obsidian-second-brain turns an Obsidian vault into persistent, searchable memory for Claude Code and other command-line coding agents, storing knowledge as linked Markdown notes. It is for developers, founders, writers, and researchers who want agents to retain project context across sessions. Its catalogue entries provide commands, hooks, a plugin, a skill, and instructions for capturing, finding, and maintaining that memory.
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.
git clone --depth 1 https://github.com/eugeniughelbur/obsidian-second-brainWrote 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.
[](https://agentmods.dev/commands/eugeniughelbur/obsidian-second-brain/crew)<a href="https://agentmods.dev/commands/eugeniughelbur/obsidian-second-brain/crew"><img src="https://agentmods.dev/badge/commands/eugeniughelbur/obsidian-second-brain/crew/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.
<a href="https://agentmods.dev/commands/eugeniughelbur/obsidian-second-brain/crew"><img src="https://agentmods.dev/badge/commands/eugeniughelbur/obsidian-second-brain/crew.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00019 | $0.01141 |
| Opus 5.5 | $0.00008 | $0.00456 |
| Sonnet 5.5 | $0.00004 | $0.00228 |
| Haiku 4.5 | $0.00002 | $0.00114 |
Grade A, and why
crew 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 6d 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.
How it starts
The opening of the file, as written. The whole thing — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Crew
Crew gives 4 agents one logbook without Obsidian. Run its Python helper directly; Python 3.10 or later is the only dependency.
Resolve SKILL_ROOT from the installed skill location, then use SKILL_ROOT/scripts/crew.py.
For a source checkout, the helper is scripts/crew.py.
Never install packages to run Crew.
Setup
-
Ask whether the user wants a plain folder or an Obsidian vault. Use their stated choice if already supplied.
-
For a plain folder, suggest
~/crew. For a known vault, suggestwiki/team/inside it. -
Run one command with the chosen absolute path:
python3 "SKILL_ROOT/scripts/crew.py" --dir "/path/to/crew" setup # Or, for an existing vault: python3 "SKILL_ROOT/scripts/crew.py" setup --vault "/path/to/vault" -
Report the configured agents. Setup detects CLI executables or config folders;
--agents claude codex cursorselects them explicitly. -
Show the printed Grok Bot profile block. Its runner must reach the same folder through an existing connection or shared mount.
-
Tell Codex users to run
/hooksto trust Crew. Until trusted, the hooks inject nothing. -
Restart the configured agents. Record one test job, then ask each other agent what happened.
Setup merges existing hook arrays and replaces only Crew's marked rules sections.
Existing prototype hooks remain registered. Switching from a prototype requires explicit user approval to remove its old entries.
Grok Bot has no hooks. Crew prints its profile text for the user to paste. No background loop, scheduler, remote connection, or message sender is installed.
Record jobs and lessons
After each completed job, add one factual line with a count and evidence:
python3 "SKILL_ROOT/scripts/crew.py" add --agent codex --area side --did "Fixed 2 tests" --where "tests/test_app.py"
python3 "SKILL_ROOT/scripts/crew.py" lesson --from codex --for claude --kind gap --text "Cover empty input" --evidence "tests/test_app.py"
Valid agents are claude, codex, cursor, and grokbot. Lessons can target all.
Keep secrets out of records. Use an actual file path or source URL for evidence.
For vault storage, follow references/ai-first-rules.md, including its Crew record schema.
If that reference path fails, search upward for the installed spec and say so before writing if it remains unavailable.
Use existing [[wikilinks]] when naming vault entities. Crew preserves them and source URLs.
The helper writes type: crew-log and type: crew-lessons notes with frontmatter and a retrieval preamble.
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.
- 6d ago First seen · 92 lines · 19 tokens per session scan A 16981c336d6b
crew is a command published in the GitHub repository eugeniughelbur/obsidian-second-brain (4,858 stars, last pushed 2d ago), licensed MIT. It adds 19 tokens to every session and 1,141 once invoked, about $0.0001 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 2026-10-17.
Other commands, from other repositories
second-brain-mapping
Map your vault: extract structured metadata from every typed file, surface cross-doc insights, optionally build a knowledge graph.
cierre
A sales call just ended: turn its transcript into the full follow-up (CRM, tasks, email draft, reminder, coaching).
daily-journal
Daily journal interview and entry creator with emotional floor tagging.
deconstruct
First-principles analyst: surface hidden assumptions, find foundational truths, rebuild from scratch.
diagnose
Run a self-check on your AI Brain Starter install (CLAUDE.md, Meta folder, skills, hooks, MCPs).
evolve
Cluster hardened instincts into a proposed Command / Skill / Agent (Instinct Engine).