one-three-one-rule

one-three-one-rule is a skill for Claude Code, Codex from chemany/Mente. It costs 105 tokens per session (1,067 once invoked), scanned A, a copy of one-three-one-rule, MIT.

A decision-making format for comparing technical approaches: one problem statement, three options, and one recommended plan.

In plain words
What is it for?
Use it when selecting an approach, tool, migration path, or design and you need a concise recommendation that can be shared with a team.
Why use it?
It turns a choice involving architecture, tools, or refactoring into a consistent comparison with explicit trade-offs.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

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/chemany/mente/one-three-one-rule
Any agent
npx skills add chemany/Mente --skill one-three-one-rule
Clone the repo
git clone --depth 1 https://github.com/chemany/Mente

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 one-three-one-rule

README.md
[![agentmods](https://agentmods.dev/badge/skills/chemany/mente/one-three-one-rule.svg)](https://agentmods.dev/skills/chemany/mente/one-three-one-rule)
Your own site
<a href="https://agentmods.dev/skills/chemany/mente/one-three-one-rule"><img src="https://agentmods.dev/badge/skills/chemany/mente/one-three-one-rule.svg" alt="Measured on agentmods" height="20"></a>
Per session 105 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,067 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 83% copy Near-identical to another mod 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 $0.00105 $0.01067
Opus 5 $0.00053 $0.00534
Sonnet 5 $0.00021 $0.00213
Haiku 4.5 $0.00011 $0.00107

Measured 6d ago against content hash a4de46b4da5a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

one-three-one-rule 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.

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

This is a copy

83% identical to one-three-one-rule — 10 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

optional-skills/communication/one-three-one-rule/SKILL.md · 104 lines

How it starts

The opening of the file, as written. The whole thing — 104 lines — stays where its author put it; the contents beside it link to each section on GitHub.

1-3-1 Communication Rule

Structured decision-making format for when a task has multiple viable approaches and the user needs a clear recommendation. Produces a concise problem framing, three options with trade-offs, and an actionable plan for the recommended path.

When to Use

  • The user explicitly asks for a "1-3-1" response.
  • The user says "give me options" or "what are my choices" for a technical decision.
  • A task has multiple viable approaches with meaningful trade-offs (architecture, tooling, migration strategy).
  • The user needs a proposal they can forward to a team or stakeholder.

Do NOT use for simple questions with one obvious answer, debugging sessions, or tasks where the user has already decided on an approach.

Procedure

  1. Problem (one sentence)

    • State the core decision or desired outcome in a single concise sentence.
    • Focus on the what, not the how — no implementation details, tool names, or specific technologies.
    • Keep it tight. If you need "and", you're describing two problems.
  2. Options (exactly three)

    • Present three distinct, viable approaches labeled A, B, C.
    • Each option gets a brief description, pros, and cons.
    • Options should represent genuinely different strategies, not minor variations of the same approach.
  3. Recommendation (one option)

    • State which option you recommend and why, based on the user's context and priorities.
    • Be direct — this is your professional judgment, not a hedge.
  4. Definition of Done

    • List the specific success criteria for the recommended option.
    • These are concrete, verifiable outcomes — not vague aspirations.
    • If the user picks a different option, revise this section to match.
  5. Implementation Plan

    • Concrete steps to execute the recommended option.
    • Include specific commands, tools, or actions where applicable.
    • If the user picks a different option, revise this section to match.

Verification

  • Response has exactly one Problem sentence.
  • Response has exactly three Options (A, B, C) with pros and cons for each.
  • Response has a single Recommendation that picks one option with reasoning.
  • Definition of Done and Implementation Plan align with the recommended option.
  • If the user selects a different option, Recommendation, DoD, and Implementation Plan update accordingly.

Read the full file on GitHub · 104 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. 6d ago First seen · 104 lines · 105 tokens per session scan A a4de46b4da5a

Subscribe to this mod's changes

one-three-one-rule is a skill published in the GitHub repository chemany/Mente (11 stars, last pushed 3mo ago), licensed MIT. It adds 105 tokens to every session and 1,067 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. It is 83% identical to one-three-one-rule, differing in 10 lines, and is treated as a copy.

Related

Other skills, from other repositories

release-announcement

Write a release announcement — changelog, blog post, in-app note, or social post — that leads with user impact, names the audience, and includes upgrade/migration steps without filler.

paperclipai/paperclip · 42 tokens

one-three-one-rule

1-3-1 decision briefs: problem, three options, one pick.

NousResearch/hermes-agent · 21 tokens

simplified-english

Write user-facing comments, plans, and documents in ASD-STE100 Simplified Technical English — short, unambiguous sentences with approved words and one meaning each — so readers understand them the first time.

paperclipai/paperclip · 46 tokens

response-compression

Compresses verbose responses by removing filler and framing to save 200-400 tokens. Use when responses feel bloated or context is filling fast.

athola/claude-night-market · 33 tokens

novu-inbox-integration

Integrate Novu's in-app notification inbox into web applications. Supports React, Next.js, and vanilla JavaScript. Includes the Inbox component (bell icon + notification feed), composable components (Bell, Notifications, InboxContent, Preferences), headless hooks, branded theming, custom render props, multi-tenancy…

novuhq/novu · 111 tokens

novu-design-workflow

Design notification workflows the Novu way — choose channels, set severity, decide when a workflow is critical, configure digests, and route based on subscriber state. Applies to BOTH dashboard-authored and code-first (@novu/framework) workflows. Use when planning a new workflow, deciding which channels to include…

novuhq/novu · 114 tokens