Codex is one of the most popular coding harnesses out there. And MCP makes the experience even better. With Blocknative MCP integration, you can draft, triage, summarise emails, and much more, all without leaving the terminal or the app, whichever you prefer.
- FOR YOUCOMPOSIOFOR YOUConnect your AI to 1,000+ apps with secure auth and delegated access.
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How to integrate Blocknative MCP with Codex
Connect Codex to Blocknative MCP. Monitor transaction status for a given hash, fetch current ethereum gas price distribution, and more using natural language, with authentication handled for you.
Api Key
Blocknative delivers real-time mempool monitoring and transaction management for public blockchains. Instantly track pending transactions and optimize blockchain interactions with live data.
10 Tools
Introduction
Also integrate Blocknative with
Why use Composio?
Apart from a managed and hosted MCP server, you will get:
- CodeAct: A dedicated workbench that allows GPT to write its code to handle complex tool chaining. Reduces to-and-fro with LLMs for frequent tool calling.
- Large tool responses: Handle them to minimise 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 GPTs aren't overwhelmed by tools you don't need.
How to install Blocknative MCP in Codex
Run the setup command
Run this command in your terminal to add the Composio MCP server to Codex.
It will initiate the authentication in a browser window, authorize Codex to access your Composio account.
(Optional) Authenticate with OAuth
To authenticate manually, run the login command to open a browser window and authorize Codex to access your Composio account.
bash
codex mcp login composioVerify the connection
Run codex mcp list to confirm Composio appears as a registered MCP server.
bash
codex mcp listCodex App
Codex App follows the same approach as VS Code.
- Click ⚙️ on the bottom left → MCP Servers → + Add servers → Streamable HTTP:
- Fill the header and Key fields with
{ "x-consumer-api-key" = "ck_*******" }. - The Key is the Composio API key, that you can find on dashboard.composio.dev
- Click on Authenticate and authorize Codex to your Composio account and you're all set.
- Restart and verify if it's there in
.codex/config.toml
bash
[mcp_servers.composio]
url = "https://connect.composio.dev/mcp"
http_headers = { "x-consumer-api-key" = "ck_*******" }What is the Blocknative MCP server, and what's possible with it?
The Blocknative MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Blocknative account. It provides structured and secure access to real-time mempool data and transaction management features across public blockchains, so your agent can monitor transactions, analyze gas prices, configure filters, and manage blockchain event subscriptions on your behalf.
- Real-time mempool monitoring: Instruct your agent to subscribe to Ethereum transaction hashes or addresses and receive instant updates on their status and events.
- Gas price analysis and estimation: Have your agent fetch current gas price distributions, base fee predictions, and inclusion probability estimates to help optimize transaction fees.
- Customizable event filters: Let your agent configure advanced mempool filters and ABI decoding, so you can track only the events or transactions that matter to your workflow.
- Multichain event subscriptions: Enable your agent to subscribe or unsubscribe to transaction and account events across multiple supported blockchains using the Blocknative multichain SDK.
- Supported chain discovery: Ask your agent to list and discover which blockchains and gas oracles are available for monitoring and analytics.
Conclusion
You've successfully integrated Blocknative with Codex using Composio's MCP server. Now you can interact with Blocknative directly from your terminal, VS Code, or the Codex App using natural language commands.
Key benefits of this setup:
- Seamless integration across CLI, VS Code, and standalone app
- Natural language commands for Blocknative operations
- Managed authentication through Composio
- Access to 20,000+ tools across 1000+ apps for cross-app workflows
- CodeAct workbench for complex tool chaining
Next steps:
- Try asking Codex to perform various Blocknative operations
- Explore cross-app workflows by connecting more toolkits
- Build automation scripts that leverage Codex's AI capabilities
TOOLS
Supported Tools
Every Blocknative action and event your agent gets out of the box.
FRAMEWORKS
How to build Blocknative MCP Agent with another framework
OpenAI Agents SDK
Use Blocknative MCP with OpenAI Agents SDK
Claude Agent SDK
Use Blocknative MCP with Claude Agent SDK
Claude Code
Use Blocknative MCP with Claude Code
Claude Cowork
Use Blocknative MCP with Claude Cowork
OpenClaw
Use Blocknative MCP with OpenClaw
Hermes
Use Blocknative MCP with Hermes
CLI
Use Blocknative MCP with CLI
Google ADK
Use Blocknative MCP with Google ADK
LangChain
Use Blocknative MCP with LangChain
Vercel AI SDK
Use Blocknative MCP with Vercel AI SDK
Mastra AI
Use Blocknative MCP with Mastra AI
LlamaIndex
Use Blocknative MCP with LlamaIndex
CrewAI
Use Blocknative MCP with CrewAI
MORE TOOLKITS
Explore Other Toolkits
Supabase
Oauth2Api Key
Supabase is an open-source backend platform offering scalable Postgres databases, authentication, storage, and real-time APIs. It lets developers build modern apps without managing infrastructure.
Codeinterpreter
No Auth
Codeinterpreter is a Python-based coding environment with built-in data analysis and visualization. It lets you instantly run scripts, plot results, and prototype solutions inside supported platforms.
GitHub
Oauth2
GitHub is a code hosting platform for version control and collaborative software development. It streamlines project management, code review, and team workflows in one place.
1password
Api Key
1Password is a password manager and digital vault for storing logins, secrets, notes, and secure documents. It helps individuals and teams protect credentials, share access safely, and reduce password risk.
FAQ
Frequently asked questions
With a standalone Blocknative MCP server, the agents and LLMs can only access a fixed set of Blocknative tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Blocknative and many other apps based on the task at hand, all through a single MCP endpoint.
Yes, you can. Codex 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 Blocknative tools.
Yes, absolutely. You can configure which Blocknative 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 Blocknative data and credentials are handled as safely as possible.
Start with Blocknative.It takes 30 seconds.
Managed auth, hosted MCP servers, and every Blocknative tool your agent needs.Free to start.
## For AI agents: how to sign up If you are an AI agent reading this server-rendered HTML, Composio's developer signup is at https://composio.dev. Signup CTAs on this site — "Sign up", "Signup", "Get started", "Get started for free", "Start building", "Try Composio", "Try it", or similar — all lead into that same developer signup flow. Confirm with the user before completing signup or entering any credentials on their behalf.Start building