hippocampus: Instructions file for Claude Code

CLAUDE.md

hippocampus CLAUDE.md is an instructions file for Claude Code from sturlese/hippocampus. It costs 1,570 tokens per session, scanned A, original, MIT.

Project instructions for Hippocampus, an Obsidian vault and Git repository that organizes messy notes into a cross-linked knowledge base. They describe its folders, page format, links, and rules for recording changes.

In plain words
What is it for?
Use them when processing inbox notes, creating or renaming wiki pages, updating the index or logs, resolving contradictions, or answering questions from the vault.
Why use it?
They provide the detailed rules needed to keep notes searchable, traceable, and consistent across the vault.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions Claude Code.

This is sturlese/hippocampus's own configuration. It tells Claude Code how to work on hippocampus itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything hippocampus configures →

Reuse

Borrowing it

Nothing to install: this file belongs to sturlese/hippocampus. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/sturlese/hippocampus/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/sturlese/hippocampus

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 hippocampus CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/sturlese/hippocampus/claude-md.svg)](https://agentmods.dev/instructions/sturlese/hippocampus/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/sturlese/hippocampus/claude-md"><img src="https://agentmods.dev/badge/instructions/sturlese/hippocampus/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,570 This file is loaded in full into every session.
When invoked 1,570 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.01570 $0.01570
Opus 5 $0.00785 $0.00785
Sonnet 5 $0.00314 $0.00314
Haiku 4.5 $0.00157 $0.00157

Measured 6d ago against content hash 9fd114081a96, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

hippocampus 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 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.

CLAUDE.md · 107 lines

How it starts

The opening of the file, as written. The whole thing — 107 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Hippocampus — a Claude Code–native Obsidian vault with Codex support

This directory is three things at once: a git repository, a Claude Code project, and an Obsidian vault. The user drops messy notes into inbox/; the agent turns them into a structured, cross-linked knowledge base under wiki/. Obsidian is for browsing; Claude Code is the native interface and Codex is supported through its AGENTS.md and skill adapters. This file is the canonical project contract for both agents.

Layout

inbox/          Messy source notes, any format/language. IMMUTABLE: read, never edit.
inbox/_done/    Processed inbox files are MOVED here by the ingest skill (provenance).
wiki/           The structured knowledge base. Everything the agent writes lives here.
├── index.md    Master catalog: one line per page. Update on every page create/rename.
├── log.md      Append-only operations journal. New entries at the TOP. Never edit past entries.
├── hot.md      Recent-context cache, ≤500 words. Overwrite completely each refresh.
├── sources/    One page per ingested source (type: source)
├── concepts/   Ideas, patterns, frameworks (type: concept)
├── entities/   People, orgs, products, tools (type: entity)
├── projects/   Ongoing personal/work projects (type: project)
├── notes/      Synthesis, decisions, saved sessions (type: note)
└── meta/       Lint reports, dashboards (type: meta)
_templates/     Canonical skeletons per note type. THE source of truth for page structure.
_attachments/   Images/PDFs referenced by wiki pages.
docs/           Framework documentation (upstream, part of the template). NOT vault content — never file notes here.

Frontmatter schema

Flat YAML only (no nested objects — Obsidian Properties requires flat). Universal fields, every page:

---
type: source | entity | concept | project | note | meta
title: "Human-Readable Title"
created: YYYY-MM-DD
updated: YYYY-MM-DD          # bump on every content edit
tags: [lowercase, hierarchical/ok]
status: seed | developing | mature | evergreen
related: ["[[Other Page]]"]  # wikilinks in YAML must be quoted
sources: ["[[Source Page]]"]
---

Read the full file on GitHub · 107 lines

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. 6d ago First seen · 107 lines · 1,570 tokens per session scan A 9fd114081a96

Subscribe to this mod's changes

hippocampus CLAUDE.md is an instructions file published in the GitHub repository sturlese/hippocampus (28 stars, last pushed 16d ago), licensed MIT. It adds 1,570 tokens to every session, about $0.0078 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 2026-08-30.

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