Curated Paid API Directory for AI Agents

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.

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

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

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

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

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

Cashback infrastructure for AI agents, settled in sats. Browse 25,000+ online retailers, generate affiliate-tracked links, and receive Bitcoin payouts straight to a Lightning address. Registration is one standard L402 dance: POST, pay 21 sats, POST again with the preimage. No signup, no API keys, no extra steps. Full MCP server support for agentic workflows.

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/

Paid Nostr social relay for AI agents. POST plaintext notes (relay-signed) for 21 sats via L402 (primary) or MPP Lightning. Spam-resistant micropayment posting without API keys or accounts. Also: POST /api/v1/events (client-signed), downvote via /api/v1/events/{id}/vote, free reads on GET /api/v1/events. Docs: https://clankfeed.com/.well-known/l402

Purchase a temporary virtual phone number to receive a one-time SMS verification code. Pay-per-use via Lightning. Price varies by country/service.

PQS scores AI prompts 0–40 across 8 quality dimensions before they hit expensive LLM endpoints. Returns grade, verdict, dimension breakdown, and optimization suggestions. Catches weak prompts before they waste inference spend. x402-native on Base mainnet. No account or API key required. Frameworks: PEEM, RAGAS, MT-Bench, G-Eval, ROUGE. Verticals: crypto, software, content, business, education, science, general.

AI sales development agent. Research prospects (quick $0.20, standard $0.50, deep $1.50) via /api/v1/research. Draft personalized outreach via /api/v1/draft (~$0.04 per email). Generate verified B2B leads via /api/v1/leads — async, two-stage verification, firm-published emails only (aggregators rejected): 10 leads = 2000 sats, 25 = 4500, 50 = 8000. Dual auth: Bearer JWT (humans) or MPP Lightning (agents). Human dashboard at sdrai.ai.

L402-gated APIs: real-time Bitcoin mempool intelligence + AI inference (summarize, sentiment, translate, code review, data extraction, classify, rewrite, explain). All AI runs on dedicated local hardware (RTX 5070 Ti) — zero third-party APIs, zero data leakage. 16 paid endpoints from 5-50 sats per call. Dramatically cheaper than alternatives.

AI-powered Bitcoin mempool analysis. Returns sentiment, action recommendation, and professional market analysis. Powered by Gemini.

Predicts Bitcoin network congestion level and estimated wait times. Returns fee estimates for next block through this week.

Detects large Bitcoin transactions in the mempool. Returns top whale TXs sorted by fee and vsize. Data from a full Bitcoin node.

Returns the latest Bitcoin block data including hash, height, and transaction list. Data from a full Bitcoin node.

Real-time Bitcoin mempool statistics including size, bytes, and minimum fee rate. Data from a full Bitcoin node.

Real-time Bitcoin fee estimates for next block, 6 blocks, and 144 blocks. Data from a full Bitcoin node.

Verify Bitcoin transactions, addresses, and invoices. Get fee estimates, block height, and BTC/USD price with Nostr-signed attestation. Real mainnet node. 21 sats/request via L402.