reviewer

reviewer is an agent for Claude Code from btseytlin/ultrapack. It costs 86 tokens per session (1,512 once invoked), scanned A, original, WTFPL.

An independent code-review agent that checks a task against its plan, rules that must remain true, and stated assumptions. It looks at decisions from the viewpoint of the developer who will maintain the code later.

In plain words
What is it for?
Use it to audit completed or proposed changes, rank findings by severity, and report only findings meeting its confidence threshold.
Why use it?
It helps find design problems and future maintenance risks that may be missed when reviewing only whether the immediate task works.

Agent for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: model in frontmatter.

Part of the up plugin — 18 skills, 6 commands, 6 agents shipped together

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 agents/btseytlin/ultrapack/reviewer
Clone the repo
git clone --depth 1 https://github.com/btseytlin/ultrapack

Made for: Claude Code.

Or install up, the plugin that ships this one along with the rest of its 18 skills, 6 commands, 6 agents.

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 reviewer

README.md
[![agentmods](https://agentmods.dev/badge/agents/btseytlin/ultrapack/reviewer.svg)](https://agentmods.dev/agents/btseytlin/ultrapack/reviewer)
Your own site
<a href="https://agentmods.dev/agents/btseytlin/ultrapack/reviewer"><img src="https://agentmods.dev/badge/agents/btseytlin/ultrapack/reviewer.svg" alt="Measured on agentmods" height="20"></a>
Per session 86 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,512 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin unknown 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 $0.00086 $0.01512
Opus 5 $0.00043 $0.00756
Sonnet 5 $0.00017 $0.00302
Haiku 4.5 $0.00009 $0.00151

Measured 6d ago against content hash b8c6ea4d1ee9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

reviewer 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.

agents/reviewer.md · 112 lines

The source is not reproduced here

Licensed WTFPL

The repository is licensed WTFPL, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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 · 112 lines · 86 tokens per session scan A b8c6ea4d1ee9

Subscribe to this mod's changes

reviewer is an agent published in the GitHub repository btseytlin/ultrapack (47 stars, last pushed 1mo ago), licensed WTFPL. It adds 86 tokens to every session and 1,512 once invoked, about $0.0004 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 2026-08-30.