AI agents can seamlessly integrate with TradFi APIs (such as Stripe and core banking systems) to automate payments, balance inquiries, and transaction execution. There are use cases within regulatory-compliant environments. For example, AI agents can access real-time account data via APIs to execute predefined tasks. Some banks have already deployed agentic AI, which only requires standardized interfaces to operate, and this is efficient enough for non-cross-border or low-frequency scenarios. However, in cross-border scenarios, crypto is essential. More importantly, if APIs rely on centralized institutions, it's difficult for AI agents to have autonomous "identities" (e.g., without human guarantees): they cannot open bank accounts, and in TradFi, human co-signers are often required. In other words, encryption is indispensable for the autonomy of AI agents. The evolution of the AI agent economy from "reactive" to "proactive" requires micropayments, agent-to-agent transactions, and decentralized settlement. Cryptocurrency can provide a permissionless layer: AI agents can create wallets, payment services, or earn income without IDs, Social Security numbers, or human intervention. For example, AI agents can autonomously pay API calls or data. While TradFi APIs are fast, they are hampered by KYC and centralized bottlenecks, preventing them from supporting instant, intermediary-free machine-to-machine transactions. Traditional APIs are expensive and slow to settle; crypto supports microtransactions, making it suitable for the high-frequency micro-activity of AI; crypto can solve the identity and reputation issues of AI agents. ERC-8004 or KYA provides AI with on-chain identity, building cross-platform reputation, allowing AI to "finance" or trade without a bank account. Furthermore, crypto integrates DeFi and on-chain data (such as real-time market signals), enabling AI agents to execute complex strategies (such as automatic rebalancing). Speculating, AI agents will likely adopt a "layered" architecture: TradFi APIs handle compliant transactions, while crypto serves as a settlement/coordination layer. Google and Cloudflare are building stablecoin protocols specifically for AI agent trading. Regulation (such as the GENIUS Act) will drive the bridging of TradFi and DeFi, but the permissionless nature of crypto will allow AI to become more independent. If AI agents scale up (routing trillions of dollars in transactions), ignoring crypto is tantamount to missing out on the infrastructure of the "robot economy".