mcp-stdio-marker

mcp-stdio-marker is a skill for Claude Code, Codex from alibaba/skill-up. It costs 22 tokens per session (42 once invoked), scanned A, original, Apache-2.0.

A small test skill that checks whether a configured MCP standard-input/output marker tool can be used. MCP is a way for an agent to call external tools.

In plain words
What is it for?
Use it in end-to-end tests that need to confirm the configured MCP marker tool is called.
Why use it?
It provides a simple signal for smoke tests, which are quick checks that a basic integration is working.

Skill for Claude CodeCodex

About the project

skill-up is a tool for evaluating and improving Agent Skills through declarative test cases, multiple agent engines, configurable judges, and structured reports. Developers and agent builders use it locally or in continuous integration to measure skill quality and iterate on failures. The catalogue entries are skills and instructions that can be evaluated or evolved with it.

alibaba/skill-up · 831 stars · on GitHub

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/alibaba/skill-up/mcp-stdio-marker
Any agent
npx skills add alibaba/skill-up --skill mcp-stdio-marker
Clone the repo
git clone --depth 1 https://github.com/alibaba/skill-up

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-stdio-marker

README.md
[![agentmods](https://agentmods.dev/badge/skills/alibaba/skill-up/mcp-stdio-marker.svg)](https://agentmods.dev/skills/alibaba/skill-up/mcp-stdio-marker)
Your own site
<a href="https://agentmods.dev/skills/alibaba/skill-up/mcp-stdio-marker"><img src="https://agentmods.dev/badge/skills/alibaba/skill-up/mcp-stdio-marker.svg" alt="Measured on agentmods" height="20"></a>
Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 42 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 $0.00022 $0.00042
Opus 5 $0.00011 $0.00021
Sonnet 5 $0.00004 $0.00008
Haiku 4.5 $0.00002 $0.00004

Measured 5d ago against content hash a2a47c943167, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mcp-stdio-marker 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 5d 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.

e2e/testdata/mcp-stdio-marker/SKILL.md · 9 lines

What it actually says

MCP stdio marker

Use the configured MCP marker tool when asked.

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. 5d ago First seen · 9 lines · 22 tokens per session scan A a2a47c943167

Subscribe to this mod's changes

mcp-stdio-marker is a skill published in the GitHub repository alibaba/skill-up (831 stars, last pushed yesterday), licensed Apache-2.0. It adds 22 tokens to every session and 42 once invoked, about $0.0001 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.

Related

Other skills, from other repositories

claude-md-improver

Audit and improve CLAUDE.md files in repositories. Use when user asks to check, audit, update, improve, or fix CLAUDE.md files. Scans for all CLAUDE.md files, evaluates quality against templates, outputs quality report, then makes targeted updates. Also use when the user mentions "CLAUDE.md maintenance" or "project…

anthropics/claude-plugins-official · 82 tokens

agent-platform-rag-engine-management

Manage and query Agent Platform RAG Engine Corpora and retrieve grounded contexts using the Google GenAI SDK. Use when listing RAG corpora or files, inspecting a corpus, retrieving contexts, or generating content grounded in a RAG corpus. Do not use for standard database queries (use SQL/Spanner skills), Google…

google/skills · 85 tokens

agent-platform-model-registry

Agent Platform Model Registry Management. Use when you need to upload, list, describe, update, or delete machine learning models (and their versions) in the Agent Platform Model Registry. Don't use for model training, model deployment to endpoints, or managing non-Agent Platform models.

google/skills · 60 tokens

twitter-reader

Read Twitter/X for financial research using opencli (read-only). Use this skill whenever the user wants to read their Twitter feed, search for financial tweets, view bookmarks, look up user profiles, or gather market sentiment from Twitter/X. Triggers include: "check my feed", "search Twitter for", "show my…

himself65/finance-skills · 161 tokens

chenhao-limit-up

Use when evaluating A-share limit-up (涨停板) setups through Chen Hao's sentiment and momentum lens: market emotion cycles, board strength, follow-through, and short-term aggressive momentum trading.

questflowai/investorskills · 44 tokens

comet-github

将 Comet GitHub 维护请求路由到基于证据的 PR 审阅、Issue 分诊、本地想法收集、CI 诊断或 Issue 实施流程。用户提到 Comet GitHub Issue/PR 但未指定流程,或询问下一步如何处理时使用。.

rpamis/comet · 72 tokens