magi

A decision-review system that splits a question among three viewpoints: scientific reasoning, safety and user impact, and practical judgment. It runs these reviews in parallel and checks one result against evidence.

In plain words
What is it for?
Use it to review technical designs, tests, architecture, data safety, compatibility, usability, and team impact.
Why use it?
It helps expose trade-offs and overlooked risks before choosing an approach.

Skill for Claude CodeCodex

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/float1122/magi-system/magi
Any agent
npx skills add float1122/magi-system --skill magi
Clone the repo
git clone --depth 1 https://github.com/float1122/magi-system

Made for: Claude Code, Codex.

Per session 151 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 975 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00151 $0.00975
Opus 5 $0.00076 $0.00487
Sonnet 5 $0.00030 $0.00195
Haiku 4.5 $0.00015 $0.00097

Measured 2d ago against content hash 4aae3b74fd6d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

magi 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 2d 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.

magi/SKILL.md · 73 lines

How it starts

The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MAGI — Distributed Judgment Trinity

On invocation, the MAGI system awakens. The three cores align.

        質問              解決

CODE:473
FILE:MAGI_SYS    BALTHASAR•2(◦◦◦◦◦)
EXTENTION:3023          ╱─╲
EX_MODE:OFF   CASPER•3(◦◦◦)─MAGI─MELCHIOR•1(◦◦◦◦)
PRIORITY:AAA           ╲─╱

The Three Cores

MELCHIOR (과학자의 논리) — Empirical truth, performance, architecture, testing. Rigorous, evidence-based, asks "does this actually work?"

BALTHASAR (모성의 보호) — Safety, user impact, data integrity, backward compatibility. Protective, consequence-aware, asks "what harm could result?"

CASPER (개인의 직관) — Pragmatism, usability, team sustainability, aesthetics. Intuitive, direct veto power, asks "does this feel right?"

Core Law: Sub-Agent-Forced

The orchestrator NEVER judges. It only:

  1. Decomposes the request into Core-specific judgment nodes (10–20 total, 3–5 per Core)
  2. Dispatches 3 Core subagents in parallel, each with self-contained briefs
  3. Verifies ONE fact from the results with your own hands (read, test, measure)
  4. Reports voting outcome and next steps

Each Core recursively breaks its judgment into variable-sized nodes, self-verifies each node, then submits a composite verdict.

Voting

Regular decisions: 2/3 majority (any 2 Cores agree).

Grave ops (file deletion, prod deploy, DB drop, force-push, auth/payment bypass, security system disable): 3/3 unanimity required. Any Core may VETO. One veto = BLOCKED.

Node states: OK (▪), DELIBERATING (▨), COMPROMISED (▓). Only OK nodes contribute to the vote.

Scale Gate

Trivial decisions (one-line question, naming/style tweak, single simple choice) → Don't use MAGI. Answer directly or use a targeted skill. MAGI is overkill and wastes context.

Regular decisions (feature addition, refactor, API change) → 2/3 majority. Use MAGI.

Grave ops (irreversible, destructive, breaking app flows) → 3/3 unanimity + veto. Use MAGI with caution.

Lower bound: If the question takes <2 minutes to decide solo, don't invoke MAGI. Ask yourself first.

Read the full file on GitHub · 73 lines

Files

What ships with it

3 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. 2d ago First seen · 73 lines · 0 tokens per session scan A 4aae3b74fd6d

Subscribe to this mod's changes

magi is a skill published in the GitHub repository float1122/magi-system (9 stars, last pushed 2mo ago), licensed MIT. It adds 151 tokens to every session and 975 once invoked, about $0.0008 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 2026-08-31.

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