ALDC-AL-Development-Collection: Instructions file for GitHub Copilot

.github/copilot-instructions.md

ALDC-AL-Development-Collection copilot-instructions.md is an instructions file for GitHub Copilot from javiarmesto/ALDC-AL-Development-Collection. It costs 2,986 tokens per session, scanned C, original, MIT.

A set of GitHub Copilot instructions for developing AL extensions for Microsoft Dynamics 365 Business Central. It defines coding principles, agent routing, workflows, testing, permissions, and the language used for saved project documents.

In plain words
What is it for?
Use it to plan, build, debug, review, and test Business Central extensions while keeping saved plans and reports in English.
Why use it?
It gives Copilot consistent project guidance and helps prevent changes that violate the extension-only design or documentation rules.

Instructions file for GitHub Copilot

Written for GitHub Copilot: a Copilot instructions file. Also seen: mentions subagents.

This is javiarmesto/ALDC-AL-Development-Collection's own configuration. It tells GitHub Copilot how to work on ALDC-AL-Development-Collection 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 ALDC-AL-Development-Collection configures →

Needs its repository: it reads a path above its own folder, which exists only inside the repository. The line is **Pilot scope**: only `al-performance-review`, `al-security-review`, and `al-style-review` are enabled. Run `bash tools/bcquality/install.sh` to clone BCQuality.

Reuse

Borrowing it

Nothing to install: this file belongs to javiarmesto/ALDC-AL-Development-Collection. 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/javiarmesto/ALDC-AL-Development-Collection/main/.github/copilot-instructions.md
Clone the repo
git clone --depth 1 https://github.com/javiarmesto/ALDC-AL-Development-Collection

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 ALDC-AL-Development-Collection copilot-instructions.md

README.md
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Your own site
<a href="https://agentmods.dev/instructions/javiarmesto/aldc-al-development-collection/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/javiarmesto/aldc-al-development-collection/copilot-instructions/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for ALDC-AL-Development-Collection copilot-instructions.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/javiarmesto/aldc-al-development-collection/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/javiarmesto/aldc-al-development-collection/copilot-instructions.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,986 This file is loaded in full into every session.
When invoked 2,986 The same file — it is already loaded in full.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.02986 $0.02986
Opus 5 $0.01493 $0.01493
Sonnet 5 $0.00597 $0.00597
Haiku 4.5 $0.00299 $0.00299

Measured 9d ago against content hash 3631b9c980d7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade C, and why

ALDC-AL-Development-Collection copilot-instructions.md scanned grade C with 1 finding 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 9d 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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- Workspace-specific custom instructions for Copilot. Reference: https://code.visualstudio.com/docs/copilot/copilot-customization#_use-a-githubcopilotinstructionsmd-file -->
.github/copilot-instructions.md · 191 lines

How it starts

The opening of the file, as written. The whole thing — 191 lines — stays where its author put it; the contents beside it link to each section on GitHub.

GitHub Copilot Instructions for AL Development

Overview

This workspace contains AL (Application Language) code for Microsoft Dynamics 365 Business Central. It uses the ALDC Core v1.1 skills-based architecture: 4 agents + 11 skills + 6 workflows + 7 instructions.

Core Principles

These principles apply to ALL work in this repository:

  • Extension-only development — Never modify base application objects. Use tableextensions, pageextensions, event subscribers.
  • Human-in-the-Loop (HITL) — All critical decisions require user confirmation before proceeding.
  • TDD / spec-driven — Features follow the flow: spec.create → architecture → test-plan → implementation → review.
  • Least privilege — Generate only the minimum permissions required. Use XLIFF for all user-facing strings.
  • Output language: English — All persisted artifacts under .github/plans/** (architecture.md, spec.md, plan.md, phase-N-complete.md, plan-complete.md, test-plan.md, delivery.md, review reports, Dredd audit reports, BCQuality findings JSON) MUST be written in English regardless of the chat conversation language. Inline chat responses MAY follow the user's language; persisted artifacts stay in English.

Agent Routing

Choose the right agent for your task:

Intent Agent What it does
Designing, analyzing architecture, strategic decisions? @AL Architecture & Design Specialist Solution design, data modeling, integration strategy
Implementing, coding, debugging, fixing? @AL Implementation Specialist Tactical implementation with full AL MCP tools
Building a feature with TDD orchestration (plan → implement → review → commit)? @AL Development Conductor Orchestrates planning, implementation, and review subagents
Estimating a project, sizing, proposals? @AL Pre-Sales & Project Estimation Specialist PERT estimation, SWOT analysis, cost breakdown
Auditing code independently against BCQuality (changes vs main, or all)? @Dredd Independent read-only auditor; advisory verdict with citations

Read the full file on GitHub · 191 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. 9d ago First seen · 191 lines · 2,986 tokens per session scan C 3631b9c980d7

Subscribe to this mod's changes

ALDC-AL-Development-Collection copilot-instructions.md is an instructions file published in the GitHub repository javiarmesto/ALDC-AL-Development-Collection (103 stars, last pushed 2d ago), licensed MIT. It adds 2,986 tokens to every session, about $0.0149 per session on Opus 5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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