github-copilot-cli copilot-instructions.md

A set of project instructions for GitHub Copilot CLI, GitHub's terminal-based AI coding agent. It documents the project's context, file layout, naming rules, commit format, agents, skills, hooks, and MCP settings.

In plain words
What is it for?
Use it to configure Copilot CLI workspaces, organize customization files under .github, follow Conventional Commits, and define custom agents and skills.
Why use it?
It gives Copilot consistent project-specific guidance instead of making it infer conventions during each session.

Instructions file for GitHub Copilot

Install

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.

agentmods
npx agentmods add instructions/trsdn/github-copilot-cli/copilot-instructions
Clone the repo
git clone --depth 1 https://github.com/trsdn/github-copilot-cli

Made for: GitHub Copilot.

Per session 592 This file is loaded in full into every session.
When invoked 592 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.00592 $0.00592
Opus 5 $0.00296 $0.00296
Sonnet 5 $0.00118 $0.00118
Haiku 4.5 $0.00059 $0.00059

Measured yesterday against content hash 3938a61eb0d0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

github-copilot-cli 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 yesterday.

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.

.github/copilot-instructions.md · 50 lines

How it starts

The opening of the file, as written. The whole thing — 50 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Copilot Instructions

These instructions are automatically applied to every Copilot CLI session in this workspace.

Project Context

This is a GitHub Copilot CLI Customization Blueprint — a template repository for bootstrapping custom agents, instructions, skills, hooks, plugins, and MCP configurations for Copilot CLI usage, including sessions launched from the VS Code integrated terminal.

This blueprint is CLI-first — no VS Code dependency, but compatible customization formats should remain useful from VS Code when the same files are supported there.

Conventions

  • Repository customization files live under .github/ (agents, skills, instructions, hooks, MCP)
  • Use Conventional Commits for all commit messages: <type>(<scope>): <description>
  • Allowed types: feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert
  • Agent files: .agent.md with YAML frontmatter (description required, name and tools recommended)
  • Agent frontmatter can include target, model, mcp-servers, user-invocable, and disable-model-invocation
  • Skill files: SKILL.md in a named directory under .github/skills/<name>/
  • Skill frontmatter requires name and description; optional fields include license, allowed-tools, user-invocable, and disable-model-invocation
  • Instruction files: *.instructions.md with YAML frontmatter (applyTo glob required)
  • Hook files: JSON files under .github/hooks/*.json with version: 1
  • MCP files: .github/mcp.json for repository MCP config, .mcp.json for workspace MCP config
  • For cross-tool compatibility, also support CLAUDE.md, GEMINI.md, and AGENTS.md at repo root

File Structure

.github/
├── agents/           # Custom agent profiles (.agent.md)
├── instructions/     # Scoped instruction files (*.instructions.md)
├── skills/           # Agent Skills (each in its own directory with SKILL.md)
├── hooks/            # Optional Copilot CLI hook configuration (*.json)
├── workflows/        # GitHub Actions (release, validate, commit-lint)
├── mcp.json          # Optional repository MCP configuration
└── copilot-instructions.md  # This file
AGENTS.md             # Root-level agent instructions

Read the full file on GitHub · 50 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. yesterday First seen · 50 lines · 592 tokens per session scan A 3938a61eb0d0

Subscribe to this mod's changes

github-copilot-cli copilot-instructions.md is an instructions file published in the GitHub repository trsdn/github-copilot-cli (1 stars, last pushed 2mo ago), licensed MIT. It adds 592 tokens to every session, about $0.0030 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 2026-08-31.