demo-3-uv-mcp-implementation

demo-3-uv-mcp-implementation is a cursor rule for Cursor from SwonVIP/mcp-server-talk. It costs 0 tokens per session (941 once invoked), scanned A, original, MIT.

A demo of an MCP server built with Python and uv, a tool for managing Python projects and dependencies. It provides mathematical tools, information resources, and reusable prompts for an MCP client.

In plain words
What is it for?
Use it to demonstrate calculations through MCP, create a Python project with uv, configure Cursor to run the server, and provide example resources and prompts.
Why use it?
It gives you a ready example of the files and configuration needed for a uv-based MCP server. It also documents handling errors such as division by zero and invalid square roots.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it to demonstrate calculations through MCP, create a Python project with uv, configure Cursor to run the server, and provide example resources and prompts.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation
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.

Clone the repo
git clone --depth 1 https://github.com/SwonVIP/mcp-server-talk

Made for: Cursor.

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-3-uv-mcp-implementation

README.md
[![agentmods](https://agentmods.dev/badge/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation/github.svg)](https://agentmods.dev/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation)
Your own site
<a href="https://agentmods.dev/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation"><img src="https://agentmods.dev/badge/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation/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-3-uv-mcp-implementation

Your own site · 80×15
<a href="https://agentmods.dev/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation"><img src="https://agentmods.dev/badge/rules/swonvip/mcp-server-talk/demo-3-uv-mcp-implementation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 941 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.
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 $0.00000 $0.00941
Opus 5 $0.00000 $0.00470
Sonnet 5 $0.00000 $0.00188
Haiku 4.5 $0.00000 $0.00094

Measured 8d ago against content hash a3e1f4e51272, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

demo-3-uv-mcp-implementation 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 8d 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.

.cursor/rules/demo-3-uv-mcp-implementation.mdc · 140 lines

How it starts

The opening of the file, as written. The whole thing — 140 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Demo 3: UV-Based MCP Server Implementation

Implementation Checklist

✅ Core Files Created

  • demo/3/simple_mcp_server.py - Main MCP server implementation
  • demo/3/pyproject.toml - UV project configuration
  • demo/3/README.md - Comprehensive documentation
  • demo/3/DEMO_GUIDE.md - Quick demo guide
  • demo/3/setup.sh - Setup and utility script
  • demo/3/cursor_mcp_config.json - Sample Cursor configuration
  • demo/3/.gitignore - Git ignore rules

✅ MCP Server Features

  • Mathematical tools (add, subtract, multiply, divide, power, sqrt, factorial, percentage, average)
  • Resources (server-info, recipe content)
  • Prompts (math-helper, calculator)
  • Error handling for edge cases (division by zero, negative square roots, etc.)
  • FastMCP framework integration

✅ UV Integration

  • Proper pyproject.toml configuration
  • Python 3.10+ requirement (FastMCP compatibility)
  • Simplified package structure (script-only, no build system)
  • Dependency management with UV
  • Virtual environment creation

✅ Cursor Configuration

  • Sample MCP configuration file
  • Absolute path handling
  • UV command structure for MCP clients
  • Documentation for configuration steps

✅ Documentation

  • Comprehensive README with setup instructions
  • Demo guide with step-by-step instructions
  • Troubleshooting section
  • Comparison with Docker version
  • File structure documentation

✅ Testing & Validation

  • UV sync functionality verified
  • Server startup testing
  • Dependency resolution confirmed
  • Setup script functionality

Key Implementation Decisions

UV Configuration

  • Used simplified pyproject.toml without build system
  • Focused on dependency management only
  • Avoided package building complexity
  • Used Python 3.10+ for FastMCP compatibility

Read the full file on GitHub · 140 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. 8d ago First seen · 140 lines · 0 tokens per session scan A a3e1f4e51272

Subscribe to this mod's changes

demo-3-uv-mcp-implementation is a cursor rule published in the GitHub repository SwonVIP/mcp-server-talk (0 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 941 tokens. 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.