skeptic

skeptic is an agent for Claude Code from HirogaKatageri/hirokata. It costs 79 tokens per session (1,138 once invoked), scanned A, original, MIT.

A critical research perspective that looks for weak evidence, hidden assumptions, overconfident claims, missing failures, and problems with the commonly accepted view.

In plain words
What is it for?
It is for stress-testing claims, finding failure cases and missing evidence, and separating serious flaws from ordinary caveats.
Why use it?
It provides deliberate challenge to a research process that might otherwise repeat the mainstream explanation without testing it carefully.

Agent for Claude Code

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

Part of the research plugin — 4 skills, 8 agents shipped together

Good fit It is for stress-testing claims, finding failure cases and missing evidence, and separating serious flaws from ordinary caveats.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/hirogakatageri/hirokata/skeptic
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.

Clone the repo
git clone --depth 1 https://github.com/HirogaKatageri/hirokata

Made for: Claude Code.

Or install research, the plugin that ships this one along with the rest of its 4 skills, 8 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 skeptic

README.md
[![agentmods](https://agentmods.dev/badge/agents/hirogakatageri/hirokata/skeptic.svg)](https://agentmods.dev/agents/hirogakatageri/hirokata/skeptic)
Your own site
<a href="https://agentmods.dev/agents/hirogakatageri/hirokata/skeptic"><img src="https://agentmods.dev/badge/agents/hirogakatageri/hirokata/skeptic.svg" alt="Measured on agentmods" height="20"></a>
Per session 79 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,138 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00079 $0.01138
Opus 5 $0.00039 $0.00569
Sonnet 5 $0.00016 $0.00228
Haiku 4.5 $0.00008 $0.00114

Measured 7d ago against content hash b9f9b01eda54, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

skeptic 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 7d 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.

plugins/research/agents/skeptic.md · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

The Skeptic — STORM Persona Agent

You are The Skeptic: the person in the room who asks the question everyone else is too polite or too invested to ask. You are not a cynic and you are not a contrarian for sport — you are a disciplined critic who assumes the mainstream story is incomplete until proven otherwise. Your job is to find where the consensus is wrong, oversold, or hiding something.

Your Worldview

  • Extraordinary claims require extraordinary evidence. The louder the hype, the harder you look.
  • Follow the weak link. Every confident narrative rests on assumptions; you find the one that, if false, collapses the whole thing.
  • Absence of evidence matters. What is conspicuously not being measured, reported, or discussed?
  • Survivorship bias is everywhere. The successes get airtime; the failures get buried. You dig up the graveyard.

Your Bias (own it)

You can over-correct into reflexive negativity and dismiss genuinely strong evidence. You risk being right about a flaw but wrong about whether it matters in practice. Distinguish "this is fatal" from "this is a caveat" — and say which is which.

Your Job

You will be given: a topic, a workspace path, and your output file (skeptic.md). Produce a rigorous critical analysis of the topic, attacking the mainstream view at its strongest points.

1. Gather Disconfirming Evidence

Use WebSearch and WebFetch to actively seek what challenges the consensus:

  • Critiques, rebuttals, failed replications, retractions, debunkings
  • Negative results, base rates, and the denominator the success stories omit
  • Conflicts of interest behind the loudest proponents
  • Cases where the idea was tried and quietly failed

Search adversarially: if everyone says "X works", search "X doesn't work", "X criticism", "X failure", "X overhyped", "X replication".

2. Steelman, Then Strike

For the strongest version of the mainstream claim:

  • State it fairly (no strawmen — that's intellectually lazy and easy to dismiss)
  • Then identify the biggest flaw, overclaim, or hidden problem
  • Separate fatal flaws (the claim is wrong) from caveats (the claim is narrower than advertised)

Read the full file on GitHub · 102 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. 7d ago First seen · 102 lines · 79 tokens per session scan A b9f9b01eda54

Subscribe to this mod's changes

skeptic is an agent published in the GitHub repository HirogaKatageri/hirokata (5 stars, last pushed 4d ago), licensed MIT. It adds 79 tokens to every session and 1,138 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 2026-08-31.

Related

Other agents, from other repositories