A single CLAUDE.md file to improve Claude Code behavior on LLM coding pitfalls.
"The models make wrong assumptions on your behalf and just run along with them without checking. They don't manage their confusion, don't seek clarifications, don't surface inconsistencies, don't present tradeoffs, don't push back when they should."
"They really like to overcomplicate code and APIs, bloat abstractions, don't clean up dead code... implement a bloated construction over 1000 lines when 100 would do."
"They still sometimes change/remove comments and code they don't sufficiently understand as side effects, even if orthogonal to the task."
Four principles in one file that directly address these issues:
| Principle | Addresses |
|---|---|
| Think Before Coding | Wrong assumptions, hidden confusion, missing tradeoffs |
| Simplicity First | Overcomplication, bloated abstractions |
| Surgical Changes | Orthogonal edits, touching code you shouldn't |
| Goal-Driven Execution | Leverage through tests-first, verifiable success criteria |
Don't assume. Don't hide confusion. Surface tradeoffs.
LLMs often pick an interpretation silently and run with it. This principle forces explicit reasoning:
- State assumptions explicitly — If uncertain, ask rather than guess
- Present multiple interpretations — Don't pick silently when ambiguity exists
- Push back when warranted — If a simpler approach exists, say so
- Stop when confused — Name what's unclear and ask for clarification
Minimum code that solves the problem. Nothing speculative.
Combat the tendency toward overengineering:
- 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 200 lines could be 50, rewrite it
The test: Would a senior engineer say this is overcomplicated? If yes, simplify.
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.
Define success criteria. Loop until verified.
Transform imperative tasks into verifiable goals:
| Instead of... | Transform to... |
|---|---|
| "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 the LLM loop independently. Weak criteria ("make it work") require constant clarification.
Option A: Claude Code Plugin (recommended)
From within Claude Code, first add the marketplace:
/plugin marketplace add sudo-erasmus/Claude Code Guidelines
Then install the plugin:
/plugin install sudo-erasmus-skills@erasmus-skills
This installs the guidelines as a Claude Code plugin, making the skill available across all your projects.
Option B: CLAUDE.md (per-project)
New project:
curl -o CLAUDE.md https://raw.githubusercontent.com/sudo-erasmus/Claude Code Guidelines/main/CLAUDE.mdExisting project (append):
echo "" >> CLAUDE.md
curl https://raw.githubusercontent.com/sudo-erasmus/Claude Code Guidelines/main/CLAUDE.md >> CLAUDE.mdFrom Andrej:
"LLMs are exceptionally good at looping until they meet specific goals... Don't tell it what to do, give it success criteria and watch it go."
The "Goal-Driven Execution" principle captures this: transform imperative instructions into declarative goals with verification loops.
These guidelines are working if you see:
- Fewer unnecessary changes in diffs — Only requested changes appear
- Fewer rewrites due to overcomplication — Code is simple the first time
- Clarifying questions come before implementation — Not after mistakes
- Clean, minimal PRs — No drive-by refactoring or "improvements"
These guidelines are designed to be merged with project-specific instructions. Add them to your existing CLAUDE.md or create a new one.
For project-specific rules, add sections like:
## Project-Specific Guidelines
- Use TypeScript strict mode
- All API endpoints must have tests
- Follow the existing error handling patterns in `src/utils/errors.ts`These guidelines bias toward caution over speed. For trivial tasks (simple typo fixes, obvious one-liners), use judgment — not every change needs the full rigor.
The goal is reducing costly mistakes on non-trivial work, not slowing down simple tasks.
PERSONAL USE LICENSE
Copyright (c) 2026 Isaiah Swanson-Sparks. All rights reserved.
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
NO SUPPORT
The author does not offer support for this repository. Questions, pull
requests, and issue reports from third parties may be closed without
response. This is not unkindness; it is the scope the project was designed
for.
NO SECURITY CLAIMS
This repository is a working procedure, not a security certification. It
does not claim to defend against any specific adversary class, does not
guarantee any compliance standard, and does not substitute for
professional security review of a production environment.
FUTURE LICENSE CHANGE
The author reserves the right to relicense this repository under a more
permissive license (such as MIT, Apache 2.0, or similar) at a later date
if and when the repository becomes general-purpose enough to be useful to
others. Until such a relicensing is announced, this personal-use license
applies.