nelson: Instructions file for Codex

AGENTS.md

nelson AGENTS.md is an instructions file for Codex, OpenCode from Aspegio/nelson. It costs 128 tokens per session, scanned A, original, MIT.

Repository instructions for Nelson, a Claude Code skill that coordinates agent work through an eight-step process using Royal Navy terminology. It points to the project structure and overview documents.

In plain words
What is it for?
Use them when organizing multi-step agent work, consulting project structure, following the Nelson operating process, and checking maintainability sensors.
Why use it?
They give an agent a defined sequence for planning and coordinating work, along with places to learn the repository layout and maintainability checks.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions CLAUDE.md; mentions Claude Code.

This is Aspegio/nelson's own configuration. It tells Codex and OpenCode how to work on nelson 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 nelson configures →

Reuse

Borrowing it

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

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 nelson AGENTS.md

README.md
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Your own site
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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.

agentmods 80×15 button for nelson AGENTS.md

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Per session 128 This file is loaded in full into every session.
When invoked 128 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 $0.00128 $0.00128
Opus 5.5 $0.00051 $0.00051
Sonnet 5.5 $0.00026 $0.00026
Haiku 4.5 $0.00013 $0.00013

Measured 1mo ago against content hash 4dd7f7cea0d8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

nelson 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 1mo 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.

AGENTS.md · 13 lines

What it actually says

Nelson

Nelson is a Claude Code skill for coordinating agent work using Royal Navy terminology. It provides an eight-step operational framework: Sailing Orders, The Estimate, Battle Plan, Form the Squadron, Get Permission to Sail, Quarterdeck Rhythm, Action Stations, and Stand Down.

Key references

Maintainability sensors

See CLAUDE.md → Maintainability sensors for the full sensor reference.

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. 1mo ago First seen · 13 lines · 128 tokens per session scan A 4dd7f7cea0d8

Subscribe to this mod's changes

nelson AGENTS.md is an instructions file published in the GitHub repository Aspegio/nelson (423 stars, last pushed 3mo ago), licensed MIT. It adds 128 tokens to every session, about $0.0005 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 2026-08-30.

Related

Other instructions, from other repositories