arena

arena is a command for coding agents from sifxprime/kodelyth-ecc. It costs 35 tokens per session (1,456 once invoked), scanned A, original, MIT.

An adversarial code-hardening workflow in which one side builds or fixes code and another side tries to break it. Verified findings are sent back for fixes, and the rounds stop when attacks stop finding anything new or the limits are reached.

In plain words
What is it for?
Use it to harden code such as payment webhooks, find security issues, verify those findings, and apply fixes across repeated rounds.
Why use it?
It exposes weaknesses through repeated attack and verification before the code is shipped, while tracking accepted findings and resource limits.

Command

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 commands/sifxprime/kodelyth-ecc/arena
Clone the repo
git clone --depth 1 https://github.com/sifxprime/kodelyth-ecc

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 arena

README.md
[![agentmods](https://agentmods.dev/badge/commands/sifxprime/kodelyth-ecc/arena.svg)](https://agentmods.dev/commands/sifxprime/kodelyth-ecc/arena)
Your own site
<a href="https://agentmods.dev/commands/sifxprime/kodelyth-ecc/arena"><img src="https://agentmods.dev/badge/commands/sifxprime/kodelyth-ecc/arena.svg" alt="Measured on agentmods" height="20"></a>
Per session 35 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,456 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 $0.00035 $0.01456
Opus 5 $0.00017 $0.00728
Sonnet 5 $0.00007 $0.00291
Haiku 4.5 $0.00003 $0.00146

Measured yesterday against content hash 91a3fa613aa7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

arena 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 yesterday.

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.

commands/arena.md · 137 lines

How it starts

The opening of the file, as written. The whole thing — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/arena — GOD vs EVIL, until the attacker gives up

The two crews fight over your code. GOD builds and hardens. EVIL attacks and tries to break it. Verified findings go back to GOD. Repeat until two consecutive rounds surface nothing new — then you ship, knowing an adversary already tried and failed.

This is the expensive one. ~200k tokens per round (GOD ≈ 90k + EVIL ≈ 96k + verification). Defaults are 3 rounds / 400k tokens, and the budget guard aborts before overspending. Use /god-mode or /evil-mode alone when you don't need the full loop.

The loop

round N:  GOD builds/fixes  →  EVIL hunts  →  EVIL verifies  →  close round
                                                                    │
                          converged? out of budget? out of rounds? ─┤
                                    no → round N+1                  │
                                                                   yes → report

Convergence = the win condition. Not "zero findings" — findings may remain open and accepted. It means attacking harder stopped yielding anything new.

Usage

/arena harden the payment webhook
/arena add rate limiting --scope src/api --max-rounds 2
/arena prepare this repo for open-source --all

Start and inspect from the terminal:

kodelythecc arena start --task "harden the webhook" --scope src/ --max-rounds 3
kodelythecc arena next <run-id>          # what the loop wants next (JSON)
kodelythecc arena report <run-id> --md   # full markdown report
kodelythecc arena list

Instructions to the assistant

0. Start the run

kodelythecc arena start --task "<goal>" --scope "<path>" [--max-rounds N]

Capture the run id. Every step below is driven by:

kodelythecc arena next <run-id>

which returns the next action, its briefs, and a token estimate. Follow it — do not improvise the order.

1. god_build

Run the GOD-mode stages from the action's stages array (see /god-mode). Round 1 builds; later rounds fix what EVIL proved — those findings arrive in the brief as mandatory work items.

Read the full file on GitHub · 137 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. yesterday First seen · 137 lines · 35 tokens per session scan A 91a3fa613aa7

Subscribe to this mod's changes

arena is a command published in the GitHub repository sifxprime/kodelyth-ecc (11 stars, last pushed 2d ago), licensed MIT. It adds 35 tokens to every session and 1,456 once invoked, about $0.0002 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 2026-09-03.