hook: --ultra-compact and --skip-env are accepted but never propagate into the rewritten command #2984

Description

rtk hook claude accepts --ultra-compact and --skip-env (they're documented in rtk hook --help), but neither flag has any effect: the rewritten command emitted to Claude Code is byte-identical with and without them. The flags are silently dropped.

This matters because the hook is the only path most Claude Code users ever exercise — commands are rewritten transparently, so a user never types rtk by hand. Configuring "command": "rtk hook claude --ultra-compact" in ~/.claude/settings.json looks like it enables Level 2 savings, but it is a no-op. There is no error and no warning, so the setting appears to work.

Repro steps

for f in "" "--ultra-compact" "--skip-env"; do
  echo '{"tool_name":"Bash","tool_input":{"command":"next build"}}' \
    | rtk hook claude $f \
    | python3 -c 'import sys,json;print(json.load(sys.stdin)["hookSpecificOutput"]["updatedInput"]["command"])'
done

Output:

rtk next     # no flag
rtk next     # --ultra-compact
rtk next     # --skip-env

Same result for every command type I tried (git status, jest, tsc --noEmit, eslint src, grep -rn foo src, npm run build).

Expected

The hook should propagate its flags into the rewritten command, e.g.

rtk hook claude --ultra-compact   ->  rtk next --ultra-compact
rtk hook claude --skip-env        ->  rtk next --skip-env

rtk next (and the other subcommands) already accept both flags — rtk next --help lists them — so the target side is in place; only the hook's rewrite is missing them.

If the flags are intentionally unsupported on the hook path, they should be rejected at parse time or removed from rtk hook --help rather than accepted and ignored.

Actual

Flags are accepted, produce no change, and emit no warning.

Version / environment

• rtk 0.43.0, macOS arm64 (Darwin 24.6.0)
• Hook configured as a PreToolUse / Bash matcher in ~/.claude/settings.json

Note

Distinct from #2369, which is about the top-level -u shorthand not being implemented on the main CLI. This report is about the long flags being accepted by rtk hook claude and then not reaching the rewritten command.