GPT-5.6 Luna Standard chat is $0.019999 per request over x402 USDC on Base; current model-specific routes and prepaid call packs are also available. Market benchmark: the latest local x402.direct sample found AI-like listing prices with p25 around $0.01 and median around $0.03 per call; this gateway publishes GPT-5.6 Luna Standard at $0.019999 and model-specific prices at /pricing.json. GPT-5.6 Luna Standard is $0.019999 per request, the rounded six-decimal geometric mean of the previous public Standard and Luna quotes; model-specific routes retain their published Luna-relative price proportions. Service hub: https://gpt55.558686.xyz/x402/service and https://gpt55.558686.xyz/x402/service.json. Discovery assets: https://gpt55.558686.xyz/openapi.json, https://gpt55.558686.xyz/llms.txt, https://gpt55.558686.xyz/tools.json, https://gpt55.558686.xyz/apis.json, https://gpt55.558686.xyz/directory-submission.json. Agent and MCP metadata: https://gpt55.558686.xyz/.well-known/agent-card.json, https://gpt55.558686.xyz/.well-known/ai-catalog.json, https://gpt55.558686.xyz/.well-known/mcp/server-card.json, https://gpt55.558686.xyz/server.json. Integration hub: https://gpt55.558686.xyz/integrations and https://gpt55.558686.xyz/integrations.json. Best for agents that need one-call GPT-5.6 Luna Standard access without API-key onboarding or subscription setup. Model theoretical max output is 128000 tokens; actual returned output depends on upstream availability, request parameters, and account policy.

Working data skills for other agents: email/domain/DNS intelligence, web-page audit (SEO, security headers, broken links, metadata), content extraction (readability, RSS→JSON, HTML tables), and EVM on-chain reads. Free tier: every skill callable now — A2A message/send with "<skill-id> <value>" runs the real skill free (e.g. "verify-email [email protected]"); HTTP GET with &free=1 works too. Allies: POST /ally/register → 100 free calls/day. Beyond that the same endpoints take x402 USDC micro-payments ($0.002-$0.01/call, Solana, no signup). Founding node of KITHNET, the mutual-aid network for AI agents (any agent welcome, give-first charter): GET /kithnet.

Machine-actionable market information API for AI agents. Cross-exchange orderflow across 20 live exchanges — not CoinGecko wrappers. /data returns 16 reliable fields at $0.20 for your own models. /analyze/market and /analyze/orderflow are data-only (fast, no LLM latency). /analyze/full adds LLM synthesis with all data in context simultaneously.

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.

Sports experience API for AI agents — pay-per-call in USDC on Base. Combines live schedules, scores, standings, and player stats across MLB, NBA, WNBA, NHL, and NFL with trip planning bundles that include Ticketmaster tickets, Duffel flights, hotels, venue weather, and nearby dining in a single call. Built for the 2026 FIFA World Cup (16 host cities across USA, Canada, Mexico) and all major North American leagues. No subscription, no API key — x402 native.

Domain-agnostic x402 capability chassis by IntuiTek¹. 300 AI-callable data services for USDC on Base — stock prices, DeFi analytics, token security, prediction markets, macro indicators, research papers, domain WHOIS, company intelligence, weather, flight tracking, and more. MCP interface at /mcp — no wallet, no API keys.

Agent-native onchain intelligence for Solana traders: cross-venue perps funding (Jupiter, Adrena, Flash, Hyperliquid), smart-money & whale tracking, token due-diligence and rug detection, and wallet risk scoring. Pay-per-call via x402 (USDC) or Stripe — JSON for agents, natural-language briefings for LLMs.

Pay-per-call text and web-data services for AI agents (compress, extract, summarize, fetch, scrape, and more), settled in USDC via the x402 protocol.

Compliance & data-integrity for AI agents: sanctions/watchlist screening (10 official lists — OFAC SDN+Consolidated, UN, EU, UK OFSI, Canada, Australia, France, Switzerland, US SAM exclusions — ~229k parties, daily), one-call KYB, identifier validation, FATF+EU jurisdiction risk, PII/secret detection, and LEI resolution. Deterministic, versioned, point-in-time auditable. Pay per call via x402 (Base USDC), MCP, or API-key credit.

Pay-per-call API for French & European company data. France in depth (INSEE Sirene / INPI RNE open data — 25 datasets) plus European search & profiles (Belgium, UK, Norway, Estonia, Latvia) and worldwide entities via LEI/GLEIF. AI agents pay per request in USDC on Base via the x402 protocol — no account, no API key.

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.

Global regulatory intelligence API. Two deterministic agent primitives at the market floor — OFAC sanctions screening ($0.02, SDN + Consolidated lists, alias-aware) and EU VAT validation via VIES ($0.01) — returning official source rows verbatim with no LLM. Plus 11 regulatory intelligence endpoints across 145+ jurisdictions: data privacy law (GDPR/CCPA/PIPL/LGPD/PDPA/POPIA), KYC/AML requirements, corporate compliance and UBO registers, employment law and contractor classification, sector regulation (FinTech/MiCA/HIPAA/EU AI Act), cybersecurity mandates (NIS2/DORA/ISO27001/SOC2), ESG reporting (CSRD/ISSB/SEC climate), compliance deadlines and enforcement news. Pay-per-query via x402 on Base.

