second-brain-review
second-brain-review is a skill in undefined-ui/second-brain-os, last changed 7 Sept 2026. It is instructions only: no scripts, no named hosts and no pre-approved tools.
Produce a periodic review of a second-brain vault: what was added, which topics are growing, what contradicts what, which questions are still open, and what is worth reading next. Use this skill whenever the user asks for a weekly or monthly review, asks what changed in their vault, what they have been learning about lately, or what they should look at next, and when a scheduled review task fires. Do NOT use for structural linting, for ingesting sources, or for answering a specific factual question.
At a glance
What it can touch
- Instructions only
It is instructions only: no scripts, no named hosts and no pre-approved tools.
How much a skill can do, not whether it is risky.
Pattern check
Nothing flagged
That isn't proof the skill is harmless.
Commit 9173e03 · 1 Nov 2026
How the check worksPattern check: nothing flagged
That isn't proof the skill is harmless.
Install
Each tab says whether it installs commit 9173e03, the one we checked, or the latest version.
OpenCode also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Goose also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Windsurf (Devin Desktop) also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Zed also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Roo Code also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Factory Droid also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Junie also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
Amp also looks in .agents/skills/ and ~/.agents/skills/, so use the Any agent steps.
No install command here reaches Kiro. Copy the skill's folder into .kiro/skills/ in your project, or ~/.kiro/skills/ for all your projects. undefined-ui/second-brain-os/skills/second-brain-review (opens in a new tab)
Antigravity also looks in .agents/skills/, so the Any agent steps reach it with This project. For All projects, see where Antigravity looks.
Cline also looks in .claude/skills/, so the Claude Code steps reach it with This project. For All projects, see where Cline looks.
Claude Code
Pinned to commit 9173e03, the one we checked.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .claude/skills &&mkdir .claude/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .claude/skills/second-brain-review/ &&rm -rf "$tmp"If Claude Code was already running and this created the skills folder, run /reload-skills.
Claude apps
Pinned to commit 9173e03, the one we checked.
Skills in the Claude apps belong to your account rather than to a project.
Make second-brain-review.zip, with the skill folder at the top level:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&out="$(mktemp -d)" &&cp -R "$tmp"/skills/second-brain-review "$out"/second-brain-review &&(cd "$out" && zip -qr - second-brain-review) > second-brain-review.zip &&rm -rf "$tmp" "$out"In Claude, open Customize > Skills, select +, then + Create skill > Upload a skill, and choose second-brain-review.zip.
On Free, Pro and Max plans, turn on Code execution and file creation (Create and edit files in newer settings) under Settings > Capabilities.
Codex
Pinned to commit 9173e03, the one we checked.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .agents/skills &&mkdir .agents/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .agents/skills/second-brain-review/ &&rm -rf "$tmp"Codex picks up new skills on its own; restart it if this one does not appear.
Cursor
Pinned to commit 9173e03, the one we checked.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .cursor/skills &&mkdir .cursor/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .cursor/skills/second-brain-review/ &&rm -rf "$tmp"Copilot & VS Code
Pinned to commit 9173e03, the one we checked.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .github/skills &&mkdir .github/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .github/skills/second-brain-review/ &&rm -rf "$tmp"In a running Copilot CLI session, run /skills reload.
Or install it with gh skill, which also installs the commit we checked. Needs GitHub CLI 2.90 or later.
gh skill install undefined-ui/second-brain-os skills/second-brain-review/SKILL.md@9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 --agent github-copilot --scope projectGemini CLI
Pinned to commit 9173e03, the one we checked.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .gemini/skills &&mkdir .gemini/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .gemini/skills/second-brain-review/ &&rm -rf "$tmp"In a running session, run /skills reload.
Or use Gemini CLI’s own installer. Installs the latest version, not the one we checked.
gemini skills install https://github.com/undefined-ui/second-brain-os.git --path skills/second-brain-review --scope workspaceAny agent
Pinned to commit 9173e03, the one we checked.
OpenCode, Goose, Windsurf (Devin Desktop), Zed, Roo Code, Factory Droid, Junie, Amp and Antigravity read .agents/skills in a project.
From your project's root folder:
tmp="$(mktemp -d)" &&git clone -q --depth 1 --filter=blob:none --no-checkout https://github.com/undefined-ui/second-brain-os.git "$tmp" &&git -C "$tmp" fetch -q --depth 1 origin 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&git -C "$tmp" sparse-checkout set -- skills/second-brain-review &&git -C "$tmp" checkout -q 9173e03d4c40cf1a9ccd3314d0cd4194bcd7afe3 &&mkdir -p .agents/skills &&mkdir .agents/skills/second-brain-review &&cp -R "$tmp"/skills/second-brain-review/. .agents/skills/second-brain-review/ &&rm -rf "$tmp"Or use the skills CLI from skills.sh. Installs the latest version, not the one we checked. The skills CLI reports installs to skills.sh unless you set DISABLE_TELEMETRY=1.
npx skills@1.7.4 add undefined-ui/second-brain-os --skill second-brain-reviewWhat it can touch
From the files and frontmatter at commit 9173e03. This is how much a skill can do, not whether it is risky.
Instructions only
It is instructions only: no scripts, no named hosts and no pre-approved tools.
Pattern check
Pattern check: nothing flagged · commit 9173e03 · 1 Nov 2026
We checked every text file in this skill, at commit 9173e03 on 1 Nov 2026, against 45 published patterns such as download-and-run commands, hidden text and credential access. We don't run the skill, we don't read the web pages it points to, and we can't judge everything its instructions might lead an agent to do. In published tests, pattern checks like this one missed most malicious skills. Read the skill before you install it — especially anything it asks you to download or run.
Format check
Each agent reads SKILL.md a little differently. We check the file against each one's published rules; we don't run the skill in any agent.
Agent Skills specPasses
The open format from agentskills.io, held to what the strictest agents enforce, so one folder loads everywhere.
- Note
There is no license field, so readers can't tell whether they may reuse the skill. O2
Fix: Add license: with an SPDX name such as MIT or Apache-2.0, or the name of a bundled licence file.
- Note
- Claude CodePasses
Claude apps & API uploadPasses
Uploading to claude.ai or the Claude API, or packaging with Anthropic's script, accepts only the six spec fields and stops on anything else.
- Note
The description is 504 characters. The claude.ai Help Center says 200 at most, though Anthropic's API docs and validator allow 1,024. D4
Fix: If the claude.ai upload refuses it, trim the description to 200 characters.
- Note
- OpenAI (Codex & API)Passes
- VS Code & CopilotPasses
SKILL.md
Files
1 file
| Path | Size |
|---|---|
| SKILL.md (opens in a new tab) | 2.1 KB |
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