Archon AGENTS.md

Archon AGENTS.md is an instructions file for Codex, OpenCode from coleam00/Archon. It costs 3,429 tokens per session, scanned A, original, MIT.

AGENTS.md instructions for coleam00/Archon, covering working on archon, read before changing code, product boundaries, engineering taste and prefer the smallest truthful system.

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/coleam00/archon/agents-md
Clone the repo
git clone --depth 1 https://github.com/coleam00/Archon

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 Archon AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/coleam00/archon/agents-md.svg)](https://agentmods.dev/instructions/coleam00/archon/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/coleam00/archon/agents-md"><img src="https://agentmods.dev/badge/instructions/coleam00/archon/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 3,429 This file is loaded in full into every session.
When invoked 3,429 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.03429 $0.03429
Opus 5 $0.01715 $0.01715
Sonnet 5 $0.00686 $0.00686
Haiku 4.5 $0.00343 $0.00343

Measured today against content hash c05a8c09d758, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

Archon 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 today.

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.

AGENTS.md · 195 lines

How it starts

The opening of the file, as written. The whole thing — 195 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Working on Archon

Archon is a self-hostable, governed agentic automation engine. It runs workflows that mix deterministic steps, AI agents, human gates, and audit trails. Coding automation is its most mature surface, but the engine is intended for general business operations too.

This file is the canonical project guidance for coding agents. Keep it short, durable, and about judgment. Put changing product direction in .archon/direction.md, workflow-language design in .archon/workflow-language-constitution.md, aspirational engineering craft and review values in .archon/engineering.md, user documentation in the docs site, and machine-checkable rules in code, types, tests, lint, or CI.

Read before changing code

  • Treat the source, its call sites, and its tests as the current evidence. The request defines the goal and constraints, but a prompt may describe old code.
  • Read every relevant consumer before changing a producer, contract, path, identifier, schema, or generated artifact.
  • Reproduce bugs when practical. If reproduction is impossible, establish another concrete causal chain before editing.
  • Do not trust a passing test by itself. Check that it exercises the behavior it claims to protect.
  • A question is read-only. Explain first; change code only when the user asks for a change.
  • Do not stop at editing. Finish the requested change and verify the outcome.
  • If the implementation keeps getting more complicated, stop and reconsider the model. Solve the underlying problem.

Product boundaries

  • Archon is a governed automation engine, not a replacement for the coding agents it orchestrates.
  • One install serves one operator or client. Client isolation belongs at the deployment layer. Multiple users within one install are supported and are not multi-tenancy.
  • Keep the conversation layer platform-agnostic. Platform adapters translate transport details; core behavior should not depend on Slack, Telegram, GitHub, Discord, CLI, or Web UI semantics.
  • Keep the core self-hostable. Do not make a proprietary hosted service a runtime dependency.
  • Keep the core small and flexible. Agentic engineering changes too quickly for one monolith to encode every useful workflow or integration; give users stable seams to assemble and extend the rest.
  • Treat bundled workflows as reference implementations, not a frozen compatibility surface.
  • A git worktree separates checkouts; it is not an execution or security sandbox.
  • Consult .archon/direction.md before making product-scope or architecture-direction decisions.

Read the full file on GitHub · 195 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. today First seen · 195 lines · 3,429 tokens per session scan A c05a8c09d758

Subscribe to this mod's changes

Archon AGENTS.md is an instructions file published in the GitHub repository coleam00/Archon (23,366 stars, last pushed yesterday), licensed MIT. It adds 3,429 tokens to every session, about $0.0171 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.