jupyter-mcp-server: Skill for Claude Code

.github/skills/code-review/SKILL.md

code-review is a skill for Claude Code, Codex from datalayer/jupyter-mcp-server. It costs 62 tokens per session (1,774 once invoked), scanned A, original, BSD-3-Clause.

A code-review guide for changes to Jupyter MCP Server, a service that lets an agent read and run Jupyter notebooks.

In plain words
What is it for?
Use it when reviewing pull requests or diffs in this repository. It helps check tests, documentation, protocol behavior, and the result format of new tools.
Why use it?
It focuses review on quiet defects, such as tests that pass without checking the intended code or documentation that describes behavior the code does not implement.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

This is datalayer/jupyter-mcp-server's own configuration. It tells Claude Code and Codex how to work on jupyter-mcp-server 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 jupyter-mcp-server configures →

About the project

Jupyter MCP Server is a Model Context Protocol server that lets AI agents connect to and manage Jupyter notebooks in real time. It supports notebooks running locally or on hosted platforms, and its catalogue add-ons provide commands and skills for working with those notebooks.

datalayer/jupyter-mcp-server · 1,315 stars · on GitHub · jupyter-mcp-server.datalayer.tech

Reuse

Borrowing it

Nothing to install: this file belongs to datalayer/jupyter-mcp-server. 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/datalayer/jupyter-mcp-server/main/.github/skills/code-review/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/datalayer/jupyter-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 code-review

README.md
[![agentmods](https://agentmods.dev/badge/skills/datalayer/jupyter-mcp-server/code-review/github.svg)](https://agentmods.dev/skills/datalayer/jupyter-mcp-server/code-review)
Your own site
<a href="https://agentmods.dev/skills/datalayer/jupyter-mcp-server/code-review"><img src="https://agentmods.dev/badge/skills/datalayer/jupyter-mcp-server/code-review/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 code-review

Your own site · 80×15
<a href="https://agentmods.dev/skills/datalayer/jupyter-mcp-server/code-review"><img src="https://agentmods.dev/badge/skills/datalayer/jupyter-mcp-server/code-review.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 62 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,774 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00062 $0.01774
Opus 5.5 $0.00025 $0.00710
Sonnet 5.5 $0.00012 $0.00355
Haiku 4.5 $0.00006 $0.00177

Measured 2mo ago against content hash 2a80e33d9d7b, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

code-review 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 2mo 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.

.github/skills/code-review/SKILL.md · 154 lines

How it starts

The opening of the file, as written. The whole thing — 154 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Reviewing a change to Jupyter MCP Server

This server is what an agent talks to when it reads and runs somebody's notebooks. Most of what goes wrong here is quiet: a test that passes without exercising its subject, a tool that answers an empty list instead of an error, a page that documents a flag nothing reads. None of it fails loudly, and all of it has happened.

Review for those first. Ordinary bugs are usually caught by the suite.

Start here: does the test exercise its subject?

The most common defect in this repository is not broken code — it is a test that passes for a reason other than the one it claims. Two real examples:

  • test_an_expired_task_is_gone… called store.get() before store.list(). get() deletes the expired record itself, so by the time list() ran there was nothing left to sweep and the sweep never executed. list() was iterating a dictionary while popping from it — a guaranteed RuntimeError — and the test named after that path was green.
  • tests/test_mcpb_version_sync.py never ran at all. It imports scripts.sync_mcpb_version, scripts/ had no __init__.py, and the module failed at collection. The suite was green and the version drift it guards was unguarded.

So for every new or changed test, ask:

  • Would it fail if the behaviour were removed? If you cannot say yes, delete the assertion or strengthen it. Say so in the review.
  • Does an earlier line already do the work? A setup call that cleans up, caches, or short-circuits leaves the code under test unreached.
  • Does it assert a cell, or a substring of everything? assert "no" in output passes on almost any English. Pull the row or the field apart.
  • Does it signal by raising inside a try? Several functions here catch Exception deliberately — a test that raises to signal gets swallowed and asserts nothing. Record into a list and assert the list.
  • Does it set an environment variable that was already read at import? config-style modules read once. Patch the attribute, not the environment.

Read the full file on GitHub · 154 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. 2mo ago First seen · 154 lines · 62 tokens per session scan A 2a80e33d9d7b

Subscribe to this mod's changes

code-review is a skill published in the GitHub repository datalayer/jupyter-mcp-server (1,315 stars, last pushed 2d ago), licensed BSD-3-Clause. It adds 62 tokens to every session and 1,774 once invoked, about $0.0002 per session on Opus 5.5. 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

trace-mcp-refactoring

Safe refactoring workflow using trace-mcp — assess risk, find candidates, check impact, and rename symbols across all files without missing import sites or cross-file references.

nikolai-vysotskyi/trace-mcp · 39 tokens

frontmcp-development

Use when building any FrontMCP server component other than a tool (for tools, use create-tool). Covers @Resource static resources and parameterized URI templates; @Prompt reusable prompts (RAG, multi-turn); @Provider singleton dependency-injection providers (database pools, API clients); @Agent autonomous LLM agents…

agentfront/frontmcp · 196 tokens

zen-review

Expert code reviewer. Analyze PR changes for correctness, security, performance, and quality. Returns findings as JSON. CRITICAL: this skill is costly, don't use it unless user explicitly requested to use it.

EliasOulkadi/shokunin · 44 tokens

git-workflow

Follow this team's Git conventions for branching, commit messages, and pull requests.

modelcontextprotocol/csharp-sdk · 19 tokens

m1nd-first

Use when investigating a repository, searching for implementation, reviewing changes, working from specs/docs, or preparing a risky code change in an environment where m1nd is available. This doctrine makes m1nd the first investigative layer before grep, glob, or manual file reads, except when the task is pure…

maxkle1nz/m1nd · 78 tokens

review-thread

Record review verdicts and run the StateNote review thread on an agent-operation instance — every ReviewRequest verdict is one atomic batch-direct-write that advances status and co-writes a reviewnote explaining why, and findings are corrected by appending notes rather than editing them.

cruxible-ai/cruxible · 56 tokens