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/microsoft/cat-agent-skills/copilot-instructionsgit clone --depth 1 https://github.com/microsoft/cat-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/microsoft/cat-agent-skills/copilot-instructions)<a href="https://agentmods.dev/instructions/microsoft/cat-agent-skills/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/microsoft/cat-agent-skills/copilot-instructions.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 | $0.02932 | $0.02932 |
| Opus 5 | $0.01466 | $0.01466 |
| Sonnet 5 | $0.00586 | $0.00586 |
| Haiku 4.5 | $0.00293 | $0.00293 |
Grade A, and why
cat-agent-skills copilot-instructions.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 4d 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 — 198 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Copilot instructions for cat-agent-skills
This repo is a gallery of reusable Agent Skills. Contributors add one
submission under submissions/<slug>/ (a metadata.json sidecar plus exactly
one payload — an unpacked SKILL.md skill, a .zip, or a Scout .json); CI
generates the published page and download bundle. See
CONTRIBUTING.md and
submissions/README.md for the full rules.
Code review rules
When reviewing a pull request, check the following in addition to CI:
The bar: block real problems, not style
These checks are a merge gate, not a copy-edit. Skills are human-authored prose and code; treat the author's wording, formatting, and structure as theirs. Only post a comment you could defend as "must fix before merge." If the worst case is "could be tidier" or "slightly inconsistent," say nothing — prefer zero comments over a nit.
Block-worthy — do raise (the rest of this section defines these):
- Executable steps, runtime dependencies, or paths that won't run on a targeted platform (see Platform fit vs. executable code).
- Human-facing prose leaking into the agent-facing
SKILL.md, or setup/adoption guidance with nowhere to live (see Human-facing vs. agent-facing content). - Submission-hygiene breaks: mixed-scope PR, hand-committed generated artifacts,
wrong file layout, invalid or renamed required
metadata.jsonfields,name/slug mismatch, or a payload that isn't aSKILL.md/.zip/ Scout.json. - Anything that breaks CI, or is a security / privacy problem (secrets, data exfiltration, harmful content).
Not block-worthy — do NOT raise:
- Writing style in the skill's own text — wording, tone, grammar, capitalization, heading style, and punctuation, including em-dashes, hyphens, and Oxford commas. A skill telling itself "no em-dashes in output" is a rule for the generated text, not for the instructions that describe it; do not flag em-dashes (or any other "banned" token) in the playbook's own prose. Raise it only if the token appears inside a literal example/template the agent emits verbatim.
- Internal-consistency and "you could also…" nits that don't change whether the skill runs or what it produces.
- Cosmetic
metadata.jsonpreferences —updatedAt/ date freshness, optional-field bikeshedding — as long as the required fields are present and valid. - Generated artifacts CI commits back (
src/content/**,public/bundles/**): never flag their presence, content, or that a PR "also changes" them — they are CI-owned, not the contributor's edit. - The same point on many lines. Make it once, in one thread; don't open a thread per occurrence.
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.
- 4d ago First seen · 198 lines · 2,932 tokens per session scan A ab2ba279af1f
cat-agent-skills copilot-instructions.md is an instructions file published in the GitHub repository microsoft/cat-agent-skills (63 stars, last pushed 2d ago), licensed MIT. It adds 2,932 tokens to every session, about $0.0147 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
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).
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.
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.
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 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).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.