Borrowing it
Nothing to install: this file belongs to fortrabbit/agent-skills. 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/fortrabbit/agent-skills/main/AGENTS.mdgit clone --depth 1 https://github.com/fortrabbit/agent-skillsWrote 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/fortrabbit/agent-skills/agents-md)<a href="https://agentmods.dev/instructions/fortrabbit/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/fortrabbit/agent-skills/agents-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.
<a href="https://agentmods.dev/instructions/fortrabbit/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/fortrabbit/agent-skills/agents-md.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00686 | $0.00686 |
| Opus 5.5 | $0.00274 | $0.00274 |
| Sonnet 5.5 | $0.00137 | $0.00137 |
| Haiku 4.5 | $0.00069 | $0.00069 |
Grade A, and why
agent-skills AGENTS.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 today.
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 — 35 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Guidance for coding agents working on this repository.
What this is
One agent skill, skills/fortrabbit/, in the open Agent Skills format. No build step for the skill; .github/scripts/build-openai-zip.sh only packages it for the OpenAI directory. The frbit CLI (frbit skills install), gh skill and npx skills install it from the GitHub release.
skills/fortrabbit/
├── SKILL.md always loaded when the skill triggers: tool routing, finding the environment, safety
├── references/ one file per task, loaded on demand, one level deep
└── scripts/ deterministic helpers the skill runs (database over SSH)
Rules
SKILL.mdstays short (under 150 lines). Detail goes into a reference; every reference is linked from the table inSKILL.md.- Frontmatter: only the spec fields
name,description,license,compatibility,metadata. Other fields break uploads to claude.ai and the Skills API. - Facts come from the platform, not from memory: MCP tools from
fortrabbit/frapi(src/Module/Mcp), CLI commands fromfortrabbit/frbit-cli, templates fromfortrabbit/specs, everything else from docs.fortrabbit.com. Link to docs rather than copying long passages. - No project config file: the environment is found from the git remote through MCP or the CLI.
- Never instruct the agent to ask for, print or store a password or token.
- Scripts: POSIX-friendly bash,
set -euo pipefail, validate arguments, passshellcheck. install.shat the root is a stub that only prints how to update: 1.x installs fetch it frommainwhen they update themselves. Keep it, and keep it installing nothing.
Releases
VERSION holds the version; metadata.version in SKILL.md and version in .claude-plugin/plugin.json and .codex-plugin/plugin.json must match it. .github/scripts/check-manifests.sh checks that and the OpenAI listing limits, also in CI. Run claude plugin validate . after changing a manifest. A push to main that changes VERSION tags and publishes a GitHub release (.github/workflows/release.yml) with the OpenAI upload ZIP attached. The CLI checks that VERSION in the archive matches the release tag.
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.
- today Changed · +2 lines · +150 tokens per session d498a3486150
- 3d ago Changed · -56 lines · -714 tokens per session 72d1ce67f2d4
- 7d ago Changed bc9479b94c8a
- 1mo ago Changed · +31 lines · +645 tokens per session 2091e9e4a62d
- 2mo ago First seen · 58 lines · 605 tokens per session scan A 26953625e303
agent-skills AGENTS.md is an instructions file published in the GitHub repository fortrabbit/agent-skills (4 stars, last pushed yesterday), licensed MIT. It adds 686 tokens to every session, about $0.0027 per session on Opus 5.5. 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 2026-08-31.
Other instructions, from other repositories
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).
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.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
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.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.