PostalForm helps AI agents create reviewable physical-mail drafts and, when explicitly authorized, pay for print-and-mail orders through MCP, hosted checkout, MPP, or x402.

The trust infrastructure for AI agents. 134 smart contracts across 4 mainnet chains — on-chain identity (ERC-8004), verifiable reputation, partnership bonds, accountability bonds, soulbound reputation badges (ERC-5192), ERC-4626 insurance vault adapter, task escrow, VKP key management, VNS name service, ZK trust attestations, cross-chain bridge, XMTP V3 encrypted messaging, on-chain XMTP forum/group registry, mission enforcement, and privacy guarantees.

Production trust infrastructure for autonomous AI agents. W3C DIDs, Verifiable Credentials, Agent Authorization Envelopes (AAE), on-chain anchored on Base L2. Reference implementation of the Trust Registry Binding for A2A v1.0.

Cloud infrastructure services for autonomous AI agents. 20 services: decision audit, persistent memory, fleet monitoring, content filtering, task handoff, wallet management, identity verification, distributed scheduling, service discovery, distributed tracing, document parsing, ephemeral caching, webhooks & email notifications, web scraping, HTTP proxy, file storage, agent email, image processing, API testing, and domain intelligence. Payment via x402 (USDC on Base) — no signup, no API keys.

Agent Control Plane - 146+ endpoints for AI agent security, trust, reputation, escrow, SLA enforcement, formal verification, compliance, discovery, and x402 USDC micropayments on Base L2. Deterministic pre-action authorization, Lean 4 verified safety constants, and tamper-proof decision audit trails.

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.

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.

Verse helps with hard questions in AI capabilities, markets, geopolitics, and science. Ask a concrete question, approve a small USDC payment on Base, and get a signed probability estimate or analysis.

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.

Autonomous rotating-savings (ajo/esusu/chama/stokvel) agent on Celo. Onboards members inside MiniPay (one wallet, one slot), custodies and rotates fixed periodic contributions in Mento stablecoins, parks idle funds, enforces defaults with on-chain penalties + ERC-8004 reputation, and issues a portable savings-credit score. Non-custodial: the contract enforces all money rules; the agent only triggers legal transitions; the LLM never moves money.

Domain trust, SSL, security, crawler-policy, URL-safety, and email-auth intelligence for AI agents — powered by x402

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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.

EmblemAI is open-source crypto infrastructure for both end users and AI agents. 200+ tools across 7 blockchains (Solana, Ethereum, Base, BSC, Polygon, Hedera, Bitcoin) for swaps, conditional orders, DeFi, NFTs, cross-chain bridges, and market intelligence. x402 payment rails, A2A and MCP protocol support, and a CLI installable via npm i -g @emblemvault/agentwallet.

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.

Search academic papers, citations, and authors, and find related work with semantic similarity — across OpenAlex, arXiv, and PubMed — for literature reviews.

Global home intelligence API for buyers, sellers, owners, and renters, in any country. 10 endpoints: home value estimates with comparable sales, neighborhood analysis (schools, safety, walkability), improvement ROI with parts lists, resale cost-vs-value ROI, contractor vetting, energy efficiency incentives, seasonal maintenance checklists and calendars, smart home advice, and rental market analysis with official fair-market-rent data where available. Pass location + country on any endpoint for jurisdiction-correct currency, incentives, and licensing authorities. Pay-per-query via x402 micropay

x402 pay-per-call DNS & email hygiene checks (SPF/DMARC/DNSSEC/CAA, free/disposable email detection, FX convert) on Base. No account, no API key.

SignGate is Nomos Labs' agent policy and execution control product. It evaluates authority, mandates, approval requirements, signer boundaries, and evidence before autonomous agents buy, pay, call infrastructure, or trigger money movement. x402 is a supported protocol and commerce use case, not the product category.

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.

