demo

demo is a skill for Claude Code from masanami/claude-harness. It costs 71 tokens per session (2,417 once invoked), scanned B, original, no licence file.

A browser-based walkthrough that uses Playwright, a tool for controlling web browsers, to check whether an application works. A successful walkthrough can be turned into an end-to-end test, which checks a complete user journey.

In plain words
What is it for?
Use it to demonstrate application flows, verify them in a browser, and create end-to-end tests from successful scenarios.
Why use it?
It lets a user watch and approve an application check while preserving successful scenarios as repeatable tests.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter. Also seen: model in frontmatter.

Part of the claude-harness plugin — 23 skills, 22 agents, 1 hook shipped together

Good fit Use it to demonstrate application flows, verify them in a browser, and create end-to-end tests from successful scenarios.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/masanami/claude-harness/demo
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.

Any agent
npx skills add masanami/claude-harness --skill demo
Clone the repo
git clone --depth 1 https://github.com/masanami/claude-harness

Made for: Claude Code.

Or install claude-harness, the plugin that ships this one along with the rest of its 23 skills, 22 agents, 1 hook.

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 demo

README.md
[![agentmods](https://agentmods.dev/badge/skills/masanami/claude-harness/demo/github.svg)](https://agentmods.dev/skills/masanami/claude-harness/demo)
Your own site
<a href="https://agentmods.dev/skills/masanami/claude-harness/demo"><img src="https://agentmods.dev/badge/skills/masanami/claude-harness/demo/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 demo

Your own site · 80×15
<a href="https://agentmods.dev/skills/masanami/claude-harness/demo"><img src="https://agentmods.dev/badge/skills/masanami/claude-harness/demo.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 71 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,417 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 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 $0.00071 $0.02417
Opus 5 $0.00036 $0.01208
Sonnet 5 $0.00014 $0.00483
Haiku 4.5 $0.00007 $0.00242

Measured 9d ago against content hash 70705fc4a2ad, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade B, and why

demo 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 9d ago.

The scan reads SKILL.md. This mod also ships 3 executable files (scripts/lib/parse-pause-ms.mjs, scripts/run-walkthrough.mjs, scripts/walkthrough-setup.sh), 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.

Asks for rootmediumPrivilege escalation

A mod that escalates privileges can change anything on the machine, not only the project.

- `deps-missing` の場合、スクリプトは **sudo を勝手に実行せず**、必要なコマンド(例: `sudo <playwright> install-deps chromium`)を表示して正常終了する。
skills/demo/SKILL.md · 118 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 9d ago First seen · 118 lines · 71 tokens per session scan B 70705fc4a2ad

Subscribe to this mod's changes

demo is a skill published in the GitHub repository masanami/claude-harness (5 stars, last pushed 3d ago), with no licence file. It adds 71 tokens to every session and 2,417 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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