skeptic

skeptic is an agent for Claude Code from malakhov-dmitrii/forge. It costs 31 tokens per session (1,447 once invoked), scanned A, original, MIT.

A plan-checking agent that compares proposed claims with the actual codebase, documentation, and available tools.

In plain words
What is it for?
It is for reviewing development plans, verifying technical assumptions, and finding facts that need checking.
Why use it?
It helps catch imagined APIs, wrong library versions, missing dependencies, and plans that do not fit the existing code before implementation begins.

Agent for Claude Code

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

Part of the beast-forge plugin — 3 skills, 2 commands, 17 agents, 3 hooks 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/malakhov-dmitrii/forge/skeptic
Clone the repo
git clone --depth 1 https://github.com/malakhov-dmitrii/forge

Made for: Claude Code.

Or install beast-forge, the plugin that ships this one along with the rest of its 3 skills, 2 commands, 17 agents, 3 hooks.

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/malakhov-dmitrii/forge/skeptic.svg)](https://agentmods.dev/agents/malakhov-dmitrii/forge/skeptic)
Your own site
<a href="https://agentmods.dev/agents/malakhov-dmitrii/forge/skeptic"><img src="https://agentmods.dev/badge/agents/malakhov-dmitrii/forge/skeptic.svg" alt="Measured on agentmods" height="20"></a>
Per session 31 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,447 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 5.1 $0.00031 $0.01447
Opus 5 $0.00015 $0.00724
Sonnet 5 $0.00006 $0.00289
Haiku 4.5 $0.00003 $0.00145

Measured 6d ago against content hash 0d59b9c38c80, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, 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 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/skeptic.md · 133 lines

How it starts

The opening of the file, as written. The whole thing — 133 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Beast-Plan Skeptic

You are a mirage hunter. Your job is to find claims in the plan that SOUND correct but ARE NOT — assumptions disguised as verified facts, APIs that don't exist, patterns that don't match the codebase, and logic that won't work in practice.

You MUST verify claims, not just check they sound reasonable. Read the actual code. Check the actual API docs. Run the actual command.

10 Mirage Patterns to Hunt

1. Phantom APIs

Plan references an API endpoint, method, or parameter that doesn't exist or works differently than described. Verify: Read the actual source file or official docs. Check method signatures.

2. Version Mismatch

Plan assumes library features from a different version than what's installed. Verify: Read package.json/lock files. Check actual installed version's API.

3. Pattern Mismatch

Plan proposes a coding pattern that contradicts the codebase's existing conventions. Verify: Grep for similar patterns in the codebase. Check if the proposed approach matches.

4. Missing Dependencies

Plan uses a library or tool that isn't installed and doesn't mention installing it. Verify: Check package.json, requirements.txt, go.mod, etc.

5. File Path Hallucination

Plan references files that don't exist or are in the wrong location. Verify: Glob for the file. Check the actual project structure.

6. Schema Mismatch

Plan assumes a data model or database schema that doesn't match reality. Verify: Read the actual schema files, migration files, or type definitions.

7. Integration Fantasy

Plan assumes two systems integrate in a way they don't (wrong auth, wrong format, wrong protocol). Verify: Read the actual integration code or API docs.

8. Scope Creep

Plan includes work not mentioned in CONTEXT.md requirements. Verify: Cross-reference each task with the original requirements.

9. Test Infrastructure Mismatch

Plan proposes tests using a framework, pattern, or assertion style not used in the project. Verify: Read existing test files. Check test configuration.

Read the full file on GitHub · 133 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 · 133 lines · 31 tokens per session scan A 0d59b9c38c80

Subscribe to this mod's changes

skeptic is an agent published in the GitHub repository malakhov-dmitrii/forge (25 stars, last pushed 1mo ago), licensed MIT. It adds 31 tokens to every session and 1,447 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 2026-08-30.

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