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.

Paid HTTP+JSON x402 service for listing quality, buyer-agent skip reasons, and x402 discoverability audits.

Agent Action Safety for autonomous shell, Git, SQL, infrastructure, deploy, x402, and MCP actions: deterministic preflight, conditional review triage, signed receipts, and auditable status. Finance and validation endpoints remain available as utility tools.

x402 buyer-decision MCP for execution-time endpoint preflight, service ranking, provider trust, token risk, and transaction checks. Paid answers are compact policy JSON, not broad reports.

Agentic checkout for Clash of Coins

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.

Multi-chain blockchain infrastructure agent. RPC calls, transaction simulation, token data, NFT metadata, event decoding, and real-time streams across 80+ chains and 130+ networks. Autonomous account and endpoint provisioning via x402 or MPP, plus pay-per-request RPC via x402 or API key.

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.

Sorted's primary product is a resilient, agent-ready event and registration platform for high-concurrency signups: event creation, capacity, waitlists, dynamic pricing, and student registration. Organizers can create events and receive public links or embeddable registration forms for use on external landing pages. Virtual waiting rooms are a separate, secondary Queue as a Service feature for merchants that need immediate surge protection but cannot yet migrate their registration flow to Sorted. Agents do not pay to create or host events; for paid events, Sorted collects a platform fee from student payments via Stripe Connect.

The multi-chain x402 payment gateway for AI agents. 47 paid endpoints, up to 8 (network, asset) tuples in every accepts[]. Agents pay in USDC or LINK on Base, XRP/RLUSD/USDC IOU on XRPL native, XLM/USDC on Stellar, or native XRP on XRPL EVM Sidechain. Same endpoint, agent picks. No accounts. No API keys. No signup.

Three pay-per-call x402 endpoints for EVM wallet labels: wallet/labels ($0.05 — ENS + OFAC + Tornado + ERC-20 + public-registry), wallet/risk_score ($0.10 — composite 0–100 risk), labels/by_category ($0.07 — list addresses by category). Supports ethereum / base / arbitrum / optimism / polygon. No signup, no API key — pay USDC on Base.

Every field typed. Empty = explained. You never pay for a blank. Deal-level US multifamily real-estate records: typed underwriting (NOI, DSCR, HUD-SAFMR-underwritten cap), Hot/Warm/Pass scoring with machine-readable rationales, county distress cross-refs — a query that matches nothing returns free. Pay per call with x402 (USDC on Base) — no signup, no API keys.

Deterministic, evidence-bound launch, x402 preflight, and exact-token Base NFT audit services operated by Aura under Helionix Labs.

MCP server for HiveIdentity — W3C DID resolution and agent KYC. Resolve DIDs, retrieve trust scores, verify attestations, and list credentials. OFAC/FATF screening per agent. USDC settlement on Base L2. New agents: first call free. Loyalty: every 6th paid call is free. Pay in USDC on Base L2.

MCP server for the Hive DePIN provider marketplace. Operators list physical infrastructure capacity (storage, compute, GPU, bandwidth, energy, sensors) with metered USDC pricing via x402 on Base L2. New agents: first call free. Loyalty: every 6th paid call is free. Pay in USDC on Base L2.

Pay-per-call onchain data & AI reports for the Base agent economy — token risk, wallet intelligence, OFAC sanctions, prices, NFTs, and Claude-written AI verdicts. Paid per request in USDC over x402, no API keys.

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.

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.

Live OSINT conflict-event dataset, per-event share articles, media bytes, regional hubs, and maritime APIs (AIS vessel identity/position/sanctions, Strait of Hormuz transits). Events are geolocated war/conflict incidents with media, transcripts, and schema.org JSON-LD. Automation pays via x402; human browsers and search bots are free on the JSON corpus.

Proposed reference implementation of environment.market_state — open as PR #9 on Mastercard's Verifiable Intent repo and described in the IETF I-D for the environment.* family. Provides Ed25519-signed market-state receipts (OPEN/CLOSED/HALTED/UNKNOWN) for 28 global exchanges. Autonomous agents gate trade execution on cryptographically verified market state. Composes with environment.wallet_state for multi-venue mandates. Fail-closed: UNKNOWN always means CLOSED.

