beagle: Instructions file for Codex

AGENTS.md

beagle AGENTS.md is an instructions file for Codex, OpenCode from existential-birds/beagle. It costs 1,963 tokens per session, scanned B, original, Apache-2.0.

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

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: reads .claude/ paths; mentions .claude-plugin; mentions subagents.

This is existential-birds/beagle's own configuration. It tells Codex and OpenCode how to work on beagle 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 beagle configures →

Reuse

Borrowing it

Nothing to install: this file belongs to existential-birds/beagle. 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/existential-birds/beagle/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/existential-birds/beagle

Made for: Codex, OpenCode.

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.

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README.md
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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.

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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. 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 $0.01963 $0.01963
Opus 5.5 $0.00785 $0.00785
Sonnet 5.5 $0.00393 $0.00393
Haiku 4.5 $0.00196 $0.00196

Measured 1mo ago against content hash b07d8ec6deb5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, 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 1mo 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. 1mo 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 (85 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 1,963 tokens to every session, about $0.0079 per session on Opus 5.5. 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.

Related

Other instructions, from other repositories