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/timothywarner/copilot-dev/claude-mdgit clone --depth 1 https://github.com/timothywarner/copilot-devWhat 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 | $0.02489 | $0.02489 |
| Opus 5 | $0.01244 | $0.01244 |
| Sonnet 5 | $0.00498 | $0.00498 |
| Haiku 4.5 | $0.00249 | $0.00249 |
Grade A, and why
copilot-dev CLAUDE.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 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.
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 — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Repository Purpose
Teaching repository for GitHub Copilot for Developers — Tim Warner's 4-hour O'Reilly Live Training. Two things ship from here:
- Course materials — slide deck, course plan, tutorials, certification notes, news.
- A working Node demo app (
/src) that doubles as the Segment 3 / 4 demo for the cloud agent, Custom Agents, and Agent Skills.
Treat the source of truth for "what's current in Copilot" as README.md and the newest COURSE_PLAN_*.md. They are refreshed every delivery (current: COURSE_PLAN_JULY_2026.md, verified 2026-07-21 — AI Credits now live, Copilot Max tier, GPT-5.6 family, Claude Sonnet 5 and Opus 4.8, cloud agent rename, Copilot Vision GA). When updating model names, prices, or feature GAs, update those two files first; this CLAUDE.md should stay structural.
Superseded material to never reintroduce: Copilot Extensions (disabled Nov 10, 2025), premium requests as the billing model (legacy since June 1, 2026), "coding agent" as the primary term (renamed to cloud agent in April 2026), and gh copilot as the agentic CLI (the package is @github/copilot).
Repository Layout
/ README.md, CLAUDE.md, AGENTS.md, COURSE_PLAN_*.md, *.pptx
/docs Tutorials, info articles, reference inputs (NOT code)
/docs/references Microsoft Writing Style Guide + fictional-company pool
/docs/certification GH-300 exam objectives and study notes
/src Node + Express demo app + sample data
/scripts Helper scripts (PowerShell metrics report)
/.github Copilot customization examples (also configures THIS repo)
/archive Historical course materials — do not maintain unless explicitly asked
Convention: course plan + PPTX at root; prose under /docs; code under /src and /scripts. Don't put new tutorials at root.
Key Architectural Insight: .github/ is dual-purpose
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.
- 2d ago First seen · 137 lines · 2,489 tokens per session scan A 775b2f0fdfd1
copilot-dev CLAUDE.md is an instructions file published in the GitHub repository timothywarner/copilot-dev (46 stars, last pushed 29d ago), licensed MIT. It adds 2,489 tokens to every session, about $0.0124 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
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.
buildNext
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
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, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit 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.
langchain 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.