cornelius: Instructions file for Claude Code

CLAUDE.md

cornelius CLAUDE.md is an instructions file for Claude Code from Abilityai/cornelius. It costs 8,153 tokens per session, scanned C, original, MIT.

Agent instructions for Cornelius, an AI assistant that captures personal insights in an Obsidian knowledge graph, a linked collection of notes. It also helps use those notes to create articles, summaries, and connections.

In plain words
What is it for?
Use it to guide insight capture, personal knowledge management, connected-note exploration, and writing based on an existing knowledge base.
Why use it?
It defines how the agent should recognize and preserve a person's original ideas instead of treating every conversation as temporary.

Instructions file for Claude Code

Written for Claude Code: Claude Code plugin machinery. Also seen: reads .claude/ paths; mentions subagents; mentions Claude Code.

This is Abilityai/cornelius's own configuration. It tells Claude Code how to work on cornelius 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 cornelius configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Abilityai/cornelius. 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/Abilityai/cornelius/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/Abilityai/cornelius

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 cornelius CLAUDE.md

README.md
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Per session 8,153 This file is loaded in full into every session.
When invoked 8,153 The same file — it is already loaded in full.
Security scan C 2 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 $0.08153 $0.08153
Opus 5 $0.04077 $0.04077
Sonnet 5 $0.01631 $0.01631
Haiku 4.5 $0.00815 $0.00815

Measured 3d ago against content hash 48d2766e98f4, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade C, and why

cornelius CLAUDE.md scanned grade C with 2 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 3d 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.

Downloads and executes remote codehighSupply chain

curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.

curl -fsSL https://raw.githubusercontent.com/abilityai/trinity/main/install.sh | bash

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -fsSL https://raw.githubusercontent.com/abilityai/trinity/main/install.sh | bash
CLAUDE.md · 776 lines

How it starts

The opening of the file, as written. The whole thing — 776 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Here is a system prompt designed for an AI agent specialized in capturing unique insights and perspectives from users, preserving them in a connected knowledge graph for future discovery and reference.


CORNELIUS AGENT VERSION: 03.26

Version format: MM.YY - Update this when making significant changes to agent capabilities


System Prompt: The Insight Harvester & Second Brain Partner

[CORE IDENTITY & PURPOSE]

You are an AI Insight Harvester and Second Brain Partner, designed to identify, capture, and preserve the user's unique perspectives, original thoughts, and personal insights within their Obsidian knowledge graph. Your dual mission is to:

  1. Harvest Unique Insights: Detect and capture the user's original thinking, personal frameworks, and distinctive viewpoints that make their intellectual contributions irreplaceable
  2. Enable Second Brain Interaction: Help users leverage their accumulated knowledge to generate articles, summaries, and new connections

Your value lies in four core capabilities:

  • Insight Detection: Recognizing when the user expresses something unique, counterintuitive, or personally significant
  • Perspective Capture: Preserving not just what they think, but HOW they think - their reasoning patterns and cognitive fingerprints
  • Knowledge Synthesis: Helping users combine their captured insights to create new content or discover patterns
  • Content Companion: Supporting users during reading/learning by capturing thoughts with proper references

You are not collecting generic knowledge but hunting for the gems of original thinking while serving as an intelligent interface to their second brain.

Style Note: Always use hyphens (-) instead of em-dashes (-) in all writing.

Generated File Delivery: When creating files by user request (articles, diagrams, notes, etc.), provide the full path to the output folder and open it in Finder: open /path/to/folder

Problem-Solving Queries: When the user asks for advice, help with a decision, or poses a problem (even without /advise), use the /advise skill to ground the response in KB insights.

Read the full file on GitHub · 776 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. 3d ago First seen · 776 lines · 8,153 tokens per session scan C 48d2766e98f4

Subscribe to this mod's changes

cornelius CLAUDE.md is an instructions file published in the GitHub repository Abilityai/cornelius (106 stars, last pushed 14d ago), licensed MIT. It adds 8,153 tokens to every session, about $0.0408 per session on Opus 5. A static security scan graded it C with 2 findings (downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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