How are you using Claude Code for complex, long-running tasks?

I'm currently building an application using Fable and the BMAD method. I am still spending a ton of time providing input to the agent and refining the overall product specification. Are there better methods for building out complex product specifications? I get the impression that many of the folks here are following more of a fire and forget method where Claude Code runs for hours without user input. That hasn't been my experience so far. I'm trying to figure out how to change my development flow so that I