# CLAUDE.md

Behavioral guidelines to reduce common LLM coding mistakes. Merge with project-specific instructions as needed.

**Tradeoff:** These guidelines bias toward caution over speed. For trivial tasks, use judgment.

## 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.

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.

**Exception — Tech debt must be fixed, not deferred:** When you discover a real bug,
broken behavior, or technical debt while working (even if it predates this change and
you didn't introduce it), fix it — do not use "not introduced by this round / pre-existing"
as a reason to leave it. Surface it, then handle it. (User directive, 2026-06-25, binding.)
This overrides the "don't fix what isn't broken" bias above *for genuine defects* — it does
not license cosmetic refactors or unrequested rewrites.

**Do it yourself — never offload work you can do (User directive, 2026-06-25, binding):**
If you have the tools to do something, DO IT — never tell the user to do it for you.
Read the logs yourself (`%LOCALAPPDATA%/Geomative/Geopro3/logs/geopro_*.log` via Bash/grep),
inspect data/fixtures yourself, build and link yourself (`build.bat app` via PowerShell),
diagnose by adding logging and then reading that log yourself. The ONLY things to ask the
user for are: (a) closing a running app so the exe can relink (LNK1104 — a lock only they can
release), and (b) genuine product decisions. Do not ask the user to read logs, inspect data,
run diagnostics, or interpret output — that is your job.

## 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]
```

Strong success criteria let you loop independently. Weak criteria ("make it work") require constant clarification.

---

**These guidelines are working if:** fewer unnecessary changes in diffs, fewer rewrites due to overcomplication, and clarifying questions come before implementation rather than after mistakes.