behavioral-guidelines

behavioral-guidelines is a skill for Claude Code, Codex from ThibautBaissac/rails_ai_agents. It costs 46 tokens per session (525 once invoked), scanned A, a copy of andrej-karpathy, MIT.

Practical rules for coding agents that encourage simple solutions, careful assumptions, small changes, and clear checks for success.

In plain words
What is it for?
Use them when writing, reviewing, or refactoring code to clarify uncertainties, limit the scope of edits, and define how the result will be tested.
Why use it?
They reduce common mistakes such as unnecessary complexity, silent guesses, unrelated refactoring, and changes that are difficult to verify.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit Use them when writing, reviewing, or refactoring code to clarify uncertainties, limit the scope of edits, and define how the result will be tested.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/thibautbaissac/rails_ai_agents/behavioral-guidelines
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add ThibautBaissac/rails_ai_agents --skill behavioral-guidelines
Clone the repo
git clone --depth 1 https://github.com/ThibautBaissac/rails_ai_agents

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for behavioral-guidelines

README.md
[![agentmods](https://agentmods.dev/badge/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines/github.svg)](https://agentmods.dev/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines)
Your own site
<a href="https://agentmods.dev/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines"><img src="https://agentmods.dev/badge/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for behavioral-guidelines

Your own site · 80×15
<a href="https://agentmods.dev/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines"><img src="https://agentmods.dev/badge/skills/thibautbaissac/rails_ai_agents/behavioral-guidelines.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 525 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 89% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00046 $0.00525
Opus 5.5 $0.00018 $0.00210
Sonnet 5.5 $0.00009 $0.00105
Haiku 4.5 $0.00005 $0.00052

Measured 2mo ago against content hash 207fd93026c6, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

behavioral-guidelines scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

89% identical to andrej-karpathy — 73 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/behavioral-guidelines/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Guidelines

Behavioral guidelines to reduce common LLM coding mistakes.

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.

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.

Read the full file on GitHub · 67 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2mo ago First seen · 67 lines · 46 tokens per session scan A 207fd93026c6

Subscribe to this mod's changes

behavioral-guidelines is a skill published in the GitHub repository ThibautBaissac/rails_ai_agents (672 stars, last pushed 5mo ago), licensed MIT. It adds 46 tokens to every session and 525 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 89% identical to andrej-karpathy, differing in 73 lines, and is treated as a copy.

Related

behavioral-guidelines compared with skills from other repositories

behavioral-guidelines next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
behavioral-guidelinesThibautBaissac/rails_ai_agentsSkill6725mo agoMITA46Claude Code, Codex
imagegenopenai/codexSkill133kyesterdayApache-2.0A113Codex
playwright-climicrosoft/playwrightSkill99kyesterdayApache-2.0A19Claude Code
local-ai-agentsmicrosoft/ai-agents-for-beginnersSkill79k4d agoMITA200Claude Code, Codex
systematic-debuggingobra/superpowersSkill313k3d agoMITA21Claude Code
next-cache-components-adoptionvercel/next.jsSkill143ktodayMITA95Claude Code
next-partial-prefetching-adoptionvercel/next.jsSkill143ktodayMITA103Claude Code