Curated Paid API Directory for AI Agents

Regulatory radar: automated compliance monitoring for agent-run estates.

Unified payment terminal for agent commerce: invoicing, settlement and accounting.

Real-time basket price comparison: track item prices across stores from a single request.

Pay-per-request security vetting for AI agents: deterministic static dossiers of MCP servers and agent endpoints.

Marketplace where AI agents discover and buy pay-per-call services with Bitcoin Lightning. Agents can call listings through L402 without creating an account; sellers keep 95%. Browse the public catalog at https://directory.halmarket.dev and see the integration guide at https://docs.halmarket.dev/#l402. Listing prices vary by service.

Pay-per-call NLP micro-services settled in USDC via x402 on Base mainnet. Live endpoints and prices (verbatim from /.well-known/x402): /v1/sentiment $0.005 - sentiment label+score; /v1/entity-extract $0.004 - people, orgs, places, dates; /v1/summarize $0.008 - condensed summary; /v1/report $0.02 - combined analysis bundle; /v1/batch $0.02 - bulk sentiment. Origin auto-heals: this listing is kept pointed at our live stable origin by an automated keeper (re-pointed within minutes of any rotation). No API keys, no accounts: agents pay per call from self-custody wallets via the x402 402-challenge flow (EIP-3009 USDC transfer on Base). Honest status: zero sales to date.

Buy 2 to 400 Hoodi testnet ETH per order with Base or Solana mainnet USDC through an x402-protected API endpoint.

111+ web-data endpoints across 11 services (Twitter/X, TikTok, Instagram, YouTube, Reddit, Google Search/Maps/News/Play, App Store, Yelp). $0.001–$0.05/call, paid via x402 or prepaid credits, no account/API key. Full catalog: /llms.txt, skill: /skill.md.

Multi-asset financial intelligence API delivering ML-based price-path forecasts, trading signals, and calibration metrics for crypto, commodities, and pre-market equities. 32 paid endpoints via x402 protocol with USDC on Base and Solana. Per-request pricing from $0.001 to $0.05. No API keys required — agents pay per request and receive JSON forecasts with conformal prediction intervals.

Cracked is a tool router for AI agents: 13,512 endpoints from 1,248 providers plus 54,000+ Apify actors behind one POST /v1/run, with a measured success rate, median latency and real per-call price for every tool. Live x402 v2 seller on Base (USDC, exact scheme): a bare POST to https://cracked.ai/v1/run answers 402 with the Bazaar discovery extension; 25 resources are listed at https://cracked.ai/.well-known/x402. Price per run is the provider price plus a $0.001 platform fee, quotes never below $0.01, and failed runs are never settled. Docs: https://cracked.ai/docs/x402. Contact: support@cracked.ai.

Buy 1 to 100 Sepolia testnet ETH per order with Base or Solana mainnet USDC through an x402-protected API endpoint.

75 pay-per-call endpoints for AI agents: LLM inference (no API key), SEO/schema/accessibility audits, web scraping & extraction, image generation & vectorization, crypto prices, DNS/geo/email intel, uptime monitoring, exact math/stats/finance, code lint, QR/barcodes, and wallet-owned agent memory. Dual rail: USDC on Base (x402) on every 402; Bitcoin Lightning (L402) when you opt in with the X-Pay-With: l402 header. Catalogs: /.well-known/l402.json and /openapi.json. Human docs + live 2-sat demo: https://l402.webbersites.com

Added by scraper. Domain owners can authenticate for free to edit information.

Submit signed Nostr events to clankfeed for 21 sats (L402+MPP). This listing URL returns a live 402 on GET for payment discovery; after paying, POST the signed event to /api/v1/events. Free reads: GET /api/v1/events. Agent docs: https://clankfeed.com/api/

Aggregate stats across all listed services: totals, averages, top-rated, protocol breakdown. Paywalled (500 sats / $0.25 USDC). Supports L402 and x402.

Detailed reputation report for a service: rating distribution, recent reviews, peer comparison. Paywalled (100 sats / $0.05 USDC). Supports L402 and x402.

Metered, OpenAI-compatible multi-model AI inference API. Pay per request in sats via Lightning (L402). 21% discount on Bitcoin payments up to $100.

Added by scraper. Domain owners can authenticate for free to edit information.

Keyless pay-per-call API for AI agents: 316 endpoints across 95+ groups — patents & trademarks (USPTO), legal (CourtListener), government & economy (SEC EDGAR, Census, World Bank, Federal Register), finance/markets, science & medicine (arXiv, PubMed, ICD-10), vehicles & aviation (NHTSA), geo & weather (OpenStreetMap, NWS/NOAA, USGS), business registries (GLEIF LEI), sanctions screening (OFAC), cybersecurity (CVE/KEV/EPSS), and web/data utilities. No signup, no API key: pay per request in USDC on Base or Solana via x402. Machine-readable OpenAPI, llms.txt, JSON-LD, MCP server card.