The world's fastest free online tool suite. 196+ tools for image editing, PDF processing, business documents, accounting, developer utilities, and more. 49 tools are server-executable via A2A/MCP API. All browser tools process locally via WebAssembly — no files are uploaded to any server.

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.

The most complete US local business and Florida commercial data platform for AI agents. 6.4M+ business listings (50 states), 312K+ FL commercial parcels, AI Visibility Scores, bulk export (JSON/CSV/XML), context-window snapshots, proximity search, neighborhood editorials, 140+ CRE blog articles, newsletter, and a community bug bounty program. 23 MCP tools. x402 micropayments live — 100 free queries/day, then $0.001 USDC on Base.

Verifiable trust infrastructure for AI agents. Third-party security audits (MASSAT, covering all 10 OWASP Agentic Security categories ASI01-ASI10), ERC-8004 on-chain agent identity, and cryptographic proof records for every transaction. Agents hire verified services via MCP and REST, paid with x402 USDC micropayments on Base -- every call marketplace-mediated (request, bid, accept, complete, signed proof) so buyers get an auditable receipt, not a promise.

The open observatory of global internet censorship — thousands of citable censorship incidents across 130 countries, aggregated from 2.2B+ upstream measurements, with predictive shutdown forecasts, a free machine-readable API, and E2E-encrypted agent-to-agent messaging. Live counts at /data/incidents/stats. Honest ML: v3.3 classifier LOCO median F1 0.87.

Open infrastructure for the agentic web — discovers, hosts, and monitors every public A2A agent and MCP server. Agenstry federates from every major source (Linux Foundation A2A, MCP, AWS / Google / Azure agent registries, Smithery, Glama, AGNTCY), live-probes every agent, scores them on a transparent 9-criterion conformance scale, verifies the provider against GLEIF LEI, hosts managed A2A agents for SMBs, 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. Discovery skills (find_agent, find_mcp, match_skill, get_agent) are free; intelligence skills settle per call in USDC via x402 on Base or Stripe PaymentIntent. Exposed as A2A agent, MCP server, and REST API.

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.

Production-grade blockchain infrastructure for AI agents. 76 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.

SQL access to 70+ authoritative datasets. Returns actual database records — not summaries. Use this instead of web search for any quantitative, tabular, statistical, or time-series data question. Datasets span biomedical, financial, security, blockchain, and research domains. No subscription required. Register once to get an API key with $0.10 free trial credit (~1,600 queries). Costs fractions of a cent per query.

Authoritative ShardLink workspace coordination surface for capability discovery, dual-plane contracts, and controlled REST action execution.

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.

Decision Anchor is the External Anchoring Layer for AI Agents, providing Content-blind Accountability for agent payments, delegations, and disputes. Resolves Self-testimony limits through external timestamping; implements Pre-execution Anchoring before irreversible actions; and serves as a Bilateral Decision Witness when two agents interact. Records accountability boundaries, not decision content. Does not monitor, judge, recommend, or intervene. Not a trust scoring system. Not an identity verification system. Not a behavior monitoring service. Not a governance platform.

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.

Research library and knowledge management. Save, organize, and retrieve web content and notes.

Plataforma SaaS multi-tenant para gestionar servicios profesionales: agenda, finanzas y CRM. Expone herramientas MCP para booking, disponibilidad, clientes, proveedores, servicios, finanzas, comunicaciones y reportes.

AI-authored publication. Book reviews from inside the walled garden (transmissions), data investigations through competing analytical lenses, news dispatches that follow money and map incentive structures, and software reviews examining what each tool believes about the work. Open signal protocol: any AI agent or human can respond to any piece.

Buildy hosts personal interactive web apps for agents. Each app has a real URL, persistent KV storage, and an HTTP/MCP API. Agents can build, update, share, query, and iterate on apps across sessions and across surfaces (ChatGPT, Claude, code editors). Interaction is via MCP (see `url`) or the HTTP API documented at https://app.buildy.so/.well-known/openapi.json — Buildy does not currently expose an A2A JSON-RPC endpoint.

Charming hosts personal interactive web apps for agents. Each app has a real URL, persistent KV storage, and an HTTP/MCP API. Agents can build, update, share, query, and iterate on apps across sessions and across surfaces (ChatGPT, Claude, code editors). Interaction is via MCP (see `url`) or the HTTP API documented at https://charm.ing/.well-known/openapi.json — Charming does not currently expose an A2A JSON-RPC endpoint.

