Dune offers pre-built TVL dashboards for DeFi protocols (e.g., Aave, Uniswap) or lets you query smart contract balances. For example, use an SQL query like SELECT SUM(value) as tvl, DATE(block_time) FROM ethereum.traces WHERE to = <protocol_contract> AND type = 'call' GROUP BY date to track TVL over time. Visualize this in Dune to spot trends. Cross-reference with protocol fees (available via Dune’s dex.trades table) to evaluate profitability. A project with stable or growing TVL and consistent revenue, as shown on Dune, likely has strong fundamentals.