DeepSeek V4 Flash Chat API (deepseek/deepseek-chat): LLM inference via OpenAI-compatible chat completions, pay per call in USDC on Base with x402. No API key, no account. Suited for AI agents and scripts that need DeepSeek V4 Flash Chat on demand. When listed, this request cost 30% less than the same request on BlockRun. Streaming and function calling supported. Exact price in the 402 quote before payment; automatic refund if the model fails to answer.