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.
npx agentmods add instructions/the-sid-dani/second-brain-os/claude-mdgit clone --depth 1 https://github.com/the-sid-dani/second-brain-osWrote 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/instructions/the-sid-dani/second-brain-os/claude-md)<a href="https://agentmods.dev/instructions/the-sid-dani/second-brain-os/claude-md"><img src="https://agentmods.dev/badge/instructions/the-sid-dani/second-brain-os/claude-md.svg" alt="Measured on agentmods" 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 | $0.03397 | $0.03397 |
| Opus 5 | $0.01699 | $0.01699 |
| Sonnet 5 | $0.00679 | $0.00679 |
| Haiku 4.5 | $0.00340 | $0.00340 |
Grade A, and why
second-brain-os CLAUDE.md 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 4d 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 — 192 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Second-Brain OS — Project Instructions for <assistant.name>
This file is project-scoped instructions only. Persona, user, and tooling context live in dedicated files — do not duplicate them here.
Load Order at Session Start
- @SOUL.md — <assistant.name>'s persona, voice, boundaries
- @USER.md — <user.name>'s profile, role, communication preferences, team
- @IDENTITY.md — <assistant.name>'s name, version, origin
- @TOOLS.md — Available tools and capabilities
- @README.md — Project map and update rules
If anything below conflicts with those files, those files win.
Configuration — source of truth for skills
Skills (/new-project, /archive-project, /prune-projects, the intent-detector hook) read the values below as the source of truth. To fork this workspace for your own use, run /bootstrap — it walks through these values interactively and rewrites this section. Every skill references these paths and identity values symbolically (e.g., <workspace.projects>) and adapts automatically.
workspace
workspace.root=<workspace.root>(default:workspace; rename toworkspace,brain,<assistant>-workspace, etc.)workspace.inbox=0-Inboxworkspace.projects=1-Projectsworkspace.areas=2-Areas— evergreen HQ workstations (PARA Areas); starts empty, populate as you grow recurring workstreams (see HQ model below)workspace.coding=3-Codingworkspace.resources=4-Resourcesworkspace.archive=5-Archive
Resolved paths (combine the above): <workspace.root>/<workspace.projects> → e.g., workspace/1-Projects.
templates (under <workspace.root>/<workspace.resources>/templates/)
templates.project_claude=project-claude-template.md— for non-code project CLAUDE.mdtemplates.project_memory=project-memory-template.md— for any project's memory.mdtemplates.code_claude=code-project-claude-template.md— for code-repo project CLAUDE.mdtemplates.persona=persona/— for persona file templates (used by/bootstrap)
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.
- 4d ago First seen · 192 lines · 3,397 tokens per session scan A 8c1a2be27ee4
second-brain-os CLAUDE.md is an instructions file published in the GitHub repository the-sid-dani/second-brain-os (2 stars, last pushed 29d ago), licensed MIT. It adds 3,397 tokens to every session, about $0.0170 per session on Opus 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.
Other instructions, from other repositories
vault-operator AGENTS.md
AGENTS.md instructions for pssah4/vault-operator, covering vault operator, projekt-regeln, navigation, zuerst lesen, projekt, tech stack and build und deploy.
Kompl AGENTS.md
Instructions for tuirk/Kompl, covering agents.md — kompl operator guide, what is kompl?, agent rules — wiki safety (read before any docker command), never without explicit user confirmation and if a destructive action is going to happen anyway.
llm-brain CLAUDE.md
Instructions for kimsanguine/llm-brain, covering llm-brain — claude code 운영 지침, 가드레일 (절대 위반 금지), 프라이버시 경계 (agent memory os), 명령어 and ingest.
second-brain-starter-kit AGENTS.md
AGENTS.md instructions for tonydzi/second-brain-starter-kit, covering agents.md — working in this repo, what this repo is, layout, how to verify a change and conventions.
memex CLAUDE.md
Claude Code instructions for evan-moon/memex, covering memex, memex, architecture, working on the ui and who this is for.
thebrain-mcp CLAUDE.md
Instructions for yBookoff/thebrain-mcp, covering thebrain-mcp — working notes for claude, invariants, layout, api gotchas that keep biting and semantic layer.