friday AGENTS.md

AGENTS.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.
• Do not over-engineer the solution; actively look for the simplest solution that satisfies the request.
• No abstractions for single-use code.
• No "flexibility" or "configurability" that wasn't requested.
• No error handling for impossible scenarios.
• Use established design patterns when they prevent tangled control flow or repeated ad hoc logic; don't add patterns preemptively.
• Use dependency injection when it makes dependencies explicit, improves readability, or simplifies testing; avoid hidden globals and hard-coded service construction in business logic.
• Default to a module-based file structure. Split code into separate files when responsibilities diverge, and move any function or component reused by multiple modules into its own shared file.
• Implement one function per file maximum.
• Use a one-word filename in 99% of cases; use longer names only when existing conventions or clarity require it.
• 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.
• Don't add code comments unless the user explicitly asks for them.
• If you notice unrelated dead code, mention it - don't delete it.
• When implementing a new feature, do not use patch-style or workaround implementations; implement the requested behavior directly in the relevant code, and do not create or run migrations unless explicitly requested.