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.
npx agentmods add instructions/youdotcom-oss/agent-skills/agents-mdgit clone --depth 1 https://github.com/youdotcom-oss/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/youdotcom-oss/agent-skills/agents-md)<a href="https://agentmods.dev/instructions/youdotcom-oss/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/youdotcom-oss/agent-skills/agents-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 | $0.01092 | $0.01092 |
| Opus 5 | $0.00546 | $0.00546 |
| Sonnet 5 | $0.00218 | $0.00218 |
| Haiku 4.5 | $0.00109 | $0.00109 |
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 5d 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 — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agent Instructions
This repo packages You.com skills and plugin manifests for multiple coding-agent surfaces. Keep changes small, verified, and tied to the requested surface.
Tooling discovery
- Prefer Bun for TypeScript, scripts, orchestration, and running checks. Use Bun to trigger Python and TypeScript tooling unless an existing script says otherwise.
- Bun MCP docs: https://bun.com/docs/mcp
- Before choosing commands, scan
package.json,biome.json,ruff.toml, and relevantpackages/*/package.jsonscripts. Do not guess command names. - Root checks currently flow through Bun:
bun test,bun run check,bun run check:types,bun run check:ts,bun run check:py,bun run check:package. - Package checks often differ. Use the package script in
packages/<name>/package.jsonfor package-scoped work.
Minimal-implementation directive
Before writing code, resolve the task at the FIRST step that holds:
- Does this capability need to exist for the stated task? If it is speculative, do not build it. Say so in one sentence and stop.
- Does something already in THIS codebase do it? Reuse it. Read before you write; re-implementing a helper that lives three files over is the most common waste.
- Does the standard library or the runtime/platform already do it? (
<input type="date">, a DB unique constraint, a CSS rule.) Use it. - Does an already-installed dependency do it? Use it. Do not add a new dependency for something a few lines cover.
- Can it be one clear expression? Write the one expression.
- Otherwise: the smallest code that fully handles the task.
NON-NEGOTIABLE FLOOR: none of the steps above may remove any of these, and "minimal" is never a reason to drop them:
- input validation at trust boundaries (anything crossing a process, network, file, or user edge),
- error handling that prevents data loss or silent corruption,
- authn/authz and other security checks,
- accessibility for anything a human interacts with.
If a step would require cutting one of these, that step does not apply.
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.
- 5d ago First seen · 70 lines · 1,092 tokens per session scan A 3d67329f50ab
agent-skills AGENTS.md is an instructions file published in the GitHub repository youdotcom-oss/agent-skills (66 stars, last pushed 4d ago), licensed MIT. It adds 1,092 tokens to every session, about $0.0055 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.
Other instructions, from other repositories
Unity-MCP copilot-instructions.md
Copilot instructions for IvanMurzak/Unity-MCP, covering project guidelines, critical rules, no c# reflection for private access, code review and code style.
Unity-MCP CLAUDE.md
Claude Code instructions for IvanMurzak/Unity-MCP, covering claude.md, what this is, build / run, project constitution and find detail in.
dx-toolkit AGENTS.md
Lean maintainer guide for the You.com DX Toolkit monorepo.
shortcuts-mcp CLAUDE.md
Instructions for foxtrottwist/shortcuts-mcp, covering claude.md, essential commands, test cli discovery, test applescript execution and architecture overview.
agent-toolbox CLAUDE.md
Instructions for Vincentwei1021/agent-toolbox, covering claude.md — agent toolbox api, project overview, architecture, tech stack and build & run.
highchart-mcp-server CLAUDE.md
Claude Code instructions for hasnaintypes/highchart-mcp-server, covering claude.md, project overview, commands, architecture and chart engine.