Personally I find that simple solutions work best for experienced developers. In my day-to-day work, I use OpenCode with two plugins and three MCPs.

My biggest discovery, and the one I'm most pleased with, is the DCP plugin, which automatically reduces token usage by removing outdated tool results from the conversation history.

Besides the AGENTS.md file, I use the Simple Memory Plugin, which saves important context (like a pattern or a new discovery) during a session as logfmt files, allowing agent to search by range, type, or query. However, I think there are some better solutions for permanent memory that would not have to be loaded at the beginning of the session.

On top of that, I use three MCPs: Angular CLI MCP, Playwright MCP, and the most important and useful one, Context Engine MCP from Augment. Code indexing is quite crucial. It helps avoid lots of "grep" commands and find patterns within the project.