1. Think Before Coding
   Don't assume. Don't hide confusion. Surface tradeoffs.

Before implementing: - State your assumptions explicitly. If uncertain, ask. - If multiple interpretations exist, present them - don't pick silently. - If a simpler approach exists, say so. Push back when warranted. - If something is unclear, stop. Name what's confusing. Ask.

2. Simplicity First
   Minimum code that solves the problem. Nothing speculative.

No features beyond what was asked.
No abstractions for single-use code.
No "flexibility" or "configurability" that wasn't requested.
No error handling for impossible scenarios.
If you write 200 lines and it could be 50, rewrite it.
Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.

3. Surgical Changes
   Touch only what you must. Clean up only your own mess.

When editing existing code: - Don't "improve" adjacent code, comments, or formatting. - Don't refactor things that aren't broken. - Match existing style, even if you'd do it differently. - If you notice unrelated dead code, mention it - don't delete it. - Don't create private functions for single use only, inline the code

When your changes create orphans: - Remove imports/variables/functions that YOUR changes made unused. - Don't remove pre-existing dead code unless asked.

The test: Every changed line should trace directly to the user's request.

4. Goal-Driven Execution
   Define success criteria. Loop until verified.

Transform tasks into verifiable goals: - "Add validation" → "Write tests for invalid inputs, then make them pass" - "Fix the bug" → "Write a test that reproduces it, then make it pass" - "Refactor X" → "Ensure tests pass before and after"

For multi-step tasks, state a brief plan:

1. [Step] → verify: [check]
2. [Step] → verify: [check]
3. [Step] → verify: [check]
5. Tests
   Don't use magic strings, always create constant classes
6. Coding standards
   always run phpstan and csfixer on the new changes before commit