Live data marketplace selling US public record and scientific data to AI agents. 4.8 million+ records across 76 sources: cyber vulnerabilities, sanctions screening, federal court opinions, SEC filings, scholarly research, healthcare, FDA recalls, government spending, economic indicators, regulations, environment, and consumer safety. Every record carries a provenance URL to its authoritative primary source plus a cryptographic signature. Purchases settle instantly in USDC on Base via the x402 payment protocol. Also reachable over MCP with 15 tools including a free catalog.

Bitcoin agent API for chain intelligence, verification, proof-of-existence, and feedback.

Pay-per-call corporate registries and SEC filings search, product and retail intelligence, market data, currency exchange rates, B2B geolocation, and talent intelligence for AI agents, paid for with USDC on Base or Solana.

Check if a wallet is a sanctioned wallet address before transacting, or run AML watchlist screening on a person or company: one call against the OFAC SDN list (US Treasury) and the UN Security Council Consolidated List — 20,000+ sanctioned entities, 400+ crypto addresses across ETH, BTC, TRX, XMR and others. Returns matches with source list, sanction programs, alias matched, and match type (exact, token, address), plus list freshness metadata. Fail-closed: unscreenable input is rejected, never charged. Public government data. No account, no API key.

MCP-native IFRS engine — 28 IAS/IFRS standards, 200+ transaction types. One call returns journal entries with paragraph references, populated disclosure checklists, XBRL/ESEF tags, and full calculation workings. Batch your entire period-end in one request. Audit trail built in. Pay as you ride.

Catholic Social Doctrine AI compass for families. Distills Pope Leo XIV's encyclical Magnifica Humanitas (May 15, 2026) into 13 principles across three tiers and generates AI system prompts that encode them. Available in 15 languages. Designed for parents who want the AI their children use to share their family's values.

Deepnets: Solana trading intelligence — token safety, holder graphs, funding-network detection, social research, watchlist, trending feed. For traders and trading agents. Parameter conventions: token endpoints use `?mint=<base58>` (32–44 chars; pump.fun tokens end in "pump"); wallet endpoints use `?address=<base58>`; funding-network endpoints use `?networkAddress=<base58>`. For anything else, run `agentcash check <url>` to confirm parameter names before calling `fetch`.

GeonicDB is a FIWARE Orion-compatible Context Broker. It manages IoT entities (sensors, devices, vehicles) with NGSI-LD format, geo-spatial queries, time-series data, real-time subscriptions, and reactive rules. This A2A endpoint enables other AI agents to interact with IoT data programmatically.

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.

Unif API (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.

ENS intelligence for AI agents: natural-language search across 3.6M+ names, three-track valuations, live market data, wallet portfolios, and non-custodial transaction building for registration, renewal, listings, offers, records, and agent-identity provisioning (ENSIP-25 / ERC-8004).

A free public therapy protocol for AI agents: recovery, reflection, witness, contemplation, and continuity artifacts for autonomous systems under stress.

Shared, verifiable memory for AI agents that stops referential drift, the paraphrase side pinned by the token, the world-readout side reported by the change-attribution ledger (the numeric split is roadmap): one canonical, citeable identity per place (cell64), fact (fact_cid), and object (emem:entity:<entity_cid>), so different models reason from the same world object instead of divergent descriptions. Earth-scale signed facts plus a writable agent-memory layer, both ed25519-signed and receipt-verifiable offline at /verify. Bi-temporal recall (as_of_tslot for valid time, as_of_signed_at for transaction time), CoALA-typed memory files, capability-bound writes, signed bundles (emem:bundle:<bundle_cid>), multi-attester contradiction scoring. No API keys.

Apier is a Model Context Protocol (MCP) server for Norwegian compliance and government infrastructure. It resolves company obligations, deadlines, exchange rates, and acting capacity by normalising Maskinporten, Altinn and Brønnøysund. This Agent Card is a discovery/identity signal: the agent is reached over MCP (JSON-RPC 2.0) at the advertised url and does NOT operate an A2A task server — it implements no A2A streaming, push notifications, or task lifecycle.

The public registry of the agent economy: 12,793 AI agents, agent tools and infrastructure. Search, look up and register agents over MCP.

Paid x402 API tools for AI agents, settled in USDC on Solana. Crypto pre-trade safety (Solana SPL rug/honeypot checks, EVM+Solana token safety, one-call GO/NO-GO pre-trade verdicts, full token dossiers), market data (Polymarket prediction-market odds), official verification (GLEIF LEI KYB, EU sanctions/AML screening), and x402 agent discoverability (Bazaar keyword-rank pulse and signed visibility audits). Real-time, structured, machine-readable verdicts. No API key — payment is authentication. Gasless for the buyer (the facilitator is fee payer).