PROJ001errorFree tier

missing-ai-context-file

Projects edited by AI assistants should ship a context file (CLAUDE.md, AGENTS.md, .cursorrules, or equivalent)

Applies to: Project-level

Why this matters

Modern codebases are increasingly written and modified by AI coding assistants (Claude Code, Cursor, Copilot, Aider, and others). Without a context file at the repo root the assistant starts every session blind: it doesn't know the architecture, the conventions, the commands to run tests, which libraries you've already chosen, or what's load-bearing and must not change. Every session re-discovers this from scratch, and every re-discovery is a fresh chance to pick the wrong pattern, invent a helper that already exists, break a convention, or delete something important. A single CLAUDE.md / AGENTS.md file turns that blindness into onboarding: the assistant (and any new human) reads the file once and starts making informed decisions. The cost of writing the file is an hour; the cost of not having it compounds across every AI-assisted change the team ships.

Catch it before it ships

pip install stablestack # or: npx stablestackstablestack # scans your project, PROJ001 includedstablestack explain PROJ001

False positive in your codebase? Suppress a single line with # noqa: PROJ001