anchor: Instructions file for GitHub Copilot

GitHub Copilot Instructions

All project rules are defined in AGENTS.md. Read it before writing any code.

Required Reading

Before any task, read these files:

• AGENTS.md — All project rules and conventions
• DEEPDIVE.md — System architecture narrative
• docs/ — Project documentation

Critical Rules

1. No dead code — Remove unused functions, imports, variables immediately (Section 1)
2. Test-first — Write tests before code, verify all pass before committing (Section 8)
3. Full cleanup sweep before every commit:

   ruff check . && ruff format . && vulture . && mypy .
   

4. tests/ folder — All tests and random scripts go here; always in .gitignore (Section 5)
5. docs/ and research/ — Create for every new project (Section 5)
6. Human-sounding commits — Explain WHY changes were made, not just WHAT changed (Section 15)
7. DEEPDIVE.md — Update after any architectural change (Section 5)
8. PR size limit — 800 lines max, 500 for complex logic (Section 33)
9. Decision ladder — YAGNI → stdlib → native → existing dep → one line → minimum (Section 50.1)
10. Tradeoff comments — Name the ceiling and upgrade trigger for any intentional shortcut (Section 50.2)
11. Pre-commit hooks mandatory — Install and run before every commit (Section 37)

Prohibited Actions

• NEVER create PRs, issues, or GitHub activity without explicit user approval (Section 2)
• NEVER leave dead code, stubs, or silent exception handlers (Section 1)
• NEVER commit without running the full lint/vulture sweep first (Section 9)
• NEVER skip pre-commit hooks (Section 37)
• NEVER submit a PR over 800 lines (Section 33)

Project Structure

project/
├── src/              # Source code
├── tests/            # All tests (gitignored)
├── docs/             # Architecture docs
├── research/         # Research files
├── DEEPDIVE.md       # System narrative
├── AGENTS.md         # This file (entry point)
├── skills/           # Full rule text — lazy-loaded by task
└── TODO.md           # Task tracking