AI Second Brain
charlie947/ai-second-brain
Walks the user through Charlie Hills's AI Second Brain + Karpathy Wiki setup from the MarTech AI newsletter.
Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first.
Install Second Brain Chat Import
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-import --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/second-brain-chat-import .claude/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .claude/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-importType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-import --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/second-brain-chat-import .agents/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .agents/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-import --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/second-brain-chat-import .cursor/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .cursor/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/undefined-ui/second-brain-os.git --path skills/second-brain-chat-import--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-import --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/second-brain-chat-import .gemini/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .gemini/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-importInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/second-brain-chat-import .github/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .github/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install undefined-ui/second-brain-os second-brain-chat-import --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/undefined-ui/second-brain-os.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/second-brain-chat-import .opencode/skills/second-brain-chat-import && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "second-brain-chat-import" agent skill from https://github.com/undefined-ui/second-brain-os/tree/main/skills/second-brain-chat-import into .opencode/skills/second-brain-chat-import/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "second-brain-chat-import", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
second-brain-chat-import- GitHub stars
- 999
- Token cost
- ~527 tokens
- SKILL.md length
- 215 words
- Files
- 1
- Skills in repo
- 23
- Repo updated
- First seen
- Licence
- MIT
At a glance
Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first.
- Works in 5 steps: Convert with… → Privacy pass. List conversations… → Triage the rest into three piles: worth… → …
- The user has exported their Claude
- SKILL.md covers Core rule, Workflow, Output format and Calibration
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Second Brain Chat Import is an agent skill from undefined-ui/second-brain-os. Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first. Use this skill when the user has exported their Claude or ChatGPT history, asks to import old conversations, or asks what in their chat archive is worth keeping. Do NOT use for ingesting a single pasted conversation, or for any material the user has not explicitly asked to bring into the vault.
Its SKILL.md is about 530 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Knowledge Management, covering Second brain. It works with OpenAI. The repository describes itself as: An AI second brain that maintains itself. Full guide, starter vault, agent skills and scripts for a self-organizing knowledge base in Claude Code and Obsidian. The licence is MIT.
When your agent uses it
- The user has exported their Claude
- ChatGPT history
- Asks to import old conversations
- Asks what in their chat archive is worth keeping
Example prompts
- “/second-brain-chat-import”
Workflow steps
5 steps, taken from the first numbered list in SKILL.md.
- Convert with scripts/chat_export_to_md.py into one file per
- Privacy pass. List conversations touching health, money, other people's
- Triage the rest into three piles: worth ingesting (they worked something
- Report the lists. Move nothing yet.
- On approval, ingest the first pile, with the instruction that these are
What it can do on your machine
Read from SKILL.md and the folder at commit d6861cc. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Second Brain Chat Import loads about 527 tokens when it runs. Until then it costs about 109 tokens; SKILL.md has 215 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from undefined-ui/second-brain-os at commit d6861cc, republished under its MIT licence (© undefined-ui). 215 words, ~527 tokens.
Download SKILL.mdSave it as
.claude/skills/second-brain-chat-import/SKILL.md (or your agent's skills folder).- name
- second-brain-chat-import
- description
- Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first. Use this skill when the user has exported their Claude or ChatGPT history, asks to import old conversations, or asks what in their chat archive is worth keeping. Do NOT use for ingesting a single pasted conversation, or for any material the user has not explicitly asked to bring into the vault.
Import chat history
Chat history is the most underrated source a person owns and the most sensitive. It records their reasoning, not just facts, and it also records things they would not want in a file that gets synced, committed and backed up.
Core rule
Privacy pass before triage, triage before ingestion. Never ingest an export wholesale.
Workflow
- Convert with
scripts/chat_export_to_md.pyinto one file per conversation, filtering out short exchanges. - Privacy pass. List conversations touching health, money, other people's private information, or confidential work. The user decides; you delete nothing on your own.
- Triage the rest into three piles: worth ingesting (they worked something
out, decided something, or got an explanation that landed), worth archiving
in
raw/, and delete. - Report the lists. Move nothing yet.
