trotter

trotter is a skill for Claude Code, Codex from unitarylab/quantum-practices. It costs 58 tokens per session (4,730 once invoked), scanned A, original, no licence file.

A method for simulating how a quantum system changes over time under a Hamiltonian, an operator that describes its energy or dynamics. It approximates the evolution e^{-iHt} by multiplying together many shorter, structured exponential steps.

In plain words
What is it for?
Use it to construct, run, debug, and validate Trotter-Suzuki Hamiltonian simulations with chosen orders and step counts.
Why use it?
It replaces a difficult full matrix exponential with a controllable approximation whose accuracy depends on the formula order and number of steps.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

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/unitarylab/quantum-practices/trotter
Any agent
npx skills add unitarylab/quantum-practices --skill trotter
Clone the repo
git clone --depth 1 https://github.com/unitarylab/quantum-practices

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 trotter

README.md
[![agentmods](https://agentmods.dev/badge/skills/unitarylab/quantum-practices/trotter.svg)](https://agentmods.dev/skills/unitarylab/quantum-practices/trotter)
Your own site
<a href="https://agentmods.dev/skills/unitarylab/quantum-practices/trotter"><img src="https://agentmods.dev/badge/skills/unitarylab/quantum-practices/trotter.svg" alt="Measured on agentmods" height="20"></a>
Per session 58 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,730 The whole file, excluding the scripts and references it only reads on demand.
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 5.1 $0.00058 $0.04730
Opus 5 $0.00029 $0.02365
Sonnet 5 $0.00012 $0.00946
Haiku 4.5 $0.00006 $0.00473

Measured 6d ago against content hash 0ef1c387a295, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

trotter 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.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/algorithm.py, scripts/trotter_implementation.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

algorithms/hamiltonian-simulation/trotter/SKILL.md · 406 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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 · 406 lines · 58 tokens per session scan A 0ef1c387a295

Subscribe to this mod's changes

trotter is a skill published in the GitHub repository unitarylab/quantum-practices (18 stars, last pushed 22d ago), with no licence file. It adds 58 tokens to every session and 4,730 once invoked, about $0.0003 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.