cross-reviewlisted

# Cross-Provider Review Get a second opinion on a change from a **different model than the one that wrote it**. This exists so heterogeneous review holds in both directions: `/bs:quality` already spawns Codex when Claude drives, but a Codex session had no way to reach Claude. Without it, Codex-authored work is reviewed by Codex — the reviewer and the author are the same model, and agreement means nothing. **Usage**: `/bs:cross-review [--base <ref>] [--provider claude|codex|auto] [--timeout <seconds>]` ## When to use this - You are in a Codex session and want a Claude review before merging. - You are in a Claude session and want a Codex review outside a full `/bs:quality` run. - A review came back clean and you want to know whether that survives a different model. This is an **advisory** review. It does not stamp a `Reviewed-By:` trailer and does not satisfy the merge gate — `/bs:quality` remains the only path that produces merge evidence. Say so when reporting results; do not imply a change is cleared to merge. ## How it runs Everything routes through the existing provider runner. Do not shell out to `claude` or `codex` directly — `provider-run.sh` already handles the deadline, sandboxing, structured error classification, exhaustion/unavailability exit codes (74/75/76), and unwrapping the CLI's JSON envelope. **Never pass `--provider auto` from this skill.** `auto` resolves via `bs_provider_invoker`, which reports _which provider is currently running_ — `CODEX_THREAD_