BlockBeats News, April 21, Blockchain analytics company Nansen announced a comprehensive upgrade to its on-chain data API, introducing a "pay-as-you-go" model based on the x402 protocol and PayAI infrastructure. Users can now instantly query wallet profiles, token flows, and smart money signals through small USDC payments, without being bound by monthly subscriptions, forced approvals, or long-term contracts.

Nansen pointed out that the traditional subscription model is extremely unfriendly to AI agents and developers—AI agents often need intermittent queries and then enter idle states, developers face uncertain future needs during prototype testing, and researchers are locked into unnecessary fixed costs. The new solution is built around the open payment standard x402: when requesting access to a paid endpoint, the server returns a 402 Payment Required status code indicating the amount, currency, and chain information. The client completes an on-chain USDC transaction and provides the payment receipt to access the data. The entire "request-invoice-payment-deliver" process is fully programmable, and AI agents can autonomously make payments.

Nansen's newly opened API is divided into two pricing tiers, both settled in USDC on either the Base or Solana chain: the basic tier charges $0.01 per call and provides core data such as token filtering, wallet balances and history, DEX trades, P&L summaries, etc.; the advanced tier charges $0.05 per call and unlocks proprietary signals such as smart money net flow, holding distribution, P&L leaderboards, and more. In practical applications, the cost of running a smart money alert system is approximately $0.15 per run, wallet profile analysis costs about $0.07, and token research costs approximately $0.07.