seems really cool! although, one question i have is why not keep agent() alongside the new primatives? it seems v4 removed agent() entirely rather than offering it with all of act(), observe(), extract().

We removed agent because so many great harnesses are available in the ecosystem. Instead of keeping it, we decided to make Stagehand v4 better integrated with popular harnesses, both at the Coding Agent level (Codex, Claude Code) and frameworks level (Eve, Deep Agents, Mastra, etc)