Building Shadow-Signal: Bridging the Gap Between On-Chain Intelligence and Execution with Nansen CLI

In the fast-moving world of decentralized finance, the "time-to-trade" is everything. Traditionally, a trader sees a "Smart Money" move on a dashboard, manually verifies the contract, and then heads to a DEX to execute. By the time that loop finishes, the alpha is often gone. I built Shadow-Signal, an autonomous agentic script that collapses this entire workflow into a single loop using the new Nansen CLI. The Architecture Shadow-Signal is built using a Node.js wrapper around the Nansen CLI, designed to act as a "Sentinel" for high-conviction Smart Money moves on Solana and Base. The logic flows through three distinct layers of the Nansen ecosystem: The Discovery Layer (nansen research): The script polls the smart-money netflow endpoint. Unlike a broad scan, I used the --fields flag to limit data transfer and focused on the 24h timeframe to identify sustained accumulation rather than transient noise. The Reasoning Layer (nansen agent): This is where the "Agentic" part comes in. Raw dat