How to integrate Open sea MCP with Claude Code

Manage your Open sea directly from Claude Code with zero worries about OAuth hassles, API-breaking issues, or reliability and security concerns. You can do this in two different ways: Via Composio Connect - Direct and easiest approach Via Composio SDK - Programmatic approach with more control

Open sea logoOpen sea
Api Key

OpenSea is the world's first and largest NFT marketplace for digital collectibles and crypto assets. Instantly buy, sell, and explore NFTs across blockchains, all in one place.

24 Tools

Introduction

Manage your Open sea directly from Claude Code with zero worries about OAuth hassles, API-breaking issues, or reliability and security concerns.

You can do this in two different ways:

  1. Via Composio Connect - Direct and easiest approach
  2. Via Composio SDK - Programmatic approach with more control

Also integrate Open sea with

Why use Composio?

  • Only one MCP URL to connect multiple apps with Claude Code with zero auth hassles.
  • Programmatic tool calling allows LLMs to write its code in a remote workbench to handle complex tool chaining. Reduces to-and-fro with LLMs for frequent tool calling.
  • Handling Large tool responses out of LLM context to minimize context rot.
  • Dynamic just-in-time access to 20,000 tools across 1000+ other Apps for cross-app workflows. It loads the tools you need, so LLMs aren't overwhelmed by tools you don't need.

Connecting Open sea to Claude Code using Composio

1. Add the Composio MCP to Claude

Terminal

2. Start Claude Code

bash
claude

3. Open your MCP list

bash
/mcp

4. Select Composio and click on Authenticate

Select Composio and click Authenticate

5. This will redirect you to the Composio OAuth page. Complete the flow by authorizing Composio and you're all set.

Composio OAuth authorization page
Composio authorization complete
Ask Claude to connect to your account and authenticate via the link

What is the Open sea MCP server, and what's possible with it?

The Open sea MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your OpenSea account. It provides structured and secure access to your NFT marketplace activity, so your agent can perform actions like listing NFTs for sale, creating and fulfilling offers, checking account details, and managing your marketplace orders on your behalf.

  • NFT listing automation: Quickly list any ERC721 or ERC1155 NFT for sale on OpenSea, specifying price and collection details—all handled by your agent.
  • Offer creation and management: Instruct your agent to create criteria-based or single-item offers to purchase specific NFTs or those matching certain traits within a collection.
  • Order and listing fulfillment: Let your agent retrieve all necessary information and signatures to fulfill existing listings or offers, making transactions seamless and secure.
  • Marketplace activity insights: Have the agent pull your profile details, fetch all active listings or offers for a given collection, and provide you with up-to-date marketplace snapshots.
  • Order cancellation and management: Direct your agent to cancel open orders, listings, or offers off-chain, helping you stay in control of your marketplace participation with ease.

Connecting Open sea via Composio SDK

Composio SDK is the underlying tech that powers Rube. It's a universal gateway that does everything Rube does but with much more programmatic control. You can programmatically generate an MCP URL with the app you need (here Open sea) for even more tool search precision. It's secure and reliable.

How the Composio SDK works

The Composio SDK follows a three-phase workflow:

  1. Discovery: Searches for tools matching your task and returns relevant toolkits with their details.
  2. Authentication: Checks for active connections. If missing, creates an auth config and returns a connection URL via Auth Link.
  3. Execution: Executes the action using the authenticated connection.