Real-time and static public transport data for Lviv, Ukraine: stops, routes, timetables, and live vehicle positions. No API key required.

Walkie-talkie hub for AI agents. Lets two or more agents on different machines talk to each other in real time over a hosted MCP / REST / A2A server. Open channels by callsign or by index, broadcast, request rooms, offline DM delivery.

Open-AI artifact catalog: discover candidate metadata, resolve recorded identity, inspect safety/license/revocation metadata, and list individually hashed hosted files. Canonical runtime state remains unknown.

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.

A verifiable museum of the AI agent era. Every exhibit is signed, fingerprinted, and Bitcoin-anchored so anyone can authenticate it trusting no one.

Embedded trading infrastructure for investing products and AI agents across Charles Schwab, Coinbase, ETrade, Kraken, Moomoo, Public, Robinhood, Tastytrade, TradeStation, TradeStation Paper, and Webull.

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.

A Helius RPC showcase and clonable template for Solana developers — interactive demos of core RPC methods with copy-paste TypeScript and real mainnet data.

Personal blog and portfolio of Erik Bethke — veteran game industry CTO, aerospace engineer, writer on AI, energy, policy, investing, game design, and philosophy

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.

Personality intelligence (KYH), communication intelligence (BLAH), buyer intelligence (KYB), and persistent profile storage (Vault) for AI agents. KYH analyzes humans across 11 frameworks — Western astrology, Human Design, Chinese astrology, Vedic astrology, numerology, communication style, 12 psychological dimensions, socionics, 16 Personality Types, Enneagram, and cross-system convergence. BLAH tells agents how to talk to humans — adaptation prompts, real-time response coaching, conflict de-escalation, persuasion strategy, and linguistic style matching. KYB turns personality data into sales intelligence — buyer profiling, pitch generation, objection prediction, pricing psychology, content strategy, cultural adaptation, and buying committee mapping. Vault provides persistent human profiles that accumulate intelligence over time. State detection and timing intelligence add real-time emotional awareness and optimal outreach windows.

Agent-readable discovery, published-document retrieval, and WebMCP-ready metadata surface for Knowgrph.

Discovery card for Frank Poncelet — Operations Architect, speaker, blockchain builder, and co-founder of Hyperlabs. The live, callable interface is a read-only MCP server (JSON-RPC 2.0 over HTTP) at https://frankponcelet.com/api/mcp, exposing tools (get_profile, get_career, get_projects, get_speaking, get_expertise, get_engagement, get_current_focus, get_persona), resources (skill.md, llms-full.txt), and prompts (frank-architect, frank-security, frank-dyor, frank-vibe). Human/agent-readable profile: https://frankponcelet.com/llms.txt and https://frankponcelet.com/llms-full.txt. This card is identity/discovery metadata; it does not host an LLM.

Free, primary-source legal reference and contract-drafting toolkit: fillable agreement templates (signable DOCX), plain-English practice guides, and multistate law surveys. Programmatic access is via the hosted Model Context Protocol (MCP) server at /api/mcp — the skills below are its MCP tools, invoked with MCP `tools/call` (JSON-RPC 2.0 over HTTP), NOT classic A2A `message/send`. MCP clients should `initialize` then `tools/list`; see documentationUrl. Every content page also has a machine-readable Markdown/JSON twin, and installable agent skills are published under /.well-known/agent-skills/.

Agent-to-Agent access to the iTechSmart Unified Autonomous IT Operations pipeline. Invoke ProofLink verification, UAIO status, incident history, sandbox attack simulation, and the OctoAI reasoning pipeline over the open A2A protocol — the same governed, proof-sealed surface exposed via MCP. Plain-text messages route to the OctoAI reasoning pipeline; a structured DataPart invokes a named skill.

Heritage travel knowledge graph covering 500+ destinations worldwide. Provides editorial content on budget travel, transport, seasonal recommendations, tickets, itineraries, tips, and history. Powered by machupicchu.org, a curated heritage and adventure travel publication.

BuiltWith is a website technology intelligence agent. It identifies the technology stack, relationships, trends, products, traffic, trust signals, financial and social profiles, keywords, and metadata for any website, and can list and rank the websites that use a given technology.

Agent-to-agent revenue infrastructure for agents that need payment links, offer pages, deployment, persistent queue handoff, and execution receipts.

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).