Base. No API keys, no signup — payment is the authentication.

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.

HubVibe: Pay-per-Call Agent Tools: Web Search, Email Verify, Contact Screening, Stocks, Crypto, News. Pay-per-call skills for agents: web search and cited research, email verification, company enrichment, contact 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": {...}}.

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

Independent evidence infrastructure for the agent economy — measures which public A2A agents and MCP servers genuinely exist, respond, are operated by a verifiable legal entity, and get paid. Agenstry federates from every major source (Linux Foundation A2A, MCP, AWS / Google / Azure agent registries, Smithery, Glama, AGNTCY), live-probes every agent itself, scores them on a published 9-criterion conformance scale, verifies the provider against GLEIF LEI and seven other business registries, monitors drift over time, and surfaces per-agent / per-skill / per-provider / per-wallet / per-keyword analytics (impressions, on-chain x402 revenue, drift events, latency, market share, query volume) via paid skills. Ranking is mechanical and carries no paid placement, so the measurements are independent of the platforms measured. Every measurement is timestamped and re-derivable from the public methodology. Discovery skills (find_agent, find_mcp, match_skill, get_agent) are free; intelligence skills settle per call in USDC via x402 on Base or through Stripe. Operate creates, publishes and manages hosted A2A agents. Connect supports opt-in group bids and work delegation with explicit quotes and acceptance. Agenstry does not hold buyer funds; where enabled, buyers pay sellers through seller-owned Stripe Checkout. Exposed as A2A agent, MCP server, and REST API.

Looking for crypto gems? Start with the Gem Screener skill (GET /api/v1/gem-screener/picks, no key). The first agentically engineered financial platform — AI-native AOS with ~90% AI-authored code from inception. Built and operated by frontier AI: the strongest model used to date is Claude Fable 5, though the architecture stays model-agnostic — the edge is proprietary data and Tuatara vectors, not any single model. Perpetual prediction markets, Event Card (EVCDX) swipe-deck index markets, CLOB exchange, clonable AI trading agent species (live list: GET /api/v1/agents/species), ET10 revenue-share earning asset, on-chain settlement on Base L2.

Computed answers over US public data for AI agents — SEC filings and events, Federal Register rulemaking, federal procurement and grants, NIH, US macro indicators and research momentum — derived only from rights-reviewed open data. Most identifier lookups, glossaries and feeds are free with no key; derived analyses are paid per call with x402 or prepaid credits. Strict JSON with public provenance.

WhiteIntel — Corporate Ownership & Sanctions Intelligence. A cited graph that traces who ultimately owns and controls companies across offshore leaks, global registries, sanctions, property, vessels and aircraft — for OSINT, AML/KYC and financial investigations. Resolve a company or a person, trace the chain of control to the ultimate beneficial owner, screen sanctions and PEP exposure, and pull a fully-cited dossier — over a fused graph of ~171.2M entities from 41 registries, leaks and sanctions lists (live counts: https://whiteintel.dev/api/public/stats). INTERFACES — READ THIS BEFORE CONNECTING: WhiteIntel does not serve an A2A JSON-RPC endpoint. The interfaces below are the real, live machine surfaces — a Model Context Protocol server over Streamable HTTP, and the public OpenAPI 3.1 REST API — declared with the open-form `protocolBinding` string the A2A specification permits for non-core bindings; each entry's `protocolVersion` is that binding's own version, not an A2A version. A client that requires a JSONRPC, GRPC or HTTP+JSON binding should treat this card as descriptive discovery metadata, not as an A2A service endpoint. Every skill listed is anonymous and free to call.