mcp-test-harness

mcp-test-harness is a skill for Claude Code, Codex from LLMTooling/cloudscraper-mcp-server. It costs 94 tokens per session (1,244 once invoked), scanned A, original, no licence file.

A testing workflow for MCP servers, which connect AI assistants to tools and data. It creates automated integration tests using pytest for Python, Vitest for TypeScript, or MCP Inspector for general testing.

In plain words
What is it for?
Use it to test MCP servers over STDIO, create Python or TypeScript integration tests, and run checks with the MCP Inspector command-line tool.
Why use it?
It helps verify that an MCP server works across its real communication interface instead of relying only on isolated unit tests.

Skill for Claude CodeCodex

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 skills/llmtooling/cloudscraper-mcp-server/mcp-test-harness
Any agent
npx skills add LLMTooling/cloudscraper-mcp-server --skill mcp-test-harness
Clone the repo
git clone --depth 1 https://github.com/LLMTooling/cloudscraper-mcp-server

Made for: Claude Code, Codex.

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 mcp-test-harness

README.md
[![agentmods](https://agentmods.dev/badge/skills/llmtooling/cloudscraper-mcp-server/mcp-test-harness.svg)](https://agentmods.dev/skills/llmtooling/cloudscraper-mcp-server/mcp-test-harness)
Your own site
<a href="https://agentmods.dev/skills/llmtooling/cloudscraper-mcp-server/mcp-test-harness"><img src="https://agentmods.dev/badge/skills/llmtooling/cloudscraper-mcp-server/mcp-test-harness.svg" alt="Measured on agentmods" height="20"></a>
Per session 94 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,244 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 $0.00094 $0.01244
Opus 5 $0.00047 $0.00622
Sonnet 5 $0.00019 $0.00249
Haiku 4.5 $0.00009 $0.00124

Measured 4d ago against content hash cd23e092c3f9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mcp-test-harness 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 4d ago.

The scan reads SKILL.md. This mod also ships 4 executable files (assets/python/conftest.py, assets/python/test_mcp_template.py, assets/typescript/mcp-server.test.ts, …), 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.

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.

.claude/skills/mcp-test-harness/SKILL.md · 140 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 4d ago First seen · 140 lines · 94 tokens per session scan A cd23e092c3f9

Subscribe to this mod's changes

mcp-test-harness is a skill published in the GitHub repository LLMTooling/cloudscraper-mcp-server (1 stars, last pushed 3mo ago), with no licence file. It adds 94 tokens to every session and 1,244 once invoked, about $0.0005 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.

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