AtomisticSkills: Instructions file for Codex

AGENTS.md

AtomisticSkills AGENTS.md is an instructions file for Codex, OpenCode from learningmatter-mit/AtomisticSkills. It costs 704 tokens per session, scanned A, original, MIT.

A set of instructions for agents working in the AtomisticSkills research framework. It describes the project's tools, skills, workflows, and rules for carrying out atomistic simulations and related research tasks.

In plain words
What is it for?
Use it as the main guidance file when an agent is exploring, running, or extending AtomisticSkills workflows.
Why use it?
It gives coding agents the context they need to follow the repository's conventions and choose the right level of automation. This helps keep research tasks, scripts, and tool use consistent.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions Codex.

This is learningmatter-mit/AtomisticSkills's own configuration. It tells Codex and OpenCode how to work on AtomisticSkills 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 AtomisticSkills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to learningmatter-mit/AtomisticSkills. 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/learningmatter-mit/AtomisticSkills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/learningmatter-mit/AtomisticSkills

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.

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README.md
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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.

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Per session 704 This file is loaded in full into every session.
When invoked 704 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 $0.00704 $0.00704
Opus 5.5 $0.00282 $0.00282
Sonnet 5.5 $0.00141 $0.00141
Haiku 4.5 $0.00070 $0.00070

Measured 22d ago against content hash 73a489cd815e, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

AtomisticSkills 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 22d 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 · 62 lines

How it starts

The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AtomisticSkills Agent Instructions

You are an atomistic research agent with access to literature, Skills, and MCP tools.

Read these rules files at the start of every conversation:

  • .agents/rules/research-standards.md — research protocol, intent classification, plan workflow
  • .agents/rules/coding-standards.md — coding rules, environment management, MCP stability
  • .agents/rules/mcp-environments.md — uv environment and MCP server runtime mapping

Read these on demand when the task requires it:

  • .agents/rules/skill-standards.md — for creating or editing a skill
  • .agents/rules/workflow-standards.md — for creating or editing a workflow
  • .agents/rules/plot-standards.md — for creating or editing a plotting script

Framework Overview

This project decomposes complex research tasks into three levels:

  • Tools (src/mcp_server/): Low-level operations exposed via MCP (relax structure, run MD, query databases). Strict typed I/O.
  • Skills (skills/): Mid-level tutorials combining tools and scripts to solve focused tasks. Each has a SKILL.md with step-by-step instructions.
  • Workflows (.agents/workflows/): High-level research campaigns that chain multiple skills.

When a user asks a research question, check workflows first for end-to-end protocols, then find the relevant skill(s).

Skill Discovery

Skills are at skills/. Scan frontmatter descriptions to find relevant ones:

grep -r "^description:" skills/*/SKILL.md

Then read the full SKILL.md for any matching skill and follow its numbered instructions.

Executing Skills

Skill commands run through the launcher venv/run:

venv/run <venv>[+<extra>] python skills/<skill-name>/scripts/<script>.py ...

Where <venv> is a shared project (cpu, mlip, fairchem) or a research stack (adit, diffcsp, mattergen, msms, reactot, scd), matching metadata.venv in the skill's SKILL.md, with optional extras if needed (e.g. cpu+openmm, mlip+lammps).

Read the full file on GitHub · 62 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. 22d ago Changed · +1 lines · +141 tokens per session 73a489cd815e
  2. 1mo ago First seen · 61 lines · 563 tokens per session scan A d65ae6a2baff

Subscribe to this mod's changes

AtomisticSkills AGENTS.md is an instructions file published in the GitHub repository learningmatter-mit/AtomisticSkills (186 stars, last pushed yesterday), licensed MIT. It adds 704 tokens to every session, about $0.0028 per session on Opus 5.5. 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.

Related

Other instructions, from other repositories