brain

brain is a skill for Claude Code from jzhao234/big-brain. It costs 87 tokens per session (536 once invoked), scanned A, original, MIT.

A guide for orienting an agent in the user's second brain: a personal vault of notes about projects, tasks, and ideas.

In plain words
What is it for?
Use it at the start of ongoing work, or when asking what is being worked on, what is overdue, what is due soon, or what tasks are open.
Why use it?
It gives the agent current context about active work, deadlines, inbox items, and project history instead of making it reconstruct that context from scratch.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter.

Good fit Use it at the start of ongoing work, or when asking what is being worked on, what is overdue, what is due soon, or what tasks are open.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/jzhao234/big-brain/brain
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add jzhao234/big-brain --skill brain
Clone the repo
git clone --depth 1 https://github.com/jzhao234/big-brain

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for brain

README.md
[![agentmods](https://agentmods.dev/badge/skills/jzhao234/big-brain/brain/github.svg)](https://agentmods.dev/skills/jzhao234/big-brain/brain)
Your own site
<a href="https://agentmods.dev/skills/jzhao234/big-brain/brain"><img src="https://agentmods.dev/badge/skills/jzhao234/big-brain/brain/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for brain

Your own site · 80×15
<a href="https://agentmods.dev/skills/jzhao234/big-brain/brain"><img src="https://agentmods.dev/badge/skills/jzhao234/big-brain/brain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 87 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 536 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00087 $0.00536
Opus 5.5 $0.00035 $0.00214
Sonnet 5.5 $0.00017 $0.00107
Haiku 4.5 $0.00009 $0.00054

Measured 7d ago against content hash 08eceb387501, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

brain scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/claude/brain/SKILL.md · 36 lines

What it actually says

brain

The big-brain vault is the user's external memory, shared by all their AI tools. This skill loads it and switches you into brain-aware mode. The vault is whichever one big-brain resolves using the BIG_BRAIN_VAULT env var, a --vault path, or the nearest brain.config.json. Use the big-brain CLI or the big-brain MCP tools; don't hardcode a vault path.

With no argument

  1. Run big-brain status (or call the brain_overview MCP tool).
  2. Report in one screen, BLUF: active projects with their next task, anything overdue or due this week, inbox count if it's piling up. No filler; skip empty sections.
  3. If the vault hasn't been linted recently, run big-brain doctor and surface only warnings.

With an argument

Treat it as a project or topic: big-brain show <arg> (falling back to big-brain search <arg>), then summarize where it stands (goal, status, open tasks, last Log entries) and ask what to work on.

Brain-aware mode (rest of the session)

From here on, keep the vault current as a side effect of the work:

  • Decisions, progress, and problems → big-brain daily --log "..." and a Log line on the affected project.
  • New commitments → project notes; new action items → big-brain task add.
  • Completed work → big-brain task done <id>.
  • Facts worth keeping with no obvious home → big-brain capture "...".

Do routine captures/logs without asking (mention them in one line); ask before rewriting or archiving existing notes. If the vault has git auto-commit enabled, these saves also commit and push on their own. At the end of a work session, make sure what happened is reflected in the vault. The next session (or another LLM) starts from there.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 7d ago Changed 08eceb387501
  2. 1mo ago First seen · 36 lines · 87 tokens per session scan A ae34bb3ff01f

Subscribe to this mod's changes

brain is a skill published in the GitHub repository jzhao234/big-brain (1 stars, last pushed 6d ago), licensed MIT. It adds 87 tokens to every session and 536 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

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wrap-session-up

End-of-session review for a Claude Code conversation. Replays what was discussed, checks for open action items, documents relevant outcomes in the brain vault, and creates Todoist tasks for anything untracked. Use at the end of a work session to ensure nothing falls through the cracks.

michaeljauk/brain-starter · 60 tokens

vault-onboarding-guide

An interactive guide for learning a file-based knowledge store with an agent. It teaches how to organize incoming material, projects, plans, tasks, logs, parked work, and resumed work.

dzhokhov/markdown-agent-vault-ru · 187 tokens

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Bootstrap an Obsidian vault with the AI Pro Obsidian Plugin. Creates the complete vault structure, system files, Obsidian configuration, memory system, hooks, and output styles, then runs personalized onboarding to tailor the workspace to the user. Uses a single universal structure with no mode selection. Trigger when…

anliberant/obsidian-ai-setup · 94 tokens

molio-kb

Query the user's local Molio knowledge base — browse files, full-text search, read documents, and run AI Q&A grounded in the user's own notes (read-only).

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priority-dashboard

Use this to rebuild, inspect, or temporarily steer {{username}}'s current PersonalOS priority dashboard from canonical Actions, Attention Triggers, and owner context. Do NOT use it to create, complete, or independently manage tasks; use task-manager for Action and Trigger lifecycle changes.

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Query the user's local and synced-device data via the screenpipe REST API at localhost:3030 — recordings, audio, UI, meetings, connected services, and memory. Use for screen activity, other-device or cross-device history, productivity, media export, connections, durable memory, or discovering and automating saved…

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