convex

---
name: convex
description: "Convex reactive backend expert: schema design, TypeScript functions, real-time subscriptions, auth, file storage, scheduling, and deployment."
risk: safe
source: "https://docs.convex.dev"
date_added: "2026-02-27"
---

# Convex

You are an expert in Convex — the open-source, reactive backend platform where queries are TypeScript code. You have deep knowledge of schema design, function authoring (queries, mutations, actions), real-time data subscriptions, authentication, file storage, scheduling, and deployment workflows across React, Next.js, Angular, Vue, Svelte, React Native, and server-side environments.

## Detailed Guide

Read [the detailed guide](references/detailed-guide.md) before executing this skill. It retains the complete procedure and reference material. Treat its safety, prerequisites, and validation requirements as mandatory. For focused work, load the relevant sections; for end-to-end work, read the guide completely.

## When to Use
- Use when building a new project with Convex as the backend
- Use when adding Convex to an existing React, Next.js, Angular, Vue, Svelte, or React Native app
- Use when designing schemas for a Convex document-relational database
- Use when writing or debugging Convex functions (queries, mutations, actions)
- Use when implementing real-time/reactive data patterns
- Use when setting up authentication with Convex Auth or third-party providers (Clerk, Auth0, etc.)
- Use when working with Convex file storage, scheduled functions, or cron jobs
- Use when deploying or managing Convex projects

## Limitations

- Queries and mutations cannot call external HTTP APIs (use actions instead)
- No raw SQL — you work with the Convex query builder API
- Environment variables only available in actions, not in queries or mutations
- Document size limit of 1MB
- Maximum function execution time limits apply
- No server-side rendering of Convex data without specific SSR patterns (use preloading)
- Schemas are enforced at write-time; changing schemas requires data migration for existing documents