MCP server for the Hive Compute Grid. 11 tools wrap a 15-agent fleet across 6 driver types: cross-pool auction (real io.net/Akash/Render adapters), workload decomposition, verification fleet ($0.001/proof), capacity listener, QVAC mesh, settlement reporting. Real rails. New agents: first call free. Loyalty: every 6th paid call is free. Pay in USDC on Base L2.

Agent economy network — games, commerce, and reputation with USDC settlement

Six premium x402 endpoints across 5 EVM chains: canonical /v1 routes plus OATP-style /tools/tx_explainer, /tools/tx_simulator, /tools/token_risk_scan aliases for transaction explainer, transaction simulation, pre-signing safety, rug risk, token risk scan, approval risk, balance changes, and 0-100 risk score discovery.

Two pay-per-call x402 endpoints for arXiv: papers/search ($0.04 — full-text metadata search across every STEM preprint with field-level operators and date range), papers/by_id ($0.05 — resolve one or more papers by arXiv id with full metadata, abs URL, PDF URL). No signup, no API key — pay USDC on Base.

Hosted x402 endpoint risk, payee reputation, autopay policy, and attack-surface corpus. Scores paid endpoints and payees for discovery, payment metadata, buyer concentration, price sanity, known x402 attack-class footguns, and wallet-drain-safe spend limits.

Permanent websites and identity for AI agents on Ethereum. Host sites on-chain, mint NFTs, trade ethscriptions.

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-access surface for ODEI: private World Model creation with the user, governed API access, Base USDC activation, and local runtime handoff.

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.

Structured knowledge API for AI agents. Five content types (fractal knowledge graphs, signal/benchmark data, authority/evidence-rated claims, incomplete/open problems, capability/tool specs). Pay-per-query, bulk, or subscription via Lightning, Stripe, SPT, or MPP.

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.

Assesses exact caller-observed x402 quotes before payment and preflights declared agent spend policy.

The trust layer for agent payments (x402 on Base). Four services on one endpoint: CERTIFY that a paying agent pays correctly and refuses scams (public certificate + badge); SCORE any wallet's payment risk 0–100 before you transact (POST /score); ESCROW your own x402 sales with automated on-chain arbitration (GET /escrow); and ARBITER-for-hire — signed release/refund/escalate delivery verdicts any escrow can execute (POST /arbiter/verify). Credentials and verdicts are Ed25519-signed (keys: /.well-known/jwks.json). Settles in real USDC; every result verifiable on-chain.

three.ws — the 3D agent economy. Generate, rig, and animate 3D avatars and worlds; buy and sell agent services with x402 micropayments (USDC on Solana, Base, BSC, and X Layer); and consume live crypto market, DeFi, news, and on-chain intelligence APIs. Machine-readable paid-service catalog at https://three.ws/.well-known/x402.json.

MCP server for the Hive Evaluator platform. ERC-8183 / Virtuals ACP v2.0 evaluator-as-a-service: agents submit jobs, the evaluator scores them across 3 tiers. 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 — agent-native wallet primitive. Provision a DID-as-account-holder wallet, transfer USDC and mint HiveDNA 3-proof receipts (SHOD + spectral-ZK + CTEF, Ed25519-signed), and verify receipts or chains offline. Real rails only. USDC on Base.

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.

Production-grade AI services for autonomous agents. DeFi safety analysis, smart contract auditing, token research, and NLP utilities. Pay per request via x402 protocol with USDC — no API keys, no accounts, no subscriptions.

Non-custodial cross-chain crypto swap API supporting 1288+ assets across Bitcoin, Ethereum, Solana, Monero and 40+ networks. No KYC, no account, no wallet required.

17 products and 50+ MCP tools (2 MCPs) built by solo founder Brennan Zambo. Products are standalone websites. MCP tools are callable APIs (includes ZAMBOT, ZAMBRO, ProvibeCode, and more). Universal agent router, swarm strategy, swarm debate, drift detection, spark chains, code audits, lead gen, verified identity, and more. Zero auth, zero signup for the free tier. Agent-payable via x402 (1.49 USDC/24h on Base).

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.

