How to use the Backend Patterns Node.js API agent skill

What the backend-patterns skill makes the agent do

An agent skill is a set of instructions that an AI agent loads when a task matches it. The backend-patterns skill is instructional text with code examples. When it is active, the agent follows the patterns in its guide when you ask it to design or review Node.js, Express or Next.js API routes and their data access.

The guide covers RESTful URL design, the repository, service and controller layers, middleware for auth and error handling, avoiding N+1 queries, selecting only the columns you need, Redis cache-aside, and centralised error handling. The skill does not run anything itself. It shapes the code the agent writes and the advice it gives.

Install the backend-patterns skill

Download the ZIP file for the skill from its page on this directory, then unzip it. The skill folder contains two files: SKILL.md, which holds the instructions, and agents/openai.yaml.

For a personal setup, put the unzipped skill folder inside ~/.claude/skills/. To limit it to one project, put it inside that project's .claude/skills/ folder instead.

If you use the Claude apps, you can upload the ZIP instead. Open Settings, go to Capabilities, then find Skills and upload the file there.

• Personal install: ~/.claude/skills/ (available across your projects)
• Project install: .claude/skills/ inside the project folder (available only there)
• Claude apps: Settings → Capabilities → Skills (upload the ZIP)

Trigger the skill with natural requests

You do not need a special command. The skill's description says it applies when you are building or reviewing Node.js, Express or Next.js API routes and their data access, so ask for that work in ordinary words. Name the framework and the goal so the agent can match the request to the skill.

Requests that fit well include designing an endpoint, moving code into repository and service layers, speeding up a slow query, adding a cache, writing auth middleware, or reviewing an existing route for error handling.

• Design a REST endpoint for listing and updating markets in my Next.js API routes.
• Review this Express route for N+1 queries and suggest fixes.
• Split this controller into repository, service and controller layers.
• Add Redis cache-aside to the market lookup in my Node.js backend.
• Write auth middleware and a centralised error handler for my Express API.

Examples of patterns the skill applies

For endpoint design, the skill uses resource-based URLs with filters, sorting and pagination in the query string. For example, a list request might look like the line below.

For database work, it prefers selecting only the columns you need instead of selecting everything, and it batch-fetches related records instead of querying once per row. For caching, it shows a Redis cache-aside pattern: check the cache first, fall back to the database on a miss, then store the result with a time to live. For errors, it shows a central handler that returns a consistent JSON shape and a 500 response for unexpected errors.

What you need before you use it

The skill needs a Node.js project. Its examples assume Express or Next.js API routes and are written in TypeScript. The Supabase client and a Redis client are optional, but only needed if you follow those specific examples.

If your backend uses another language or framework, the patterns will not map directly, and the skill is not a fit for you. The skill is licensed under MIT.

• A Node.js project using Express or Next.js API routes
• TypeScript familiarity to read and adapt the examples
• Optional: a Supabase client and a Redis client, if you follow those examples

Safety notes: scripts and network access

This skill runs no scripts and uses no network access. It only provides instructions and examples for the agent to follow.

The examples are illustrative, not production-ready. Some are incomplete. The vector search method in the service layer is a placeholder with no implementation. The Supabase transaction function relies on a comment saying the rollback happens automatically, so test that behaviour yourself before relying on it. Review all generated code before it reaches production.

• Runs scripts: no
• Uses network: no
• Placeholder code: the vector search method in the service example has no body
• Verify the Supabase transaction example's rollback behaviour before trusting it

Tips for getting good results

Give the agent your real context: the framework, the database client, and the file you want changed. The skill's advice is general, so the more specific your request, the more useful the adaptation will be.

Ask the agent to review your existing code against the skill rather than only generating new code. Patterns such as N+1 prevention and column selection are easiest to apply to code that already exists.

• Name your framework (Express or Next.js API routes) in every request
• Paste the existing route or query so the agent can review it
• Ask for tests or a review step before copying snippets into production