replying to the question introduced with your edit at the root: mcp servers tend to inject too many tokens into the context, that might not be relevant for the task at hand. ex: sentry's mcp is useful if you are collecting context for a bug in production, but is hardly useful later when fixing the bug, at that point you'd probably want treesitter, or if you are working on a new feature you might want to pull details from github issues, or jira tickets.

the consensus seems to land on making the right tools available to the agent, and let it pick which ones to use for the task, this typically means cli tools like git, gh, linters, a cli for your cloud/hosting provider, etc.

that is where skills come in: they bootstrap some context about a task the operator wants to complete. skills use progressive disclosure — each Read() adds more context, but the agent controls what to load-up and what to ignore, and skills can also come with scripts that facilitate actions relevant to the task.