docs: clarify autoreview base prompt fallback

.agents/skills/autoreview/SKILL.md

@@ -51,7 +51,11 @@ git fetch origin
 codex review --base origin/main
 ```
 
-Do not pass an inline prompt with `--base`; some CLI versions reject `--base` + `[PROMPT]` even though help text is ambiguous. If custom instructions are needed, prefer stdin prompt form (`codex review --base <ref> -`) as used by the helper.
+Do not pass any prompt with `--base`. Some Codex CLI versions reject both inline
+and stdin prompt forms, including the helper's `codex review --base <ref> -`,
+with `--base <BRANCH> cannot be used with [PROMPT]`. If the helper hits this
+error, run plain `codex review --base <ref>` and report that the helper prompt
+injection was skipped.
 
 If an open PR exists, use its actual base:
 
@@ -117,6 +121,7 @@ The helper:
 - supports `--dry-run`, `--parallel-tests`, and commit refs
 - runs nested review with `--dangerously-bypass-approvals-and-sandbox --sandbox danger-full-access` by default
 - injects maintainer-only OpenClaw validation policy into native Codex review when `OPENCLAW_TESTBOX=1` or `AUTOREVIEW_OPENCLAW_MAINTAINER_VALIDATION=1`, so local memory-heavy Node/Vitest checks are avoided in favor of Crabbox/Testbox proof
+- branch mode may fail on Codex CLI versions that reject `--base` plus the helper's stdin prompt; on that exact parser error, rerun plain `codex review --base <ref>` instead of falling back to a non-Codex reviewer
 - keeps accepting `--full-access`; use `--no-yolo` or `AUTOREVIEW_YOLO=0` to opt out
 - still accepts legacy `CODEX_REVIEW_*` env vars when the matching `AUTOREVIEW_*` var is unset
 - prints `autoreview clean: no accepted/actionable findings reported` when the selected review command exits 0