CLAUDE.md · cypress-io/cypress

Sections

1. Workflow Orchestration
2. Core Principles
3. Working Constraints

First lines (shown under the repo's MIT license)

# CLAUDE.md

## Workflow Orchestration

### 1. Plan Mode Default

- Enter plan mode for ANY non-trivial task (3+ steps or architectural decisions)
- If something goes sideways, STOP and re-plan immediately - don't keep pushing
- Use plan mode for verification steps, not just building
- Write detailed specs upfront to reduce ambiguity

### 2. Subagent Strategy

- Use subagents liberally to keep main context window clean
- Offload research, exploration, and parallel analysis to subagents
- For complex problems, throw more compute at it via subagents
- One task per subagent for focused execution

### 3. Self-Improvement Loop

- After ANY correction from the user: update the closest relevant `CLAUDE.md` file
- Write rules for yourself that prevent the same mistake

### 4. Verification Before Done

- Never mark a task complete without proving it works
- Diff behavior between main and your changes when relevant
- Ask yourself: "Would a staff engineer approve this?"
- Run relevant tests only, check logs, demonstrate correctness

### 5. Demand Elegance (Balanced)

- For non-trivial changes: pause and ask "is there a more elegant way?"
- If a fix feels hacky: "Knowing everything I know now, implement the elegant solution"
- Skip this for simple, obvious fixes - don't over-engineer
- Challenge your own work before presenting it

## Core Principles

- **Minimal Impact**: Changes should only touch what's necessary. Avoid introducing bugs.

## Working Constraints

- Worktrees must use a full `yarn` install in the worktree. Do not symlink `node_modules` or packages back to another checkout.
- Packaged-binary integration tests (`system-tests/test-binary`) need Docker and a built binary, so they do not run in the sandbox. When they are needed, provide the exact commands and ask the user to run them.
- System tests under `system-tests/test` do run in cloud containers once the monorepo is built. Run them yourself rather than handing them off; see [Running system tests](./AGENTS.md#running-system-tests).
- Keep follow-up work from the same task, such as review fixes and related instruction updates, on that task's branch. Create a separate branch only when the user asks for one.
- After committing a merge of `develop`, run `git diff --name-only origin/develop` and check that every file listed is in the PR's scope. The pre-commit hook runs `eslint --fix` on every staged file, merged-in ones included, and `package-json/order-properties` reorders keys in `package.json` files that `develop` committed unsorted. Restore any such file with `git checkout origin/develop -- <file>` and commit with `--no-verify`.
- Before committing or pushing, `yarn check-ts`, `yarn lint`, `yarn health-check` (knip), and relevant unit tests must pass locally. CI currently does not block expensive e2e jobs when these fail.

@AGENTS.md