Single /codex-runtime invocation could spawn 'codex --version' up to 3
times (state report, enable gate, success message). Each spawn is ~50ms,
so the cumulative cost wasn't a crisis, but it was wasteful and turned a
trivial slash command into something noticeably laggy on slower systems.
Refactored to lazy-once via a closure over a nonlocal cache. First call
spawns; subsequent calls in the same apply() reuse the result.
Behavior unchanged — same return shape, same error handling, same install
hint when codex is missing. Just one subprocess per call instead of three.
Two regression-guard tests added:
- test_binary_check_cached_within_apply: enable path → call_count == 1
- test_binary_check_cached_on_read_only_call: state-report path → call_count == 1
Total tests for /codex-runtime now 30 (was 28); all 143 codex-runtime
tests still green.
Teknium
0a94d8e73f