- On approval, ingest the first pile, with the instruction that these are the user's own thinking: build pages around what they were working out and what they concluded, not around the assistant's explanations.
Output format
Converted: <n> conversations (<n> skipped as too short)
Privacy review needed: <n>
<title> - <why>
Worth ingesting: <n>
<title> - <what it worked out>
Archive only: <n>
Delete suggested: <n>Calibration
Expect roughly nine in ten conversations to be throwaway lookups. A triage that recommends ingesting most of the export has not filtered.
Record dates on every page. A position from two years ago is not a current belief, and the vault has to be able to tell the difference.
© undefined-ui, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in skills/second-brain-chat-import of undefined-ui/second-brain-os.
Open the folder on GitHubat commit d6861cc
Compare with similar skills
Second Brain Chat Import next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Second Brain Chat Import this skillundefined-ui/second-brain-os | 999 | — | ~527 | Automated safety check: Pass | MIT | |
| AI Second Braincharlie947/ai-second-brain | 184 | — | ~3.5k | Automated safety check: Pass | MIT | |
| Obsidian Canvas BoardsAgriciDaniel/claude-obsidian | 15k | — | ~1.4k | Automated safety check: Pass | MIT | |
| 3D Brainnateherkai/AIS-OS | 1.6k | — | ~2.1k | Automated safety check: Pass | Custom licence | |
| Icm ArchitectRinDig/icm-architect | 1.8k | — | ~3.2k | Automated safety check: Pass | MIT | |
| Second BrainNicholasSpisak/second-brain | 735 | — | ~1.5k | Automated safety check: Notes | None |
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Related
Works with
Categories
Questions about Second Brain Chat Import
What does Second Brain Chat Import do?
Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first. Second Brain Chat Import is an agent skill from undefined-ui/second-brain-os. Triage an exported chat history into what to ingest, what to archive and what to delete, with a privacy pass first.
When should I use Second Brain Chat Import?
Second Brain Chat Import fits situations like: the user has exported their Claude; chatGPT history; asks to import old conversations; asks what in their chat archive is worth keeping.
How do I install Second Brain Chat Import in Claude Code?
Run `npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a claude-code`. Or copy the skill folder (skills/second-brain-chat-import in undefined-ui/second-brain-os) into .claude/skills/second-brain-chat-import in your project. Claude Code loads it when a task matches its description.
How do I install Second Brain Chat Import in Codex?
Run `npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a codex`. Or copy the skill folder (skills/second-brain-chat-import in undefined-ui/second-brain-os) into .agents/skills/second-brain-chat-import in your project. Codex loads it when a task matches its description.
Can I use Second Brain Chat Import in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add undefined-ui/second-brain-os --skill second-brain-chat-import -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/second-brain-chat-import, .gemini/skills/second-brain-chat-import, .github/skills/second-brain-chat-import and .opencode/skills/second-brain-chat-import in your project.
What does Second Brain Chat Import need to run?
SKILL.md names no scripts, command-line tools or credentials: Second Brain Chat Import is instructions for the agent only.
Does Second Brain Chat Import access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Second Brain Chat Import safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Second Brain Chat Import use?
Second Brain Chat Import is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Second Brain Chat Import use?
About 527 tokens (SKILL.md is roughly 2.1k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Second Brain Chat Import?
Skills that share tags, products or a category with Second Brain Chat Import: AI Second Brain (charlie947/ai-second-brain, 184 stars), Obsidian Canvas Boards (AgriciDaniel/claude-obsidian, 15k stars), 3D Brain (nateherkai/AIS-OS, 1.6k stars) and Icm Architect (RinDig/icm-architect, 1.8k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Second Brain Chat Import?
undefined-ui (a GitHub user) maintains it in undefined-ui/second-brain-os, which has 999 GitHub stars. The repository holds 23 skills in this directory. The repository was last updated on September 29, 2026.
Source: undefined-ui/second-brain-os on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.