custom-skills: Instructions file for Codex

AGENTS.md

custom-skills AGENTS.md is an instructions file for Codex, OpenCode from ValorVie/custom-skills. It costs 1,493 tokens per session, scanned A, original, MIT.

An AGENTS.md instruction file for the custom-skills project. It tells the assistant to think before coding, prefer simple solutions, and make surgical changes.

In plain words
What is it for?
Use it to guide AI-assisted development in the ValorVie/custom-skills repository.
Why use it?
It helps keep coding work focused and avoids speculative features or unnecessary edits.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: $skill-name invocation.

This is ValorVie/custom-skills's own configuration. It tells Codex and OpenCode how to work on custom-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything custom-skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to ValorVie/custom-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/ValorVie/custom-skills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/ValorVie/custom-skills

Made for: Codex, OpenCode.

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 custom-skills AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/valorvie/custom-skills/agents-md.svg)](https://agentmods.dev/instructions/valorvie/custom-skills/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/valorvie/custom-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/valorvie/custom-skills/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,493 This file is loaded in full into every session.
When invoked 1,493 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.01493 $0.01493
Opus 5 $0.00746 $0.00746
Sonnet 5 $0.00299 $0.00299
Haiku 4.5 $0.00149 $0.00149

Measured 4d ago against content hash 352b6efc3e05, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

custom-skills AGENTS.md 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 4d 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

Copies of this mod

2 near-identical copies found in the catalogue:

AGENTS.md · 128 lines

How it starts

The opening of the file, as written. The whole thing — 128 lines — stays where its author put it; the contents beside it link to each section on GitHub.


Language

預設情況下,所有回應皆使用繁體中文

  • $humanizer-zh-tw SKILL 進行回應跟撰寫文件

Rules

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.

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"

Read the full file on GitHub · 128 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. 4d ago First seen · 128 lines · 1,493 tokens per session scan A 352b6efc3e05

Subscribe to this mod's changes

custom-skills AGENTS.md is an instructions file published in the GitHub repository ValorVie/custom-skills (5 stars, last pushed 7d ago), licensed MIT. It adds 1,493 tokens to every session, about $0.0075 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 2026-09-03.

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