GitHub Copilot custom instructions
https://docs.github.com/copilot/customizing-copilot/adding-custom-instructions-for-github-copilot
.github/copilot-instructions.md repo-wide; .github/instructions/<name>.instructions.md for path-scoped rules with YAML frontmatter ( applyTo glob). Persists style, test conventions, language preferences.
At a glance
- Type
- .github/copilot-instructions.md + path-scoped
- Tier
- T1
- Section
- File-backed / editor paradigms
- Created
- 2024 (public preview launched October 2024 in VS Code; .github/copilot-instructions.md format)
- Latest release
- n/a — vendor feature of GitHub Copilot (not a versioned repo); rolling updates via Copilot changelog
- License
- n/a — feature of GitHub Copilot (proprietary); instructions files are user-owned under repo license
- Pricing
- not applicable — file pattern included in GitHub Copilot subscription ($10/mo individual; $19/mo business; $39/mo e…
- Funding
- not applicable — not commercial
Taxonomy
- storage
- file
- retrieval
- injection
- persistence
- cross-session
- update
- overwrite
- unit
- document
- governance
- user-controllable
- conflict
- manual
When to use
Optimised for: simplicity / git-versioned / human-readable
Anti-fit: not for non-coding / non-IDE use cases
Pros & cons
Pros
Reaches the largest installed base of AI-using developers; integrated where developers already work; backed by GitHub's persistence.
Cons
Repository-scoped instructions only — no persistent learning; less expressive than Cursor Rules' selector model.
Claims & capabilities
Vendor-supported across VS Code, JetBrains, GitHub.com chat.
Technical surface
- API surface
- not applicable — IDE feature
- Backend storage
- file (.github/copilot-instructions.md)
- Deployment
- not applicable — GitHub-hosted; no separate deployment
- Embedding model
- not applicable — instruction file
- Multi-tenancy
- hard-isolation (per repo/org)
- MCP
- not applicable — file-as-memory paradigm (no API surface)
- A2A
- not applicable — file-as-memory paradigm
- OpenTelemetry
- not applicable — file-as-memory paradigm
Compare GitHub Copilot custom instructions with…
Similar systems
Other file-backed / editor paradigms in the catalog, ranked by inbound references.
- Cline .clinerules T2
.clinerules single file or .clinerules/ directory of numbered .md files (e.g. 01-style.md ). Global at ~/.cline/rules/ . Files version-controlled and AI-editable — Cline can write back. Toggleable per-session via UI.
- AGENTS.md T1
AGENTS.md at repo root (and ~/.codex/AGENTS.md for global); hierarchical concatenation from root to cwd. Persists build/test commands, conventions, architecture overview, security constraints, git workflow.
- Aider CONVENTIONS.md / .aider.conf.yml T2
CONVENTIONS.md (any name, loaded via --read or read: in config); .aider.conf.yml (home / git-root / cwd, last wins); .aiderignore (gitignore-syntax).
- CLAUDE.md T1
Markdown file injected at session start; reloaded post-compaction. Document-as-memory: human-readable, version-controlled, no extraction or vector store. Anthropic-canonical pattern; equivalent emerges in Cursor / Windsurf.
- Cline Memory Bank T2
memory-bank/ directory of Markdown: projectBrief.md , productContext.md , activeContext.md , systemPatterns.md , techContext.md , progress.md . Loaded in full at start of every task. Compensates for context-window reset between sessions.
- Continue.dev .continue/rules T2
.continue/rules/*.md at workspace root. YAML frontmatter: name , globs (file-pattern trigger), alwaysApply , description . Loaded lexicographically.