viral-ngs: Instructions file for Claude Code

CLAUDE.md

viral-ngs CLAUDE.md is an instructions file for Claude Code from broadinstitute/viral-ngs. It costs 323 tokens per session, scanned A, a copy of viral-ngs copilot-instructions.md, MIT.

Coding instructions for viral-ngs, a Python toolkit for analysing viral genetic-sequencing data, written for Claude Code.

In plain words
What is it for?
Use them when Claude edits viral-ngs documentation or code, runs tests, or works with its bilingual website.
Why use it?
They explain the required container-based tests, dependency setup, language rules, and important project files.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions CLAUDE.md; mentions Claude Code; mentions AGENTS.md.

This is broadinstitute/viral-ngs's own configuration. It tells Claude Code how to work on viral-ngs 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 viral-ngs configures →

Reuse

Borrowing it

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

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 viral-ngs CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/broadinstitute/viral-ngs/claude-md/github.svg)](https://agentmods.dev/instructions/broadinstitute/viral-ngs/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/broadinstitute/viral-ngs/claude-md"><img src="https://agentmods.dev/badge/instructions/broadinstitute/viral-ngs/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for viral-ngs CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/broadinstitute/viral-ngs/claude-md"><img src="https://agentmods.dev/badge/instructions/broadinstitute/viral-ngs/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 323 This file is loaded in full into every session.
When invoked 323 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 92% copy Near-identical to another mod 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 $0.00323 $0.00323
Opus 5 $0.00161 $0.00161
Sonnet 5 $0.00065 $0.00065
Haiku 4.5 $0.00032 $0.00032

Measured 10d ago against content hash b22853cf7ba7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

viral-ngs 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 10d 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.

Origin

This is a copy

92% identical to viral-ngs copilot-instructions.md — 18 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

CLAUDE.md · 33 lines

What it actually says

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

IMPORTANT: Always read AGENTS.md at the start of every session before doing any work. It contains comprehensive project context and development guidelines that are essential for working in this codebase.

Quick Reference

  • Docker-centric development: Run tests inside containers, not on host
  • Import pattern: from viral_ngs import core then core.samtools.SamtoolsTool()
  • Test location: tests/unit/<module>/
  • Dependencies: ALL via conda, not pip (see docker/requirements/*.txt)

Running Tests

docker run --rm \
  -v $(pwd):/opt/viral-ngs/source \
  quay.io/broadinstitute/viral-ngs:main-core \
  pytest -rsxX -n auto /opt/viral-ngs/source/tests/unit

Key Files

File Purpose
AGENTS.md Full AI assistant guidance
pyproject.toml Package configuration
docker/ Dockerfiles and requirements
src/viral_ngs/ Source code
tests/ Test files
.agents/skills/ Reusable agent playbooks and scripts
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. 10d ago First seen · 33 lines · 323 tokens per session scan A b22853cf7ba7

Subscribe to this mod's changes

viral-ngs CLAUDE.md is an instructions file published in the GitHub repository broadinstitute/viral-ngs (197 stars, last pushed 7d ago), licensed MIT. It adds 323 tokens to every session, about $0.0016 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to viral-ngs copilot-instructions.md, differing in 18 lines, and is treated as a copy.

Related

Other instructions, from other repositories

next.js AGENTS.md

AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

vercel/next.js · 7,296 tokens

codex AGENTS.md

AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

openai/codex · 5,153 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens

vscode oss-third-party-notices.instructions.md

Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).

microsoft/vscode · 5,001 tokens

langchain AGENTS.md

AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.

langchain-ai/langchain · 4,469 tokens