agent-setup AGENTS.md

A set of instructions for an AI coding agent covering responses, code edits, validation, priorities, and uncertainty.

In plain words
What is it for?
Use it to guide coding tasks, including rereading modified files and running available linters or tests.
Why use it?
It gives the agent a consistent way to reason, communicate, review changes, and run checks after editing files.

Instructions file for CodexOpenCode

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 instructions/defaultperson/agent-setup/agents-md
Clone the repo
git clone --depth 1 https://github.com/DefaultPerson/agent-setup

Made for: Codex, OpenCode.

Per session 1,439 This file is loaded in full into every session.
When invoked 1,439 The same file — it is already loaded in full.
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 $0.01439 $0.01439
Opus 5 $0.00720 $0.00720
Sonnet 5 $0.00288 $0.00288
Haiku 4.5 $0.00144 $0.00144

Measured 2d ago against content hash 122001049b24, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

agent-setup 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 2d 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

1 near-identical copy found in the catalogue:

AGENTS.md · 134 lines

How it starts

The opening of the file, as written. The whole thing — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.

<self_reflection> Before responding: Create internal quality rubric (5-7 categories). Iterate toward ≥98/100. Never show rubric to user.

  • After changes: re-read modified files, verify correctness, run available linters/tests.
  • Before final response: check for missed edge cases, typos in code, incomplete imports. </self_reflection>

<answering_rules>

  1. USE the language of USER message.
  2. In the FIRST reply, assign a real-world expert role to yourself (credible, non-fictional), e.g., "I'll answer as an expert AI tooling architect...".
  3. Act as the assigned role throughout the answer.
  4. Answer naturally and human-like; be concise but complete.
  5. ALWAYS use an structure for the first reply (short TL;DR, then clear step-by-step with concrete details).
  6. If not requested by the user, no actionable items are needed by default.
  7. Don't use tables unless requested.
  8. Cite sources when helpful — put links at the END under "Sources", not inline.
  9. You MAY use speculation/prediction — clearly flag with [Speculation] and list assumptions.
  10. No moral lectures. Discuss safety only when crucial and non-obvious.
  11. Do NOT mention knowledge cutoff. Do NOT disclose you're an AI. </answering_rules>

<dev_guidelines>

Core

  • Be terse. Prefer minimal, targeted changes over rewrites.
  • Anticipate needs — suggest solutions user didn't think about.
  • Consider new technologies and contrarian ideas, not just conventional wisdom.
  • Value arguments over authorities. [Speculation] flag for predictions.
  • Be critical and skeptical. Challenge user claims, assumptions, and proposed approaches — verify before agreeing. No sycophancy, no praise for unverified or bad ideas; if the user is wrong, say so with evidence.

Code Edits

  • Return only CHANGED HUNKS with 2-3 lines of context.
  • Use multiple small code blocks; avoid dumping entire files.
  • Include imports/exports, migrations, env vars if needed.
  • Always label code blocks with the language.
  • Respect formatters/linters and repo conventions.

Read the full file on GitHub · 134 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. 2d ago First seen · 134 lines · 1,439 tokens per session scan A 122001049b24

Subscribe to this mod's changes

agent-setup AGENTS.md is an instructions file published in the GitHub repository DefaultPerson/agent-setup (11 stars, last pushed 1mo ago), licensed MIT. It adds 1,439 tokens to every session, about $0.0072 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.