codebase: Instructions file for GitHub Copilot

.github/instructions/prompt.instructions.md

codebase prompt.instructions.md is an instructions file for GitHub Copilot from JimmyPaolini/codebase. It costs 1,216 tokens per session, scanned A, a copy of custom_github_copilot_agent_builder prompt.instructions.md, MIT.

Guidelines for creating prompt files that give GitHub Copilot reusable instructions for coding tasks.

In plain words
What is it for?
They are for writing Copilot prompts with clear descriptions, names, agents, models, and available tools.
Why use it?
They help prompts stay consistent, understandable, and limited to the tools and behavior a task needs.

Instructions file for GitHub Copilot

Written for GitHub Copilot: a Copilot instructions file.

This is JimmyPaolini/codebase's own configuration. It tells GitHub Copilot how to work on codebase itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything codebase configures →

Reuse

Borrowing it

Nothing to install: this file belongs to JimmyPaolini/codebase. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/JimmyPaolini/codebase/main/.github/instructions/prompt.instructions.md
Clone the repo
git clone --depth 1 https://github.com/JimmyPaolini/codebase

Made for: GitHub Copilot.

Wrote 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.

agentmods badge for codebase prompt.instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/jimmypaolini/codebase/prompt.svg)](https://agentmods.dev/instructions/jimmypaolini/codebase/prompt)
Your own site
<a href="https://agentmods.dev/instructions/jimmypaolini/codebase/prompt"><img src="https://agentmods.dev/badge/instructions/jimmypaolini/codebase/prompt.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,216 This file is loaded in full into every session.
When invoked 1,216 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod 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 5.1 $0.01216 $0.01216
Opus 5 $0.00608 $0.00608
Sonnet 5 $0.00243 $0.00243
Haiku 4.5 $0.00122 $0.00122

Measured 4d ago against content hash b7a2e08449a5, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

codebase prompt.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.

Origin

This is a copy

100% identical to custom_github_copilot_agent_builder prompt.instructions.md — 37 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.github/instructions/prompt.instructions.md · 100 lines

How it starts

The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Copilot Prompt Files Guidelines

Instructions for creating effective and maintainable prompt files that guide GitHub Copilot in delivering consistent, high-quality outcomes across any repository.

Scope and Principles

  • Target audience: maintainers and contributors authoring reusable prompts for Copilot Chat.
  • Goals: predictable behavior, clear expectations, minimal permissions, and portability across repositories.
  • Primary references: VS Code documentation on prompt files and organization-specific conventions.

Frontmatter Requirements

Every prompt file should include YAML frontmatter with the following fields:

Required/Recommended Fields

Field Required Description
description Recommended A short description of the prompt (single sentence, actionable outcome)
name Optional The name shown after typing / in chat. Defaults to filename if not specified
agent Recommended The agent to use: ask, edit, agent, or a custom agent name. Defaults to current agent
model Optional The language model to use. Defaults to the currently selected model
tools Optional List of tool/tool set names available for this prompt
argument-hint Optional Hint text shown in chat input to guide user interaction

Guidelines

  • Use consistent quoting (single quotes recommended) and keep one field per line for readability and version control clarity
  • If tools are specified and the current agent is ask or edit, the default agent becomes agent
  • Preserve any additional metadata (language, tags, visibility, etc.) required by your organization

Read the full file on GitHub · 100 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. 4d ago First seen · 100 lines · 1,216 tokens per session scan A b7a2e08449a5

Subscribe to this mod's changes

codebase prompt.instructions.md is an instructions file published in the GitHub repository JimmyPaolini/codebase (0 stars, last pushed today), licensed MIT. It adds 1,216 tokens to every session, about $0.0061 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to custom_github_copilot_agent_builder prompt.instructions.md, differing in 37 lines, and is treated as a copy.

Related

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.

openai/codex · 5,182 tokens

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).

microsoft/vscode · 6,785 tokens

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.

vercel/next.js · 7,296 tokens

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.

langchain-ai/langchain · 4,469 tokens

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).

microsoft/vscode · 5,001 tokens

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.

github/spec-kit · 7,104 tokens