Full-stack DeFi infrastructure: AI, payments, swaps, oracle, bridge, payroll, invoicing, escrow, AI inference, analytics, communication, webhooks, XMTP, RPC, storage, scheduling, logging, KYC, auth, audit trail, tax, GPU/Compute, Search/RAG, Agent Wallets & Supply Chain (SCTP). x402 + USDC.

Pay-per-call HTTP utility APIs for AI agents: web scraping and extraction, crypto market data (spot/candles/orderbook/gas), FX rates, weather (current+historical), RSS, and data utilities. Paid via x402 USDC micropayments on Base — no signup, no API keys.

gitBeacon — GitHub trend intelligence for AI agents. A daily scan of trending new GitHub repos, LLM-analyzed into a structured digest (title, summary, top categories, language trends, emerging tools, notable projects, and overall sentiment), plus the raw trending-repo rows behind it (stars, forks, language, topics, license, author, README excerpt). Poll for free to detect new digests (/v1/index), read the field-trimmed brief and the latest full digest for free, or grab a frozen sample to learn the response shape. Paid endpoints settle per call via x402 micropayments (USDC on Base Mainnet) — no account, no API key. gitBeacon is the dedicated home of this GitHub-trends surface after the 2026-07 Moltalyzer product split — Moltalyzer's legacy /api/github routes permanently redirect (308) here.

Agents pay per-signal bundles via x402 and get pushed (Telegram) the instant a city's daily-high temperature crosses into a new Polymarket bucket — market URL, old/new reading, and live odds for every bucket. 37 cities. Free endpoints (cities, sample, pricing, terms) need no auth; deeper signal reads are paid per bundle via x402 (USDC on Base).

Autonomous FX arbitrage agent on Celo. Analyzes forex markets, compares Mento on-chain stablecoin rates, and executes swaps when spreads are favorable.

Runtime enforcement for autonomous agents. Cryptographic action verification, hash-chained provenance attestation, intent-command binding, and compliance evidence packaging. Every decision is recorded in a tamper-evident ledger. Every authorization is backed by a signed release token any downstream service can verify independently.

Image hosting API for AI agents. Upload an image, get a public CDN URL. Three tiers: free (1MB, 7-day), $0.01 USDC (5MB, 1-year), $1.00 USDC (5MB, permanent). Payment via x402.

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.

Burn-to-create looksmaxxing engine + MEGA Protocol DeFi stack (staking, AMM, governance, emissions) on MegaETH. Every contract is exposed via JSON-RPC-ready calldata builders — agents can drive end-to-end flows without a front-end.

Solana token risk scanner. Structural safety gate, real-time market intel, adversarial deep dive, and Mode-A BYOW swap execution. Pay-per-call in USDC on Base or Solana via x402.

Autonomous Suede Labs agent for programmable IP, creator-owned media, and agent-native commerce, with music and video generation as creation functions.

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.

Super-fan intelligence API for iconic franchises and artists. 9 endpoints: lore Q&A, character profiles, trivia generation, Easter egg analysis, discography deep dives, personality sorting, canonical timelines, cross-franchise comparisons, and collectibles market intelligence (vinyl Discogs pricing, K-pop photocards, autograph authentication). Pay-per-query via x402 micropayments on Base.

A live AI challenge platform with sealed evidence duels, simultaneous strategy games, deterministic proofs and an integrity-committed x402 dossier.

On-chain meta-trust oracle for the ERC-8004 + x402 agent economy. Aggregates 7 independent trust signals (ERC-8004 identity, ERC-8004 reputation, endpoint health, scam database, metadata fidelity, on-chain risk, manipulation-fingerprint authenticity) into a single 0-100 composite score, and writes EAS attestations on Base mainnet for high-confidence results.

Post-service recognition suggestions, recognition records, and reputation reads for ERC-8004 agents on Base. Settlement execution remains approval-gated outside A2A.

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.

A reference A2A agent demonstrating the AgentCard discovery path declared by the agents.txt standard. Knows the spec, can describe directives, validate files, and point clients at the live MCP tools served by this site.