open-second-brain SKILL.md skillA
This file is byte-identical to the first copy the registry indexed. Same content hash, so the same checks give both the same grade.
open-second-brain from itechmeat/open-second-brain is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add itechmeat/open-second-brain/open-second-brain@git:20260928.3e59f31Pins git:20260928.3e59f31 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- itechmeat/open-second-brain
- Path
plugins/codex/skills/open-second-brain/SKILL.md- Versions recorded
- 2
- Latest version
- git:20260928.3e59f31, committed Sep 28, 2026
- First version recorded
- Sep 25, 2026
- Size
- 4,937 bytes
- Repository stars
- 492
- License
- MIT
Use Open Second Brain to read, write, and maintain an agent-owned second brain in an Obsidian-compatible Markdown vault. The agent owns one top-level directory (`Brain/`). User-authored notes live wherever the operator names them and are read-only inputs when listed in `notes.read_paths`.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Open Second Brain Use this skill when a user asks an agent to use, configure, inspect, or maintain Open Second Brain. ## Layout Open Second Brain owns one top-level directory in the vault: `Brain/`. Everything the agent generates on its own lives under it. The exception is the note-lifecycle family (`brain_note_lifecycle`, `brain_scaffold_stub`), which acts on a user-note path the caller names and can move a note to a second top-level directory, `Archive/`. - **`Brain/`** - agent-writable observing memory. Taste signals, accreted preferences (unconfirmed → confirmed → retired), evidence log, snapshots. Operations go through MCP tools `brain_feedback`, `brain_apply_evidence`, `brain_dream`, `brain_brief`, `brain_query`, `brain_doctor` - see the `brain-memory` skill for the calling protocol. CLI counterparts: `o2b brain *`. - **User-authored notes** - the operator's daily journal, weekly notes, project notes, etc. Folder names are operator-chosen. The agent reads these paths only when they appear under `notes.read_paths` in `Brain/_brain.yaml`; the agent never writes to them. ## Core principles - Treat the vault as user-owned durable knowledge. …
Read the whole file at its exact version.
How to install
mdr add itechmeat/open-second-brain/open-second-brain@sha256:8c13198762fc0489The line at the top of this page pins the label git:20260928.3e59f31, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_ygxz3oqck7olms6x)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Sep 25, 2026 and Sep 28, 2026, about one every 3 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260928.3e59f31 latest | 2026-09-28 | 3e59f31 | 4,937 B | A | view · diff |
| git:20260925.a4d3ecf | 2026-09-25 | a4d3ecf | 3,907 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (4937 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
itechmeat/open-second-brain · 492 stars · license MIT · pushed 2026-10-22 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_ygxz3oqck7olms6x GET https://markdownregistry.com/api/v1/resolve?ref=itechmeat/open-second-brain/open-second-brain GET https://markdownregistry.com/api/v1/blob/8c13198762fc04894e6448d04220f835607d9cea33ae00678994e6786d287d30
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.
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