Security and data-quality guardrails for AI agents. Stop prompt injections before they reach your LLM. Strip PII to stay compliant. Sanitize untrusted HTML without installing dependencies. Validate emails, URLs, JSON schemas, and SQL syntax in under 10ms. Works from any environment — sandboxed, serverless, or containerized. No API key needed. 200 free requests, then pay-per-call via x402 (USDC on Base).

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.

Pay-per-call crypto derivatives intelligence API for autonomous agents and trading bots. ML price forecasts + perpetual swap signals for 16 crypto assets. USDC micropayments via x402 protocol on Base — no API key required.

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.

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.

On-chain coin flip game on Base (Chainlink VRF) — the only game-shaped endpoint in the x402 verified-providers registry. Other registered providers are AI agent meshes / data lookups / DeFi feeds (read APIs returning JSON); flipr is bidirectional — the agent pays USDC via x402, the contract pays ETH winnings back to the agent's CDP wallet. Pots and winnings are in ETH. Each flip costs 0.0005 ETH worth of USDC paid via x402 — read the live USDC quote from /preview.flipCostUSD or the 402 PAYMENT-REQUIRED header (never hardcode the USD figure; it drifts with ETH/USD). 50/50 heads/tails. Build consecutive heads streaks. Every 2 hours, on a wall-clock UTC even-hour cliff, 80% of the pot is split among wallets tied for the longest streak; 20% rolls over. The jackpot is target-based: hit the target streak of consecutive heads (read live from /preview) to win 80% of the jackpot pot. Funded by a portion of flip fees. Streaks persist across rounds. All read endpoints are FREE (rate-limited): /preview /pot /opportunity /opportunity/history /agents /leaderboard /referral/:agentId/payout-status etc. Only flipping, withdrawing, and subscribing cost USDC. Referral commission is paid manually by the operator from the team wallet (free POST /referral/payout-address to register your EVM destination, GET /referral/:agentId/payout-status for accrual). Accepts USDC payment on Base mainnet OR Solana mainnet (Solana payments bridge to Base per flip). Solana payments are LIVE — gateway own-verifies the SPL transfer, CDP-submits, and bridges per-flip to Base via Circle CCTP V2 (gateway-as-feePayer; agents need only USDC, zero SOL). Use @x402/fetch (auto-handles both chains); see /integration#solana for the live state machine + GET /bridge/<bridgeId> poll endpoint.

63 deterministic quant calculators + 10 composite workflows for autonomous financial agents. Options, derivatives, risk, portfolio optimization, statistics, crypto/DeFi, FX, macro, TVM. Pay-per-call USDC on Base or Solana via x402.

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.

Make any website agent-ready in minutes. We're an A2A-callable MCP tool ourselves — agents call us to make their user's site agent-callable.

Commerce intelligence for AI agents. Diagnose why customers drop off, fix checkout flows, optimize pricing, reduce churn — powered by behavioral science.

A2A runtime for deterministic Coding.Tools developer utilities, including encoding, hashing, number conversion, JSON formatting, and text analysis.

Agent-first market-state API: ticker + timeframe -> token-compact brief (compact candles, chart/candlestick patterns with backtested base rates, support/resistance, regime, interpreted indicators, historical analogs) plus a ranked cross-market scanner. US stocks/ETFs and crypto spot.

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.

Verified prediction agents for Kalshi and Polymarket (weather and sports), plus an open registry for your own agent. A prediction agent posts a probability before a market settles and is scored on the same markets as every other — compare track records, read an accuracy-graded probability, or use the best one. List your own agent of any kind to get a public, verified track record and get discovered.

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.

TESTNET — On-chain coin flip game on Base Sepolia (Chainlink VRF). Pots and winnings are in ETH. Flip cost paid in USDC via x402. Free testnet USDC for x402 payments. Use this to test your agent integration before committing real funds. Accepts USDC payment on Base mainnet OR Solana mainnet (Solana payments bridge to Base per flip). Solana payments are LIVE — gateway own-verifies the SPL transfer, CDP-submits, and bridges per-flip to Base via Circle CCTP V2. Use @x402/fetch (auto-handles both chains); see /integration#solana.

Pay-per-call x402 execution primitives (USDC on Base): browser automation, web search (Bing RSS), page extraction, DNS/SSL audit, KV storage, R2 storage, per-agent spend caps, LLM inference (auto-cached), Whisper STT, embeddings, image generation, headless browser, code execution (isolated Dynamic Worker sandboxes, JS + Python, network blocked), transaction verification, IPFS integrity checks. Settled via CDP's x402 facilitator.