vahtian: Skill for Claude Code

.claude/skills/run-vahtian/SKILL.md

run-vahtian is a skill for Claude Code from heidihelena/vahtian. It costs 130 tokens per session (1,702 once invoked), scanned B, original, Apache-2.0.

A local preview tool for Vahtian’s static website, which is made of plain HTML pages. It serves product pages as they would appear online and captures desktop and mobile screenshots.

In plain words
What is it for?
Use it to launch, preview, build, or screenshot Vahtian’s homepage and product pages, including CiteVahti, StudyVahti, and ReviewVahti.
Why use it?
It lets you inspect the rendered page instead of guessing from HTML source. It also handles clean page URLs and missing-page responses like the live site.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: reads .claude/ paths.

This is heidihelena/vahtian's own configuration. It tells Claude Code how to work on vahtian itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything vahtian configures →

Reuse

Borrowing it

Nothing to install: this file belongs to heidihelena/vahtian. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/heidihelena/vahtian/main/.claude/skills/run-vahtian/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/heidihelena/vahtian

Made for: Claude Code.

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 run-vahtian

README.md
[![agentmods](https://agentmods.dev/badge/skills/heidihelena/vahtian/run-vahtian/github.svg)](https://agentmods.dev/skills/heidihelena/vahtian/run-vahtian)
Your own site
<a href="https://agentmods.dev/skills/heidihelena/vahtian/run-vahtian"><img src="https://agentmods.dev/badge/skills/heidihelena/vahtian/run-vahtian/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for run-vahtian

Your own site · 80×15
<a href="https://agentmods.dev/skills/heidihelena/vahtian/run-vahtian"><img src="https://agentmods.dev/badge/skills/heidihelena/vahtian/run-vahtian.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 130 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,702 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. 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 $0.00130 $0.01702
Opus 5 $0.00065 $0.00851
Sonnet 5 $0.00026 $0.00340
Haiku 4.5 $0.00013 $0.00170

Measured 12d ago against content hash 838e3a16695b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade B, and why

run-vahtian scanned grade B with 1 finding 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 12d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (driver.mjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Enumerates other installed skillsmediumAgent snooping

Other skills' SKILL.md files reveal prompts, capabilities and secrets that should be invisible to peers.

- `Cannot find Playwright` → run `cd .claude/skills/run-vahtian && npm install
.claude/skills/run-vahtian/SKILL.md · 127 lines

How it starts

The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Run Vahtian

Vahtian's site is plain static HTML — one index.html per product, deployed via Cloudflare (wrangler.jsonc: assets.directory = "."). There is no build step, no framework, no bundler, no trackers. You don't "start" it so much as serve the directory.

The agent path is the driver: .claude/skills/run-vahtian/driver.mjs. It starts a tiny static server that resolves clean URLs the way Cloudflare does (/studyvahti/studyvahti/index.html, unknown → 404.html), then drives it with Playwright's bundled headless Chromium and writes desktop + mobile screenshots. Use it whenever you need to see the rendered page — every UX or copy change should be looked at, not inferred from HTML source.

All paths below are relative to the repo root (<unit>/ = the vahtian/ repo).

Prerequisites

  • Node (any recent version; the container pins 22 via .node-version, Heidi's Mac runs 20 — both work).
  • Playwright. The driver resolves it from the first place it exists:
    1. the skill's own node_modules (macOS path — installed once with cd .claude/skills/run-vahtian && npm install; gitignored),
    2. the container's global install at /opt/node22/lib/node_modules/playwright.

First-time setup on a new machine:

cd .claude/skills/run-vahtian && npm install playwright

Browser binaries live in a separate cache (~/Library/Caches/ms-playwright on macOS) and are usually already there; if launch fails with Executable doesn't exist, run npx playwright install chromium (this one is a large download — avoid on slow connections unless needed).

Run (agent path) — the driver

# Screenshot the default set (home + the four live product pages),
# desktop (1280×900) and mobile (390×844):
node .claude/skills/run-vahtian/driver.mjs

# Screenshot specific paths only:
node .claude/skills/run-vahtian/driver.mjs / /studyvahti /reviewvahti

# Status check only (serve + assert every path returns 200, no browser):
node .claude/skills/run-vahtian/driver.mjs --check / /studyvahti /llms.txt

Read the full file on GitHub · 127 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. 12d ago First seen · 127 lines · 130 tokens per session scan B 838e3a16695b

Subscribe to this mod's changes

run-vahtian is a skill published in the GitHub repository heidihelena/vahtian (1 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 130 tokens to every session and 1,702 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 1 finding (enumerates other installed skills). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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