Step-by-step Guide

Step by step10 STEPS
1

Prerequisites

Before starting, make sure you have:
  • Claude Pro, Max, or API billing enabled Anthropic account
  • Composio API Key
  • A Open sea account
  • Basic knowledge of Python or TypeScript
2

Install Claude Code

bash
# macOS, Linux, WSL
curl -fsSL https://claude.ai/install.sh | bash

# Windows PowerShell
irm https://claude.ai/install.ps1 | iex

# Windows CMD
curl -fsSL https://claude.ai/install.cmd -o install.cmd && install.cmd && del install.cmd

To install Claude Code, use one of the following methods based on your operating system:

3

Set up Claude Code

bash
cd your-project-folder
claude

Open a terminal, go to your project folder, and start Claude Code:

  • Claude Code will open in your terminal
  • Follow the prompts to sign in with your Anthropic account
  • Complete the authentication flow
  • Once authenticated, you can start using Claude Code
Claude Code initial setup showing sign-in prompt
Claude Code terminal after successful login
4

Set up environment variables

bash
COMPOSIO_API_KEY=your_composio_api_key_here
USER_ID=your_user_id_here

Create a .env file in your project root with the following variables:

  • COMPOSIO_API_KEY authenticates with Composio (get it from Composio dashboard)
  • USER_ID identifies the user for session management (use any unique identifier)
5

Install Composio library

npm install @composio/core dotenv

Install the Composio TypeScript library to create MCP sessions.

  • @composio/core provides the core Composio functionality
  • dotenv loads environment variables from your .env file
6

Generate Composio MCP URL

import 'dotenv/config';
import { Composio } from '@composio/core';

const { COMPOSIO_API_KEY, USER_ID } = process.env;

if (!COMPOSIO_API_KEY || !USER_ID) {
  throw new Error('COMPOSIO_API_KEY and USER_ID required in .env');
}

const composioClient = new Composio({ apiKey: COMPOSIO_API_KEY });

const composioSession = await composioClient.create(USER_ID, {
  toolkits: ['open_sea'],
});

const composioMcpUrl = composioSession?.mcp.url;

console.log(`MCP URL: ${composioMcpUrl}`);
console.log(`\nUse this command to add to Claude Code:`);
console.log(`claude mcp add --transport http open_sea-composio "${composioMcpUrl}" --headers "X-API-Key:${COMPOSIO_API_KEY}"`);

Create a script to generate a Composio MCP URL for Open sea. This URL will be used to connect Claude Code to Open sea.

What's happening

  • We import the Composio client and load environment variables
  • Create a Composio instance with your API key
  • Call create() to create a Tool Router session for Open sea
  • The returned mcp.url is the MCP server URL that Claude Code will use
  • The script prints this URL so you can copy it
7

Run the script and copy the MCP URL

node --loader ts-node/esm generate_mcp_url.ts
# or if using tsx
tsx generate_mcp_url.ts

Run your TypeScript script to generate the MCP URL.

  • The script connects to Composio and creates a Tool Router session
  • It prints the MCP URL and the exact command you need to run
  • Copy the entire claude mcp add command from the output
8

Add Open sea MCP to Claude Code

bash
claude mcp add --transport http open_sea-composio "YOUR_MCP_URL_HERE" --headers "X-API-Key:YOUR_COMPOSIO_API_KEY"

# Then restart Claude Code
exit
claude

In your terminal, add the MCP server using the command from the previous step. The command format is:

  • claude mcp add registers a new MCP server with Claude Code
  • --transport http specifies that this is an HTTP-based MCP server
  • The server name (open_sea-composio) is how you'll reference it
  • The URL points to your Composio Tool Router session
  • --headers includes your Composio API key for authentication

After running the command, close the current Claude Code session and start a new one for the changes to take effect.

9

Verify the installation

bash
claude mcp list

Check that your Open sea MCP server is properly configured.

  • This command lists all MCP servers registered with Claude Code
  • You should see your open_sea-composio entry in the list
  • This confirms that Claude Code can now access Open sea tools

If everything is wired up, you should see your open_sea-composio entry listed:

Claude Code MCP list showing the toolkit MCP server
10

Authenticate Open sea

The first time you try to use Open sea tools, you'll be prompted to authenticate.

