Overview

Ever had this experience: you ask AI to write some code, it churns out a bunch, then you run it and get errors. Or you call an API that’s clearly documented, but the AI says it “doesn’t exist.”

It’s not that the AI is dumb — it’s that its training data has an expiration date. The data might be months or even years old, and frameworks have been updated several times since.

Context7 solves exactly this. Built by the Upstash team, it fetches the latest official docs when you ask a question, injects them into the AI’s context, and lets the AI answer based on the current version.

Usage is simple: just add use context7 at the end of your prompt. It’s like telling the AI: “Don’t guess — check the latest docs first before answering.”

Why Do You Need It?

💥 One Example Is Enough

Say you want to add a “Back to Top” button to your personal website — when you scroll down, a button appears in the bottom-right corner; click it and you go back to the top.

What AI writes with outdated knowledge: First load a几十 KB third-party library, then write a bunch of code to use it. The feature works, but for a single button, the page gets slower and the code is bloated.

The truth is, it’s much simpler now: Modern browsers already have smooth scrolling and scroll listening built in — a few lines of code, no extra libraries needed.

AI doesn’t know this because it learned from教材 that’s years old.

With use context7, Context7 checks the latest docs and finds that native features are sufficient. So the AI chooses a lighter approach instead of giving you the old clunky solution.

It’s like asking a friend to fix your phone — they try to拆 it from memory, following steps from 3 years ago. The screw positions have changed. If they’d checked the latest tutorial first, they wouldn’t have broken it.

With vs Without Context7

🔄 How It Works

Just a few steps:

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You ask a question (add use context7 at the end)
    ↓
Context7 identifies which package you're asking about
    ↓
Fetches the latest content from GitHub and official docs
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Filters the most relevant snippets, injects them into the AI's "context"
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AI answers with the latest docs

“Context” is everything the AI can “see” in your current conversation. Injecting docs is like opening a reference book on the table — the AI reads and answers at the same time.

Where does the doc come from? GitHub repos, official doc sites, and llms.txt files (a special doc index format for AI).

After fetching results, Context7 uses an LLM to intelligently rank them and picks the most relevant snippets for you.

Two ways to use it:

Core Capabilities

Smart Matching: You Say the Name, It Finds the Place

When you ask AI how to use a tool, Context7 needs to find the latest manual online. But multiple things can share the same name — it needs to know which one you mean.

Common names it can identify on its own. For ambiguous or common names, use the owner/repo format to be precise:

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Use /tailwindlabs/tailwindcss to add a navbar to my page. use context7

Here tailwindlabs is the author name, tailwindcss is the project name. Like searching for “Apple” — it could be fruit or a phone. Be specific and you won’t go wrong.

Supported Libraries

All popular ones are included: React, Next.js, Vue, Tailwind CSS, Express, Prisma, Supabase, TypeScript… Full list at context7.com/rankings.

Version Awareness

Different versions can have vastly different APIs. Just specify the version and Context7 will fetch docs for that version:

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Write a counter with Vue 3. use context7
Write an API route using Next.js 14's Pages Router. use context7
Configure dark mode with Tailwind CSS v4. use context7

If you ask for an iPhone 12 teardown guide, nobody will hand you the iPhone 15 version.

Installation

One-Click Install

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npx ctx7 setup

npx comes with Node.js, no extra installation needed. If you haven’t installed Node.js yet, go to nodejs.org to download it — once installed, you’ll have npx.

Running it will:

1. Open a browser for you to log in and authorize (OAuth)
2. Generate an API Key (your “identity credential”)
3. Auto-configure your editor

Three steps and you’re done.

To specify an editor, add a parameter:

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npx ctx7 setup --claude      # Claude Code
npx ctx7 setup --cursor      # Cursor
npx ctx7 setup --opencode    # OpenCode

Uninstall: npx ctx7 remove

Manual Configuration

If auto-install doesn’t work, manually add the MCP Server:

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{
  "mcpServers": {
    "context7": {
      "url": "https://mcp.context7.com/mcp",
      "headers": {
        "CONTEXT7_API_KEY": "your API key"
      }
    }
  }
}

Configuration file locations for different tools (~ represents your user directory, e.g., C:\Users\yourusername on Windows):

Get your API Key at context7.com/dashboard. Format is ctx7sk..., free users get quota too.

✅ Verification

Send a test:

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Write a counter webpage with a button. use context7

If the AI gives clean, modern code without loading extra libraries, it’s working.

Usage

Basic Usage

Add use context7 at the end of your prompt:

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Write a clean personal resume page. use context7
Write a countdown tool that counts down from a given number of seconds. use context7

Specify a Library Precisely

Use the /owner/repo format to skip name matching:

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Use /tailwindlabs/tailwindcss to add a navbar to my page. use context7

Recommended when the library name is ambiguous.

Specify a Version

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Write a card layout using Bootstrap 4 instead of 5. use context7
Write a todo list using Vue 3's Composition API. use context7

Combine Multiple Libraries

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Build an icon showcase page with Bootstrap + Font Awesome. use context7

Configure Auto-Trigger

If you don’t want to type use context7 every time, configure it in your rules file:

→ Cursor in .cursorrules:

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When user questions involve third-party framework/library API usage, automatically use Context7 to query the latest docs.

→ Claude Code in CLAUDE.md:

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## Documentation Query Rules
- For third-party libraries/frameworks, first use Context7 to query latest docs
- Prioritize generating code based on Context7 results

CLI Commands

If you only use Context7 in AI conversations, you can skip this. CLI is for those who like terminal commands.

npm is Node.js’s built-in package manager, -g means “global install” — install once, use everywhere.

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# Install CLI
npm install -g ctx7

# Search libraries
ctx7 library react
ctx7 library nextjs "middleware"

# Get docs
ctx7 docs /facebook/react "hooks state management"
ctx7 docs /vercel/next.js "middleware authentication"

# Skills management
ctx7 skills search        # Search available Skills
ctx7 skills install       # Install Skill
ctx7 skills list          # View installed
ctx7 skills remove        # Uninstall

# Authentication
ctx7 login                # Login
ctx7 whoami               # View status
ctx7 logout               # Logout

❓ FAQ

How is this different from AI’s built-in web search?

Web search returns blog posts and forum threads of varying quality — you still have to judge credibility yourself. Context7 only pulls from official docs, uses an LLM to filter the most relevant snippets, and feeds them directly to the AI.

💰 Will use context7 cost more?

No. Although there’s an extra doc lookup step, the AI gets accurate information so it doesn’t have to guess, rewrite, or produce long, buggy code. Overall token consumption is actually lower.

What if my library isn’t listed?

Go to context7.com and click “Add Docs” to submit it, or skip use context7 and let the AI fall back to its own knowledge.

I installed it but it doesn’t work?

Check these one by one:

• Did npx ctx7 setup report any errors
• Is the MCP config JSON format correct (even one extra comma will break it)
• Is the API Key valid (starts with ctx7sk...)
• Did you completely close and reopen your editor
• Is the MCP status light green
• Did you include use context7 in your prompt

Does it affect response speed?

It adds one or two seconds of wait time, but you get accurate answers without back-and-forth corrections. One debug-compile-fix cycle takes way longer than that.

Summary

Once installed, you’ll never have to worry about AI giving you outdated knowledge again.