Borrowing it
Nothing to install: this file belongs to stefanhoelzl/codehydra. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/stefanhoelzl/codehydra/main/CLAUDE.mdgit clone --depth 1 https://github.com/stefanhoelzl/codehydraWrote 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/stefanhoelzl/codehydra/claude-md)<a href="https://agentmods.dev/instructions/stefanhoelzl/codehydra/claude-md"><img src="https://agentmods.dev/badge/instructions/stefanhoelzl/codehydra/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 5.1 | $0.07616 | $0.07616 |
| Opus 5 | $0.03808 | $0.03808 |
| Sonnet 5 | $0.01523 | $0.01523 |
| Haiku 4.5 | $0.00762 | $0.00762 |
Grade A, and why
codehydra 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 7d 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 — 401 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code when working with this repository.
CRITICAL RULES
These rules MUST be followed. Violations require explicit user approval.
No Ignore Comments
NEVER add without explicit user approval:
// @ts-ignore,// @ts-expect-error,// eslint-disable*,anytype assertions- Modifications to
.eslintignore,.prettierignore
API/IPC Interface Changes
NEVER modify without explicit user approval:
- IPC channel names/signatures (
api:project:*,api:workspace:*) - Intent/event type definitions, operation interfaces
- Preload script exposed APIs, event names/payloads, shared types in
src/shared/
Why: IPC contracts affect main/renderer sync, type safety, and backwards compatibility.
New Boundary Interfaces
NEVER add without explicit user approval:
- New abstraction interfaces (
*Layer,*Client,*Provider) - New boundary types (I/O, network, filesystem, process abstractions)
- Entries to External System Access Rules table
Why: Architectural decisions with maintenance burden. Must follow established patterns.
External System Access Rules
All external access MUST use abstraction interfaces:
| External System | Required Interface | Forbidden Direct Access |
|---|---|---|
| Filesystem | FileSystemBoundary |
node:fs/promises |
| HTTP requests | HttpClient |
fetch() |
| Port operations | PortManager |
net module |
| Process spawning | ProcessRunner |
execa |
| Agent operations | AgentProvider, AgentServerManager |
Direct OpenCode SDK |
| OpenCode API | SdkClientFactory |
Direct HTTP/SSE |
| Git operations | IGitClient |
simple-git |
| Electron Window | WindowBoundary |
BaseWindow |
| Electron View | ViewBoundary |
WebContentsView |
| Electron Session | SessionBoundary |
session |
| Electron IPC | IpcBoundary |
ipcMain |
| Electron Dialog | DialogBoundary |
dialog |
| Electron Image | ImageBoundary |
nativeImage |
| Electron App | AppBoundary |
app |
| Electron Power | AppBoundary.allowPowerSaving |
powerSaveBlocker |
| Electron Menu | MenuBoundary |
Menu |
| Electron Notification | OsNotificationBoundary |
Notification |
| PostHog telemetry | PostHogBoundary |
posthog-node |
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.
- 7d ago First seen · 401 lines · 7,616 tokens per session scan A 58a69c0f63b6
codehydra CLAUDE.md is an instructions file published in the GitHub repository stefanhoelzl/codehydra (20 stars, last pushed 8d ago), licensed MIT. It adds 7,616 tokens to every session, about $0.0381 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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