simplicity-first

simplicity-first is a skill for Claude Code, Codex from DevelopersGlobal/ai-agent-skills. It costs 27 tokens per session (897 once invoked), scanned A, original, MIT.

A coding rule that keeps implementations to the smallest solution that meets the stated requirements. It avoids speculative features, early abstractions, and needless complexity.

In plain words
What is it for?
Use it when starting an implementation, reviewing generated code, or when a simple task begins growing into a complex system.
Why use it?
It reduces bloated code that is harder to understand, review, and maintain. It also keeps agents from solving problems that were never requested.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

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.

agentmods
npx agentmods add skills/developersglobal/ai-agent-skills/simplicity-first
Any agent
npx skills add DevelopersGlobal/ai-agent-skills --skill simplicity-first
Clone the repo
git clone --depth 1 https://github.com/DevelopersGlobal/ai-agent-skills

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 simplicity-first

README.md
[![agentmods](https://agentmods.dev/badge/skills/developersglobal/ai-agent-skills/simplicity-first.svg)](https://agentmods.dev/skills/developersglobal/ai-agent-skills/simplicity-first)
Your own site
<a href="https://agentmods.dev/skills/developersglobal/ai-agent-skills/simplicity-first"><img src="https://agentmods.dev/badge/skills/developersglobal/ai-agent-skills/simplicity-first.svg" alt="Measured on agentmods" height="20"></a>
Per session 27 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 897 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.00027 $0.00897
Opus 5 $0.00014 $0.00449
Sonnet 5 $0.00005 $0.00179
Haiku 4.5 $0.00003 $0.00090

Measured 6d ago against content hash 89cd16298134, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

simplicity-first 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 6d 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.

skills/simplicity-first/SKILL.md · 98 lines

How it starts

The opening of the file, as written. The whole thing — 98 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Overview

AI agents trend toward complexity. They add abstractions "for flexibility," error handling for impossible cases, and configuration for things that will never change. Left unchecked, they turn 50-line solutions into 500-line systems.

This skill enforces a hard constraint: write the minimum code that solves the stated problem and nothing more.

Andrej Karpathy's observation: "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."

When to Use

  • Starting any new implementation
  • When you feel the urge to add "just one more abstraction"
  • When reviewing your own generated code
  • When a simple task balloons into a complex solution

Process

Step 1: Define the Minimum Viable Solution

  1. State what the code must do — write it as a list of requirements.
  2. For each potential addition, ask: "Was this explicitly requested?"
    • If no → do not add it.
  3. Write the simplest possible implementation that satisfies each requirement.

Verify: You can trace every line of code back to a stated requirement.

Step 2: Apply the Simplicity Test

  1. After writing, read through the code and flag:

    • Abstractions used only once → inline them
    • Parameters never customized → hardcode them
    • Error handling for impossible scenarios → remove it
    • "Future-proofing" that wasn't asked for → delete it
    • Configuration flags for things that won't vary → remove them
  2. Ask: "Would a senior engineer call this overcomplicated?" If yes, simplify.

Verify: Each abstraction is used in at least 2 places; each parameter is actually varied.

Step 3: Count the Lines

  1. If your solution is more than 3× the length you'd expect for the task, something is wrong.
  2. Actively look for ways to reduce line count without sacrificing readability.

Rule of thumb: If 200 lines could be 50, rewrite it.

Verify: You've made at least one active attempt to reduce complexity.

Read the full file on GitHub · 98 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. 6d ago First seen · 98 lines · 27 tokens per session scan A 89cd16298134

Subscribe to this mod's changes

simplicity-first is a skill published in the GitHub repository DevelopersGlobal/ai-agent-skills (65 stars, last pushed 4mo ago), licensed MIT. It adds 27 tokens to every session and 897 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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