beagle AGENTS.md

Project instructions for Beagle, a marketplace of Claude Code add-ons for code review and development workflows. They describe its repository layout, included add-on groups, and local development setup.

In plain words
What is it for?
Use them when developing or maintaining Beagle, its marketplace manifest, its add-on groups, or its local Claude Code settings.
Why use it?
They give coding agents the project-specific context needed to make changes in the right folders and follow the repository's conventions.

Instructions file for CodexOpenCode

Install

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.

agentmods
npx agentmods add instructions/existential-birds/beagle/agents-md
Clone the repo
git clone --depth 1 https://github.com/existential-birds/beagle

Made for: Codex, OpenCode.

Per session 1,963 This file is loaded in full into every session.
When invoked 1,963 The same file — it is already loaded in full.
Security scan B 1 finding. 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 $0.01963 $0.01963
Opus 5 $0.00981 $0.00981
Sonnet 5 $0.00393 $0.00393
Haiku 4.5 $0.00196 $0.00196

Measured 2d ago against content hash b07d8ec6deb5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

beagle AGENTS.md scanned grade B with 1 finding 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 2d 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.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

# In Claude Code settings (~/.claude/settings.json)
Origin

Copies of this mod

1 near-identical copy found in the catalogue:

AGENTS.md · 130 lines

How it starts

The opening of the file, as written. The whole thing — 130 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

This file provides guidance to Codex when working with code in this repository.

What This Is

Beagle is a Claude Code plugin marketplace providing framework-aware code review skills and verification workflows for pre-push reviews and GitHub bot feedback handling. It contains 10 focused plugins with 132 skills.

Marketplace Architecture

beagle/
├── .claude-plugin/
│   └── marketplace.json         # Marketplace manifest (10 plugins)
└── plugins/
    ├── beagle-core/             # Shared workflows, verification, git workflows, skill tooling (19 skills)
    ├── beagle-python/           # Python, FastAPI, SQLAlchemy, PostgreSQL, pytest (7 skills)
    ├── beagle-go/               # Go, BubbleTea, Wish SSH, Prometheus (13 skills)
    ├── beagle-elixir/           # Elixir, Phoenix, LiveView, ExUnit, ExDoc (11 skills)
    ├── beagle-ios/              # Swift, SwiftUI, SwiftData, iOS frameworks (16 skills)
    ├── beagle-react/            # React, React Flow, shadcn/ui, Tailwind, Vitest, Remix v2 (28 skills)
    ├── beagle-rust/             # Rust, tokio, axum, sqlx, serde (12 skills)
    ├── beagle-ai/               # Pydantic AI, LangGraph, DeepAgents, Vercel AI SDK (deprecated)
    ├── beagle-docs/             # Documentation quality, AI writing detection (10 skills)
    ├── beagle-analysis/         # Brainstorming, ADRs, strategy, LLM-as-judge, spec resolution, PRFAQ filter (14 skills)
    └── beagle-testing/          # Test plan generation and execution (2 skills)

Each active plugin is a directory under plugins/ with its own README.md and skills/ directory. The marketplace manifest at .claude-plugin/marketplace.json is the only plugin manifest; individual plugin directories do not have plugin.json files.

Local Development

Test the marketplace during development:

# In Claude Code settings (~/.claude/settings.json)
{
  "plugins": ["/path/to/your/beagle"]
}

Restart Claude Code after changes to reload. Skills are discovered from plugin skills/ directories and trigger keywords in skill frontmatter. Codex users can install the same skills by linking active skill directories into ~/.agents/skills/ (see .codex/INSTALL.md).

Read the full file on GitHub · 130 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. 2d ago First seen · 130 lines · 1,963 tokens per session scan B b07d8ec6deb5

Subscribe to this mod's changes

beagle AGENTS.md is an instructions file published in the GitHub repository existential-birds/beagle (79 stars, last pushed 23d ago), licensed Apache-2.0. It adds 1,963 tokens to every session, about $0.0098 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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