by Aspegio
Organisation for Claude Code inspired by time-tested Royal Navy operating procedures.
# Add to your Claude Code skills
git clone https://github.com/Aspegio/nelsonLast scanned: 5/26/2026
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}nelson is an open-source ai agents skill for AI coding assistants such as Claude Code, Codex CLI, and ChatGPT, built by Aspegio. Organisation for Claude Code inspired by time-tested Royal Navy operating procedures. It has 402 GitHub stars.
Yes. nelson passed SkillsLLM's automated security scan — a dependency vulnerability audit plus prompt-injection heuristics — with no high-severity issues. You can read the full report in the Security Report section on this page.
Clone the repository with "git clone https://github.com/Aspegio/nelson" and add it to your Claude Code skills directory (see the Installation section above).
nelson is primarily written in Python. It is open-source under Aspegio on GitHub, so you can review or fork the full source.
Yes. SkillsLLM lists many other AI Agents skills you can browse and compare side by side. Open the AI Agents category from the badge at the top of this page, or use the Related Skills and comparison links further down to weigh nelson against similar tools.
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If you believe that what works well for people works well for agents, there's few finer examples of organisational tradition than the Royal Navy to base the rules on. This framework does just that, for Claude Code.
4 risk tiers · 11 damage control procedures · 11 mission templates · 7 crew roles · 16 standing orders
Install the plugin:
/plugin marketplace add harrymunro/nelson
/plugin install nelson@nelson-marketplace
Describe your mission — Nelson loads automatically, no slash command needed:
Use Nelson to migrate the payment module from Stripe v2 to v3
Nelson will draft sailing orders, present a battle plan for your approval, form a squadron of captains to execute in parallel, run quarterdeck checkpoints, and produce a captain's log when the mission stands down. See Prerequisites for the full agent-team experience with split panes.
https://github.com/user-attachments/assets/2468679d-39f5-4efb-9d93-43d43eee8907
Nelson gives Claude an eight-step operational framework for tackling complex missions:
Most agent orchestration tools focus on starting missions. Nelson focuses on completing them safely.
Nelson gives your missions a shared vocabulary: "action stations" instead of "risk tier escalation", "hull integrity" instead of "context window consumption", "man overboard" instead of "stuck agent replacement". The names stick. So do the habits.
Nelson coordinates its own development — recent releases have been planned and executed as Nelson missions.
It may be overkill if you're doing a quick, single-file edit.
Nelson trades upfront setup time for coordination guarantees:
| Approach | Best when | Trade-off |
|---|---|---|
| Nelson Navy structure | You need repeatable quality gates, explicit ownership, and a clear decision log across parallel work | More setup and coordination overhead up front |
| OmO/RuFlo-style rapid flow | You need the fastest possible movement on a narrow, low-risk path | Less formal checkpointing and role separation |
If you need fast parallel execution with minimal ceremony, OmO or RuFlo may suit you better. If coordination, auditability, and safe scaling matter more than raw tempo, Nelson is the better fit.
The skill selects one of five execution modes based on your mission:
| Mode | When to use | How it works |
|---|---|---|
single-session |
Sequential tasks, low complexity, heavy same-file editing | Claude works through tasks in order within one session |
subagents |
Parallel tasks where workers only report back to the coordinator | Claude spawns subagents that work independently and return results |
agent-team |
Parallel tasks where workers need to coordinate with each other | Claude creates an agent team with direct teammate-to-teammate communication |
workflow |
Large fan-out audits, repeatable migrations, codebase-wide analysis, or cross-checked research | Nelson writes a Workflow Charter and verification contract for one approved dynamic workflow run |
hybrid-workflow |
Workflow-suitable missions that need probes, Station 2/3 controls, or human approval between stages | Nelson gates a sequence of separate workflow runs, reviewing telemetry and outputs before the next stage |
Claude Code dynamic workflows move orchestration into workflow scripts that can fan out to many agents, keep intermediate results in script state, and aggregate broad review or migration results. Nelson does not replace that mechanism. Nelson wraps it with doctrine: Sounding-the-Channel probes, explicit permission gates, cost guardrails, audit logs, and verification contracts before findings or edits are accepted.
ultracode is treated as a Claude Code xhigh effort/automation setting, not a Nelson execution mode. If ultracode or the user chooses a workflow, Nelson still supplies the mission charter, risk tiering, human gates, telemetry expectations, and fallback mode.
For long autonomous, headless, or scheduled runs, Nelson aligns with Claude Code's /goal — a session-scoped Stop hook that keeps the session from stopping until a completion condition is met. Nelson composes the condition from the sailing orders (nelson-data.py goal-condition) so it stays tied to the mission's outcome, metric, and stop criteria, and phrases it against what the goal evaluator can actually see: the conversation transcript. The standing goal and Nelson's Mission Complete Gate reinforce each other — the gate is the discipline the admiral applies, the goal is the harness backstop that enforces it. See references/goal-alignment.md.
Nelson uses a three-tier hierarchy. The admiral coordinates captains, each captain commands a named ship, and crew members aboard each ship do the specialist work.
┌───────────┐
│ Admiral │
└─────┬─────┘
┌─────────────┼─────────────┐
▼ ▼ ▼
┌───────────┐ ┌───────────┐ ┌───────────┐
│ Captain │ │ Captain │ │ Red-Cell │
│ HMS Daring │ │ HMS Kent │ │ Navigator │
└─────┬─────┘ └─────┬─────┘ └───────────┘
┌────┼────┐ ┌────┼────┐
▼ ▼ ▼ ▼ ▼ ▼
XO PWO MEO PWO NO COX
Squadron level:
Ship level (crew per captain, 0-4 members):
| Role | Abbr | Function | When to crew |
|---|---|---|---|
| Executive Officer | XO | Integration & orchestration | 3+ crew or interdependent sub-tasks |
| Principal Warfare Officer | PWO | Core implementation | Almost always (default doer) |
| Navigating Officer | NO | Codebase research & exploration | Unfamiliar code, large codebase |
| Marine Engineering Officer | MEO | Testing & validation | Station 1+ or non-trivial verification |
| Weapon Engineering Officer | WEO | Config, infrastructure & systems integration | Significant config/infra work |
| Logistics Officer | LOGO | Documentatio |