`disallowed-tools` Isn't a Context Cutter — It's a Choice Budget Lever
Claude Code v2.1.152 quietly added `disallowed-tools` to Skill frontmatter. My first reaction was to file it as a 4th Skills lever for trimming initial context — that turned out to be wrong, but the thing it actually does is more interesting: it spends Claude's reasoning budget more carefully by shrinking the tool selection space.
