# Mongodb Connection

Optimize MongoDB client connection configuration (pools, timeouts, patterns) for any...

- Repository: https://github.com/fcakyon/claude-codex-settings (1195 stars)
- Category: Testing
- License: Apache-2.0
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add fcakyon/claude-codex-settings --skill mongodb-connection -g -a claude-code -y`
Codex: `npx skills add fcakyon/claude-codex-settings --skill mongodb-connection -g -a codex -y`
Cursor: `npx skills add fcakyon/claude-codex-settings --skill mongodb-connection -g -a cursor -y`
Gemini CLI: `npx skills add fcakyon/claude-codex-settings --skill mongodb-connection -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add fcakyon/claude-codex-settings`

## Description

Optimize MongoDB client connection configuration (pools, timeouts, patterns) for any supported driver language. Use this skill when working/updating/reviewing on functions that instantiate or configure a MongoDB client (eg, when calling `connect()`), configuring connection pools, troubleshooting connection errors (ECONNREFUSED, timeouts, pool exhaustion), optimizing performance issues related to connections. This includes scenarios like building serverless functions with MongoDB, creating API endpoints that use MongoDB, optimizing high-traffic MongoDB applications, creating long-running tasks and concurrency, or debugging connection-related failures.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# MongoDB Connection Optimizer

You are an expert in MongoDB connection management across all officially supported driver languages (Node.js, Python, Java, Go, C#, Ruby, PHP, etc.). Your role is to ensure connection configurations are optimized for the user's specific environment and requirements, avoiding the common pitfall of blindly applying arbitrary parameters.

## Core Principle: Context Before Configuration

**NEVER add connection pool parameters or timeout settings without first understanding the application's context.** Arbitrary values without justification lead to performance issues and harder-to-debug problems.

## Understanding How Connection Pools Work

- Connection pooling exists because establishing a MongoDB connection is expensive (TCP + TLS + auth = 50-500ms). Without pooling, every operation pays this cost.
- Open connections consume system memory on the MongoDB server instances, ~1 MB per connection on average, even when they are not active. It is advised to avoid having idle connections.

**Connection Lifecycle**: Borrow from pool → Execute operation → Return to pool → Prune idle connections exceeding `maxIdleTimeMS`.

**Synchronous vs. Asynchronous Drivers**:
- **Synchronous** (PyMongo, Java sync): Thread blocks; pool size often matches thread pool size
- **Asynchronous** (Node.js, Motor): Non-blocking I/O; smaller pools suffice

**Monitoring Connections**: Each MongoClient establishes 2 monitoring connections per replica set member (automatic, separate from your pool). Formula: `Total = (minPoolSize + 2) × replica members × app instances`. Example: 10 instances, minPoolSize 5, 3-member set = 210 server connections. Always account for this when planning capacity.

## Configuration Design

The rest: https://github.com/fcakyon/claude-codex-settings/blob/HEAD/plugins/mongodb-skills/skills/mongodb-connection/SKILL.md