docs: register /sync-gbrain in AGENTS.md and docs/skills.md

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

AGENTS.md

@@ -63,6 +63,7 @@ Invoke them by name (e.g., `/office-hours`).
 | `/benchmark-models` | Cross-model benchmark for skills (Claude, GPT, Gemini side-by-side). |
 | `/cso` | OWASP Top 10 + STRIDE security audit. |
 | `/setup-gbrain` | Set up gbrain for cross-machine session memory sync. |
+| `/sync-gbrain` | Keep gbrain current with this repo's code; refresh agent search guidance in CLAUDE.md. |
 
 ### Browser + agent integration
 

docs/skills.md

@@ -42,6 +42,7 @@ Detailed guides for every gstack skill — philosophy, workflow, and examples.
 | [`/codex`](#codex) | **Second Opinion** | Independent review from OpenAI Codex CLI. Three modes: code review (pass/fail gate), adversarial challenge, and open consultation with session continuity. Cross-model analysis when both `/review` and `/codex` have run. |
 | [`/pair-agent`](#pair-agent) | **Remote Agent Bridge** | Pair a remote AI agent (OpenClaw, Codex, Cursor, Hermes) with your browser. Scoped tunnel, locked allowlist, session token. |
 | [`/setup-gbrain`](#setup-gbrain) | **Memory Sync** | Set up gbrain for cross-machine session memory sync. One command from zero to live. |
+| [`/sync-gbrain`](#sync-gbrain) | **Keep Brain Current** | Refresh gbrain against this repo's code; teach the agent when to use `gbrain search`/`code-def` over Grep. Idempotent; safe to re-run. |
 | | | |
 | **Safety & Utility** | | |
 | [`/careful`](#safety--guardrails) | **Safety Guardrails** | Warns before destructive commands (rm -rf, DROP TABLE, force-push, git reset --hard). Override any warning. Common build cleanups whitelisted. |