## 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.
## 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.SIGN UP
## 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.LOG IN
Connect Claude Code to Postmark MCP. Send a password reset email to user, get delivery status for last 10 emails, and more using natural language, with authentication handled for you.
Postmark is an email delivery service for sending transactional emails with reliable deliverability. It delivers detailed analytics and fast, secure email delivery for developers.
Manage your Postmark 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. Add the Composio MCP to Claude
2. Start Claude Code
claude3. Open your MCP list
/mcp4. Select Composio and click on Authenticate
5. This will redirect you to the Composio OAuth page. Complete the flow by authorizing Composio and you're all set.
The Postmark MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Postmark account. It provides structured and secure access to transactional email sending and analytics, so your agent can perform actions like delivering transactional emails, monitoring delivery status, managing templates, and analyzing engagement metrics on your behalf.
Composio SDK is the underlying technology that powers these integrations. It provides a universal gateway with full programmatic control. You can programmatically generate an MCP URL with the app you need (here Postmark) for even more tool search precision. It's secure and reliable.
The Composio SDK follows a three-phase workflow:
# 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.cmdTo install Claude Code, use one of the following methods based on your operating system:
cd your-project-folder
claudeOpen a terminal, go to your project folder, and start Claude Code:
COMPOSIO_API_KEY=your_composio_api_key_here
USER_ID=your_user_id_hereCreate 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)npm install @composio/core dotenvInstall the Composio TypeScript library to create MCP sessions.
@composio/core provides the core Composio functionalitydotenv loads environment variables from your .env fileimport '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: ['postmark'],
});
const composioMcpUrl = composioSession?.mcp.url;
console.log(`MCP URL: ${composioMcpUrl}`);
console.log(`\nUse this command to add to Claude Code:`);
console.log(`claude mcp add --transport http postmark-composio "${composioMcpUrl}" --headers "X-API-Key:${COMPOSIO_API_KEY}"`);Create a script to generate a Composio MCP URL for Postmark. This URL will be used to connect Claude Code to Postmark.
What's happening
create() to create a Tool Router session for Postmarkmcp.url is the MCP server URL that Claude Code will usenode --loader ts-node/esm generate_mcp_url.ts
# or if using tsx
tsx generate_mcp_url.tsRun your TypeScript script to generate the MCP URL.
claude mcp add command from the outputclaude mcp add --transport http postmark-composio "YOUR_MCP_URL_HERE" --headers "X-API-Key:YOUR_COMPOSIO_API_KEY"
# Then restart Claude Code
exit
claudeIn 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 serverpostmark-composio) is how you'll reference it--headers includes your Composio API key for authenticationAfter running the command, close the current Claude Code session and start a new one for the changes to take effect.
claude mcp listCheck that your Postmark MCP server is properly configured.
postmark-composio entry in the listIf everything is wired up, you should see your postmark-composio entry listed:
The first time you try to use Postmark tools, you'll be prompted to authenticate.
Once authenticated, you can ask Claude Code to perform Postmark operations in natural language. For example:
Here's the complete code to get you started with Postmark 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: ['postmark'],
});
const composioMcpUrl = composioSession?.mcp.url;
console.log(`MCP URL: ${composioMcpUrl}`);
console.log(`\nUse this command to add to Claude Code:`);
console.log(`claude mcp add --transport http postmark-composio "${composioMcpUrl}" --headers "X-API-Key:${COMPOSIO_API_KEY}"`);You've successfully integrated Postmark with Claude Code using Composio's MCP server. Now you can interact with Postmark directly from your terminal using natural language commands.
Key features of this setup:
Next steps:
You can extend this by adding more toolkits, implementing custom workflows, or building automation scripts that leverage Claude Code's capabilities.
Every Postmark action and event your agent gets out of the box.
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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.
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Managed auth, hosted MCP servers, and every Postmark 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