Copilot Forgets Everything. Make It Stop.

You open a new Copilot chat and explain everything again.

Your stack. Folder structure. That “no default exports” rule.

Copilot writes code, but forgets context.

This isn’t a bug though. LLMs are stateless, every chat starts fresh.

The good part? You can fix it.

The Problem Has a Name

You’re dealing with three problems:

• The Blank Slate: Every session starts from zero.

• Correction Amnesia: You fix a mistake. Next session, same mistake.

• Standards Drift: Your team has patterns. Copilot ignores them. Code becomes inconsistent.

Each problem has a different fix. Let's go through them one by one.

The Instructions File (Your Copilot Brief)

Create this file:

your-project/
└── .github/
    └── copilot-instructions.md

Copilot reads it at the start of every chat. No setup.

Think of it as your team’s “how we work” doc.

Example:

## Stack
- React 18, TypeScript (strict), Tailwind CSS
- Node.js + Express + Prisma + PostgreSQL
- Testing: Vitest + React Testing Library
- Package manager: pnpm only

## Rules
- Named exports only — no default exports
- No `any` types
- Every API route uses `authenticate`
- Handle nulls explicitly — no optional chaining on Prisma results
- Conventional Commits: feat(scope): message

Now everyone gets the same baseline.

Scoped Rules (Right Rules, Right Files)

One file works… until it grows.

Frontend, backend, and tests follow different rules. A single file mixes context.

Use scoped files:

.github/
├── copilot-instructions.md
└── instructions/
    ├── frontend.instructions.md
    ├── backend.instructions.md
    └── testing.instructions.md

Each file defines where it applies:

---
applyTo: "src/components/**/*.tsx"
---

## Component Rules
- Functional components only
- Props interface named `[ComponentName]Props`
- Use `cn()` for conditional classes
- No inline styles

Now Copilot gets relevant rules only.

The Memory Tool (Fix Repeated Mistakes)

Copilot has a memory tool in VS Code (preview, enabled by default).

When you correct it, make it persistent:

Remember: never use optional chaining on Prisma query results. 
Always handle null with an explicit if-check.

It stores this and applies it in future sessions.

Memory types:

User memory (all projects)

Remember I prefer async/await over .then()

Repository memory (this project)

Remember we use App Router (March 2026)
Remember UserAvatar breaks in Server Components

Session memory (current chat only)

Key habit: When you fix a repeated mistake, tell it to remember.

Check memory with Chat: Show Memory Files.

Note: Memory tool is in preview, enable via github.copilot.chat.tools.memory.enabled.

Prompt Files (Stop Repeating Yourself)

If you repeat prompts, create a prompt file:

.github/prompts/code-review.prompt.md

Use it with /code-review.

Example:

---
name: "code-review"
description: "Reviewstagedchanges"
mode: "ask"
---

Review staged changes.

Flag:
- Must Fix — bugs, auth, unsafe types
- Should Fix — standards, missing tests
- Suggestion — improvements

Reference [copilot-instructions.md](../copilot-instructions.md).

Now your team shares the same workflow.

Other useful prompts:

• /new-component
• /new-migration
• /write-tests

The Full Picture

.github/
├── copilot-instructions.md
├── instructions/
│   ├── frontend.instructions.md
│   ├── backend.instructions.md
│   └── testing.instructions.md
└── prompts/
    ├── code-review.prompt.md
    ├── new-component.prompt.md
    └── new-migration.prompt.md

Plus memory running in the background.

Just Start With One Thing

You don’t need everything today.

Start with copilot-instructions.md. Add your stack and a few rules. Commit it. See the difference.

Then:

• Add scoped files when needed
• Save repeated fixes to memory
• Create prompt files when repetition appears

The model won’t change. But your context can improve every week.