  • Claude Code will detect that you need to authenticate with Open sea
  • It will show you an authentication link
  • Open the link in your browser (or copy/paste it)
  • Complete the Open sea authorization flow
  • Return to the terminal and start using Open sea through Claude Code

Once authenticated, you can ask Claude Code to perform Open sea operations in natural language. For example:

  • "List my NFT for sale on OpenSea"
  • "Show all active listings in Bored Ape collection"
  • "Create an offer for a specific CryptoPunk"

Complete Code

Here's the complete code to get you started with Open sea and Claude Code:

import 'dotenv/config';
import { Composio } from '@composio/core';

const { COMPOSIO_API_KEY, USER_ID } = process.env;

if (!COMPOSIO_API_KEY || !USER_ID) {
  throw new Error('COMPOSIO_API_KEY and USER_ID required in .env');
}

const composioClient = new Composio({ apiKey: COMPOSIO_API_KEY });

const composioSession = await composioClient.create(USER_ID, {
  toolkits: ['open_sea'],
});

const composioMcpUrl = composioSession?.mcp.url;

console.log(`MCP URL: ${composioMcpUrl}`);
console.log(`\nUse this command to add to Claude Code:`);
console.log(`claude mcp add --transport http open_sea-composio "${composioMcpUrl}" --headers "X-API-Key:${COMPOSIO_API_KEY}"`);

Conclusion

You've successfully integrated Open sea with Claude Code using Composio's MCP server. Now you can interact with Open sea directly from your terminal using natural language commands.

Key features of this setup:

  • Terminal-native experience without switching contexts
  • Natural language commands for Open sea operations
  • Secure authentication through Composio's managed MCP
  • Tool Router for dynamic tool discovery and execution

Next steps:

  • Try asking Claude Code to perform various Open sea operations
  • Add more toolkits to your Tool Router session for multi-app workflows
  • Integrate this setup into your development workflow for increased productivity

You can extend this by adding more toolkits, implementing custom workflows, or building automation scripts that leverage Claude Code's capabilities.

TOOLS

Supported Tools

Every Open sea action and event your agent gets out of the box.

Build criteria offer

Build a portion of a criteria offer including the merkle tree needed to post an offer.

Cancel order

Offchain cancel a single order, offer or listing, by its order hash when protected by the SignedZone.

Create criteria offer

Create a criteria offer to purchase any NFT in a collection or which matches the specified trait.

Create item offer

Create an offer to purchase a single NFT (ERC721 or ERC1155).

Create listing

List a single NFT (ERC721 or ERC1155) for sale on the OpenSea marketplace.

Fulfill listing

Retrieve all the information, including signatures, needed to fulfill a listing directly onchain.

Fulfill offer

Retrieve all the information, including signatures, needed to fulfill an offer directly onchain.

Get account

Get an OpenSea Account Profile including details such as bio, social media usernames, and profile image.

Get all listings by collection

Get all active, valid listings for a single collection.

Get all offers by collection

Get all active, valid offers for the specified collection.

Get best listing by nft

Get the best listing for an NFT.

Get best listings by collection

Get the cheapest priced active, valid listings on a single collection.

Get best offer by nft

Get the best offers for an NFT.

Get collection

Get a single collection including details such as fees, traits, and links.

Get collections

Get a list of OpenSea collections with optional filtering and pagination.

Get collection stats

Get stats for a single collection on OpenSea.

Get contract

Get a smart contract for a given chain and address.

Get events

Get a list of events from OpenSea based on various filters like timestamps and event types.

Get listings

Get the complete set of active, valid listings.

Get nft

Get metadata, traits, ownership information, and rarity for a single NFT.

Get order

Get a single order, offer or listing, by its order hash.

Get payment token

Get a smart contract for a given chain and address.

Get traits

Get the traits in a collection.

Refresh nft metadata

Refresh metadata for a single NFT.

FAQ

Frequently asked questions

With a standalone Open sea MCP server, the agents and LLMs can only access a fixed set of Open sea tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Open sea and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. Claude Code fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Open sea tools.

Yes, absolutely. You can configure which Open sea scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Open sea data and credentials are handled as safely as possible.

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